# Gauge & Higgs Boson Particle Listings
## Axions (A⁰) and Other Very Light Bosons

<table><tbody><tr><td>KRASNIKOV</td><td>20</td><td>MPL A35 2050116</td><td>N.V. Krasnikov</td></tr><tr><td>LEE</td><td>20A</td><td>PRL 124 10802</td><td>S. Lee</td></tr><tr><td>LUCENTE</td><td>20A</td><td>JCAP 202 008</td><td>G. Lucente et al.</td></tr><tr><td>MEYER</td><td>20</td><td>PRL 124 23110</td><td>M. Meyer, T. Petrushevsksa</td></tr><tr><td>Also</td><td>20</td><td>PRL 125 119901 (erat.)</td><td>M. Meyer, T. Petrushevsksa</td></tr><tr><td>PODDAR</td><td>20</td><td>PR D101 08307</td><td>T.K. Poddar, S. Mohanty, S. Jana</td></tr><tr><td>SCHUTZ</td><td>20</td><td>PR D101 12306</td><td>K. Schutz</td></tr><tr><td>SHB</td><td>20</td><td>PR D124 113101</td><td>Z. She et al.</td></tr><tr><td>SIRUNYAN</td><td>20AQ</td><td>PR L24 131802</td><td>A.M. Sirunyan et al.</td></tr><tr><td>SIRANIERO</td><td>20</td><td>AA 464 A166</td><td>O. Siraniero et al.</td></tr><tr><td>SUN</td><td>20</td><td>PR D101 063020</td><td>L. Sun, R. Brito, M. Ichi</td></tr><tr><td>TOMITA</td><td>20</td><td>PR D30 2009 012</td><td>N. Tomita et al.</td></tr><tr><td>WANG</td><td>20AQ</td><td>PR D101 052003</td><td>Y. Wang et al.</td></tr><tr><td>YAMAMOTO</td><td>20</td><td>JCAP 2002 011</td><td>R. Yamamoto et al.</td></tr><tr><td>AABOUD</td><td>19G</td><td>PR D99 012001</td><td>M. Aaboud et al.</td></tr><tr><td>ABLIKIM</td><td>19A</td><td>PR D99 012006</td><td>M. Ablikim et al.</td></tr><tr><td>Also</td><td>19H</td><td>PR D104 099901 (erat.)</td><td>M. Ablikim et al.</td></tr><tr><td>ABDELGERGER</td><td>19B</td><td>PR L24 169001</td><td>M. Ablikim et al.</td></tr><tr><td>ADHIKARI</td><td>19B</td><td>ASP 114 101</td><td>P. Adhikari et al.</td></tr><tr><td>AGUILAR-AR...</td><td>19A</td><td>PR L23 181802</td><td>A. Aguilar-Arevalo et al.</td></tr><tr><td>AHN</td><td>19</td><td>PR L22 021802</td><td>J.K. Ahn et al.</td></tr><tr><td>ALONI</td><td>19</td><td>PR D101 101101</td><td>D. Alesini et al.</td></tr><tr><td>ALONI</td><td>19</td><td>PR L23 071801</td><td>Alonii et al.</td></tr><tr><td>APRILE</td><td>19</td><td>PR L23 071301</td><td>E. Aprile et al.</td></tr><tr><td>APRILE</td><td>19D</td><td>PR L23 251801</td><td>E. Aprile et al.</td></tr><tr><td>ARNOLD</td><td>19</td><td>EPJ B79 440</td><td>R. Arnold et al.</td></tr><tr><td>BANERJEE</td><td>19</td><td>PR L23 121801</td><td>D. Banerjee et al.</td></tr><tr><td>BHOONAN</td><td>19</td><td>PR D100 023001</td><td>A. Bhoonan et al.</td></tr><tr><td>BRUN</td><td>19</td><td>PR L22 201801</td><td>P. Brun, L. Chevalier, C. Flouzat</td></tr><tr><td>CAPUTO</td><td>19</td><td>PR D100 063515</td><td>A. Caputo et al.</td></tr><tr><td>CORTINA-GIL</td><td>19</td><td>JHEP 1905 182</td><td>E. Cortina Gil et al.</td></tr><tr><td>DANILOV</td><td>19</td><td>PR L22 041801</td><td>M. Danilov, S. Demidov, D. Gorbunov</td></tr><tr><td>DAVOUDIASI</td><td>19</td><td>PR L22 021102</td><td>(NBL)</td></tr><tr><td>DESSERT</td><td>19</td><td>PR L23 061104</td><td>C. Dessert, A.J. Long, B.R. Safdi (MICH)</td></tr><tr><td>FEDDERKE</td><td>19</td><td>PR D100 015040</td><td>M.A. Fedderke, P.W. Graham, S. Rajendran (STAN+)</td></tr><tr><td>FUJITA</td><td>19</td><td>PR L22 191101</td><td>T. Fujita, R. Tazaki, K. Toma (KYOT, GEVA, TOHO)</td></tr><tr><td>HOCHBERG</td><td>19</td><td>PR L23 15802</td><td>Y. Hochberg et al.</td></tr><tr><td>HANSEN</td><td>19</td><td>PR L23 059</td><td>M.M. Ivanov et al.</td></tr><tr><td>KOPYLOV</td><td>19</td><td>JCAP 1907 008</td><td>A. Kopylov, I. Orekhov, V. Petukhov (INRM)</td></tr><tr><td>KOVETZ</td><td>19</td><td>PR D99 123511</td><td>E.D. Kovetz, I. Cholis, D.E. Kaplan</td></tr><tr><td>LEINSON</td><td>19</td><td>PR L91 0311</td><td>L.J. Leinson</td></tr><tr><td>LIANG</td><td>19</td><td>JCAP 1906 042</td><td>S.F. Liang et al.</td></tr><tr><td>LLOYD</td><td>19</td><td>PR D100 063005</td><td>S.J. Lloyd et al.</td></tr><tr><td>MAHSH</td><td>19</td><td>PR L23 051103</td><td>D.J.E. Marsh, J.C. Niemeyer</td></tr><tr><td>NGUYEN</td><td>19</td><td>JCAP 1910 014</td><td>L.H. Nguyen, A. Lobanov, D. Horns (WISPDMX Coll.)</td></tr><tr><td>QUELLET</td><td>19A</td><td>PR L22 12802</td><td>J.L. Quelet et al. (ABRACADABRA Coll.)</td></tr><tr><td>PALOMBA</td><td>19</td><td>PR L23 171101</td><td>C. Palomba et al.</td></tr><tr><td>SIRUNYAN</td><td>19BQ</td><td>PR B796 131</td><td>A.M. Sirunyan et al.</td></tr><tr><td>SMORRA</td><td>19</td><td>NAT 575 310</td><td>C. Smorra et al.</td></tr><tr><td>TERRANO</td><td>19</td><td>PR L22 231301</td><td>W. Terrano et al.</td></tr><tr><td>WU</td><td>19</td><td>PR L22 191302</td><td>T. Wu et al.</td></tr><tr><td>WU</td><td>19C</td><td>PR L23 169002</td><td>T. Wu et al.</td></tr><tr><td>ABE</td><td>18F</td><td>PR B787 153</td><td>K. Abe et al.</td></tr><tr><td>ADRIAN</td><td>18</td><td>PR D98 091101</td><td>P.H. Adrian et al.</td></tr><tr><td>AKHMATOV</td><td>18</td><td>PPN 49 599</td><td>Z.A. Akmatov et al.</td></tr><tr><td>ANASTASI</td><td>18B</td><td>PR B784 336</td><td>A. Anastasi et al.</td></tr><tr><td>ARMENGAUD</td><td>18</td><td>PR D98 082004</td><td>E. Armengaud et al.</td></tr><tr><td>ARNOLD</td><td>18</td><td>EPJ C78 821</td><td>R. Arnold et al.</td></tr><tr><td>BANERJEE</td><td>18A</td><td>PR L20 231802</td><td>D. Banerjee et al.</td></tr><tr><td>BANERJEE</td><td>18A</td><td>PR L20 231802</td><td>D. Banerjee et al.</td></tr><tr><td>BEZNOGOV</td><td>18A</td><td>PR C98 035802</td><td>M.V. Beznogov et al.</td></tr><tr><td>BOUTAN</td><td>18</td><td>PR L21 261302</td><td>C. Boutan et al.</td></tr><tr><td>CHANG</td><td>18</td><td>PR L189 051</td><td>J.C. Chang, R. Essig, S.D. McDermott</td></tr><tr><td>CRESCINI</td><td>18</td><td>EPJ C78 703</td><td>N. Crescini et al.</td></tr><tr><td>DU</td><td>18</td><td>PR L20 151301</td><td>N. Du et al.</td></tr><tr><td>DZUBA</td><td>18</td><td>PR D98 035048</td><td>V.A. Dzuba et al.</td></tr><tr><td>FICEK</td><td>18</td><td>JHEP 120 183002</td><td>F. Fick et al.</td></tr><tr><td>FORTIN</td><td>18</td><td>JHEP 1806 048</td><td>J.-F. Fortin, K. Sinha (LAVL, OKLA)</td></tr><tr><td>GAVRILYUK</td><td>18</td><td>JETPL 107 589</td><td>Yu.M. Gavriluky et al.</td></tr><tr><td>HAMAGUCHI</td><td>18</td><td>PR D98 103015</td><td>K. Hamaguchi et al.</td></tr><tr><td>JAECKEL</td><td>18</td><td>PR D98 055032</td><td>J. Jaeckel, P. C. Maita, J. Redondo</td></tr><tr><td>KNIRCK</td><td>18</td><td>S. Knirck et al.</td><td>S. Knirck et al.</td></tr><tr><td>PORAYKO</td><td>18</td><td>JCAP 181 031</td><td>Y.N. Poyko et al. (PPTA Coll.)</td></tr><tr><td>STADNIG</td><td>18</td><td>PR L20 013202</td><td>Y.V. Stadnik, V.A. Dzuba, V.V. Flambaum</td></tr><tr><td>YAMAJI</td><td>18</td><td>PR B782 523</td><td>T. Yamaji et al.</td></tr><tr><td>ZHANG</td><td>18</td><td>PR D97 063009</td><td>C. Zhang et al.</td></tr><tr><td>ZHONG</td><td>18</td><td>PR D97 092001</td><td>L. Zhong et al.</td></tr><tr><td>AAIJ</td><td>17A</td><td>PR 1701 011</td><td>J. Aaij et al.</td></tr><tr><td>ABEL</td><td>17</td><td>PR X7 041034</td><td>C. Abel et al.</td></tr><tr><td>ABGRALL</td><td>17</td><td>PR L18 168101</td><td>N. Abgrall et al.</td></tr><tr><td>ABLIKIM</td><td>17A</td><td>PR B744 336</td><td>M. Ablikim et al.</td></tr><tr><td>ADE</td><td>17</td><td>PR D96 102003</td><td>P.A.R. Ade et al.</td></tr><tr><td>AHN</td><td>17</td><td>PR D96 102003</td><td>J.K. Ahn et al.</td></tr><tr><td>AKERIB</td><td>17B</td><td>PR L18 261301</td><td>D.S. Akerib et al.</td></tr><tr><td>AKIMASSO</td><td>17B</td><td>NATP 13 584</td><td>V. Anastassopoulos et al.</td></tr><tr><td>ANGLOHER</td><td>17B</td><td>EPJ C77 299</td><td>G. Angloher et al.</td></tr><tr><td>APRILE</td><td>17B</td><td>PR D99 029904</td><td>A. Aprile et al.</td></tr><tr><td>BANERJEE</td><td>17A</td><td>PR L18 118002</td><td>D. Banerjee et al.</td></tr><tr><td>BATLEY</td><td>17</td><td>PL B769 67</td><td>J.R. Batley et al.</td></tr><tr><td>BRANCA</td><td>17</td><td>PL B77 013202</td><td>A. Branca et al.</td></tr><tr><td>BRUBAKER</td><td>17</td><td>PR L18 061302</td><td>B.M. Brubaker et al.</td></tr><tr><td>CHANG</td><td>17</td><td>JHEP 1701 017</td><td>J.H. Chang, R. Essig, S.D. McDermott (STON)</td></tr><tr><td>CHOI</td><td>17</td><td>PR D96 061102</td><td>J. Choi et al. (CAPP-ACTION Coll.)</td></tr><tr><td>CRESCINI</td><td>17</td><td>PL B773 677</td><td>N. Crescini et al.</td></tr><tr><td>DAIDO</td><td>17</td><td>PL B772 127</td><td>R. Daido, F. Takahashi</td></tr><tr><td>DOLAN</td><td>17</td><td>JHEP 1712 094</td><td>M.J. Dolan et al.</td></tr><tr><td>DUBININA</td><td>17</td><td>PR L210 1309 (erat.)</td><td>PAN 80 461</td></tr><tr><td>FICEK</td><td>17A</td><td>PR A95 032505</td><td>F. Fick et al.</td></tr><tr><td>FU</td><td>17A</td><td>PR L19 18106</td><td>C. Fu et al.</td></tr><tr><td>INADA</td><td>17</td><td>PR L18 071803</td><td>T. Inada et al.</td></tr><tr><td>KLIMCHITSK...</td><td>17A</td><td>PR D95 123013</td><td>G.L. Klimchitskaya, V.M. Mostepanenko</td></tr><tr><td>KOHRI</td><td>17</td><td>PR D96 051701</td><td>K. Kohri, H. Kodama (KEK, KYOT)</td></tr><tr><td>LEES</td><td>17E</td><td>PR L19 113804</td><td>J.P. Lees et al.</td></tr><tr><td>LIU</td><td>17E</td><td>PL B766 117</td><td>X.-H. Liu</td></tr><tr><td>LIU</td><td>17A</td><td>PR D95 052006</td><td>S.K. Liu et al.</td></tr><tr><td>LUO</td><td>17A</td><td>PR D95 055028</td><td>M.C.D. Marsh et al.</td></tr><tr><td>MARSH</td><td>17</td><td>PR L712 036</td><td>B.T. McAllister et al.</td></tr><tr><td>MCALLISTER</td><td>17</td><td>PDU 18 67</td><td>A. McAllister et al.</td></tr><tr><td>TIWARI</td><td>17</td><td>PR D95 023005</td><td>P. Tiwari (Technion)</td></tr><tr><td>AAD</td><td>16AG</td><td>JHEP 1602 062</td><td>G. Aad et al.</td></tr><tr><td>ABLIKIM</td><td>16E</td><td>PR D95 052005</td><td>M. Ablikim et al.</td></tr><tr><td>AJELLOSI</td><td>16</td><td>PR L16 116101</td><td>M. Ajello et al.</td></tr><tr><td>ANASTASI</td><td>16</td><td>PR L24 169001 (erat.)</td><td>A. Anastasi et al.</td></tr><tr><td>BATTICH</td><td>16</td><td>PR B740 062</td><td>T. Battich et al.</td></tr><tr><td>BERENJI</td><td>16</td><td>PR D93 045019</td><td>B. Berenji et al.</td></tr><tr><td>CORSICO</td><td>16</td><td>JCAP 1607 036</td><td>A.H. Corsico et al.</td></tr><tr><td>DELLA-VALLE</td><td>16</td><td>EPJ C76 24</td><td>F. Della Valle et al.</td></tr><tr><td>HOSKINS</td><td>16</td><td>PR D97 052001</td><td>J. Hoskins et al.</td></tr><tr><td>JAECKEL</td><td>16</td><td>PL B757 356</td><td>J. Jaeckel, M. Spannowsky</td></tr><tr><td>KHACHATRY...</td><td>16</td><td>PL B752 146</td><td>V. Khachatryan et al.</td></tr></tbody></table>

<table><tbody><tr><td>KRASNAHO...</td><td>16</td><td>PR L16 042501</td><td>A.J. Krasznahorkay et al. (HINN, ANIK+)</td></tr><tr><td>LEEFER</td><td>16</td><td>PR L17 271001</td><td>N. Leefer et al. (MAINZ, BONN, LBL, UCB+)</td></tr><tr><td>WON</td><td>16</td><td>PR D94 092060</td><td>E. Won et al. (BELLE Coll.)</td></tr><tr><td>YOON</td><td>16</td><td>EPJHEP 1606 011</td><td>Y.S. Yoon et al. (KIMS Coll.)</td></tr><tr><td>AAD</td><td>15CD</td><td>PR D92 092001</td><td>G. Aad et al. (ATLAS Coll.)</td></tr><tr><td>AAIJ</td><td>15AZ</td><td>PR L15 161802</td><td>A. Adare et al. (LHCb Coll.)</td></tr><tr><td>ADARE</td><td>15</td><td>PR C91 031901</td><td>A. Adare et al. (PHENIX Coll.)</td></tr><tr><td>AFACH</td><td>15</td><td>PR B745 58</td><td>S. Afach et al. (ETH, PSI, CAEN+,)</td></tr><tr><td>AGOSTINI</td><td>15A</td><td>EPJ C75 416</td><td>M. Agostini et al. (GERDA Coll.)</td></tr><tr><td>AN</td><td>15A</td><td>PL B747 331</td><td>H. An et al. (CIT, VICT, VIAN)</td></tr><tr><td>ANASTASI</td><td>15</td><td>PL B747 365</td><td>A. Anastasi et al. (KLOE-2 Coll.)</td></tr><tr><td>ANASTASI</td><td>15</td><td>PL B750 633</td><td>A. Anastasi et al. (KLOE-2 Coll.)</td></tr><tr><td>ANASTASSO...</td><td>15</td><td>PL B749 172</td><td>V. Anastassopoulos et al. (CAST Coll.)</td></tr><tr><td>ARIK</td><td>15</td><td>PR D92 021101</td><td>M. Arik et al. (CAST Coll.)</td></tr><tr><td>ARNOLD</td><td>15</td><td>PR D92 072011</td><td>R. Arnold et al. (NEMO-3 Coll.)</td></tr><tr><td>BALLOU</td><td>15</td><td>PR D92 092002</td><td>R. Ballou et al. (OSQAR Coll.)</td></tr><tr><td>BATLEY</td><td>15</td><td>PL B746 178</td><td>J.R. Batley et al. (NA48/2 Coll.)</td></tr><tr><td>BATES</td><td>15</td><td>PL D92 052020</td><td>R. Bayes et al. (TWIST Coll.)</td></tr><tr><td>BRAX</td><td>15</td><td>PR D92 083501</td><td>P. Brax, P. Brun, D. Wouters (SACL, SACL5)</td></tr><tr><td>GAVRILYUK</td><td>15</td><td>JETPL 101 664</td><td>Yu.M. Gavriluky et al.</td></tr><tr><td>HASEBE</td><td>15</td><td>Transated from ZETFIP 101 739.</td><td>T. Hasebe et al.</td></tr><tr><td>JAEGLE</td><td>15</td><td>PR L24 11801</td><td>I. Jaegle et al.</td></tr><tr><td>KAZANAS</td><td>15</td><td>NP B890 17</td><td>D. Kazanas et al.</td></tr><tr><td>KLIMCHITSK...</td><td>15</td><td>EPJ C75 164</td><td>G.L. Klimchitskaya, V.M. Mostepanenko</td></tr><tr><td>MILLEA</td><td>15</td><td>PR D92 020310</td><td>M. Milke, L. Knox, B. Fields (UCD, ILL)</td></tr><tr><td>STADNIK</td><td>15</td><td>EPJ C75 110</td><td>Y.V. Stadnik, V.V. Flambaum (SYDN)</td></tr><tr><td>SUZUKI</td><td>15</td><td>JCAP 1509 042</td><td>J. Suzuki et al.</td></tr><tr><td>TERRANO</td><td>15</td><td>PR L15 201801</td><td>W.A. Terrano et al.</td></tr><tr><td>VANTILBURG</td><td>15</td><td>PR L15 011802</td><td>K. Van Tilburg et al.</td></tr><tr><td>VINYOLES</td><td>15</td><td>JP CAP 1510 015</td><td>N. Vinyoles et al.</td></tr><tr><td>ABE</td><td>14F</td><td>PR L11 121301</td><td>K. Abe et al.</td></tr><tr><td>AGAKISHI...</td><td>14</td><td>PL B745 265</td><td>G. Agakishiy et al.</td></tr><tr><td>ALBERT</td><td>14A</td><td>PR D90 092004</td><td>J.B. Albert et al. (EXO-200 Coll.)</td></tr><tr><td>APRILE</td><td>14B</td><td>PR D90 062009</td><td>E. Aprile et al. (XENON100 Coll.)</td></tr><tr><td>ARIK</td><td>14</td><td>PR L11 091302</td><td>M. Arik et al. (CAST Coll.)</td></tr><tr><td>AYALA</td><td>14</td><td>PR L11 191302</td><td>A. Ayala et al.</td></tr><tr><td>BABUSCI</td><td>14</td><td>PL B736 459</td><td>D. Babusci et al.</td></tr><tr><td>BATELL</td><td>14</td><td>PL B749 17802</td><td>B. Batte, R. V. Osg, Z. Surujon (EFL, STON)</td></tr><tr><td>BEZERRA</td><td>14A</td><td>PR D89 035010</td><td>V.B. Bezerra et al.</td></tr><tr><td>BEZERRA</td><td>14A</td><td>EPJ C74 2859</td><td>V.B. Bezerra et al.</td></tr><tr><td>BEZERRA</td><td>14B</td><td>PR D90 055013</td><td>V.B. Bezerra et al.</td></tr><tr><td>BEZERRA</td><td>14C</td><td>PR D89 075002</td><td>V.B. Bezerra et al.</td></tr><tr><td>BLUEMILEN</td><td>14</td><td>PL B731 320</td><td>J. Bluemlein, J. Brunner (CPPM, DESY)</td></tr><tr><td>BLUM</td><td>14</td><td>PL B737 30</td><td>K. Blum et al. (IAS, PRIN)</td></tr><tr><td>DELLA-VALLE</td><td>14</td><td>PR D90 092003</td><td>F. Della Valle et al.</td></tr><tr><td>DERBIN</td><td>14</td><td>EPJ C44 3035</td><td>A.V. Derbin et al. (PVLAS Coll.)</td></tr><tr><td>EJLI</td><td>14</td><td>PR D90 123527</td><td>D. Ejli</td></tr><tr><td>FRADETTE</td><td>14</td><td>PR D90 035022</td><td>A. Fradette et al.</td></tr><tr><td>LEES</td><td>14</td><td>PR L11 23012</td><td>J.P. Lees et al. (BABAR Coll.)</td></tr><tr><td>LEINSON</td><td>14</td><td>JP CAP 1408 031</td><td>L. Leinson</td></tr><tr><td>MERKEL</td><td>14</td><td>JP CAP 112 21802</td><td>H. Merkel et al. (A1 at MAMI)</td></tr><tr><td>MILLER-BER...</td><td>14</td><td>JP CAP 1410 069</td><td>M.M. Miller Bertolami et al.</td></tr><tr><td>PUGNAT</td><td>14</td><td>JP C74 3027</td><td>P. Pugnat et al.</td></tr><tr><td>REESMAN</td><td>14</td><td>JP CAP 1408 021</td><td>R. Reesman et al. (OSU)</td></tr><tr><td>ABE</td><td>13D</td><td>PL B724 46</td><td>K. Abe et al. (XMASS Coll.)</td></tr><tr><td>ABRAMOWSKI 13A</td><td>13</td><td>PR D88 102003</td><td>A. Abramowski et al. (H.E.S.S. Coll.)</td></tr><tr><td>ADLARSON</td><td>13</td><td>PL B726 187</td><td>P. Adlarson et al. (WASA-at-COSY Coll.)</td></tr><tr><td>AESANDRIA 13</td><td>13</td><td>JP CAP 1305 007</td><td>F. Alessandria et al.</td></tr><tr><td>AN</td><td>13B</td><td>PL B725 190</td><td>H. An, M. Pospelov, J. Pradler</td></tr><tr><td>AN</td><td>13C</td><td>JP CAP 111 041302</td><td>M. Archidaccono et al.</td></tr><tr><td>ARCHIDIACIO...</td><td>13A</td><td>JP CAP 1311 020</td><td>E. Armengaud et al. (EDELWEISS-II Coll.)</td></tr><tr><td>ARMENGAUD</td><td>13</td><td>JP CAP 1311 067</td><td>D. Babusci et al. (KLOE-2 Coll.)</td></tr><tr><td>BABUSCI</td><td>13B</td><td>JP B720 110</td><td>K. Barth et al. (CAST Coll.)</td></tr><tr><td>BARTH</td><td>13</td><td>JP CAP 1305 010</td><td>C. Beck</td></tr><tr><td>BECK</td><td>13</td><td>PR L11 231801</td><td>M. Betz et al. (CROWS Coll.)</td></tr><tr><td>BETZ</td><td>13</td><td>PR D88 075014</td><td>M. Bulatowicz et al.</td></tr><tr><td>BULATOWICZ</td><td>13</td><td>PR L11 102001</td><td>P.-H. Chu et al. (DUKE, IND, SJTU)</td></tr><tr><td>CHU</td><td>13</td><td>JP B77 744</td><td>A. V. Derbin et al. (A. V. Derbin et al. P. Brun)</td></tr><tr><td>DERBIN</td><td>13</td><td>EPJ C73 2490</td><td>M.D. Diamond, P. Schuster</td></tr><tr><td>DANDIAND</td><td>13</td><td>PR L10 221803</td><td>A. Friedland, M. Giannotti, M. Wise (INRM)</td></tr><tr><td>FRIEDLAND</td><td>13</td><td>PR L11 061101</td><td>S.N. Ginnenko</td></tr><tr><td>GNINENKO</td><td>13</td><td>PR D87 035030</td><td>HECKEL et al. (KamLAND-Zen Coll.)</td></tr><tr><td>HECKEL</td><td>13</td><td>PL B731 220</td><td>R. Horvat et al.</td></tr><tr><td>HORVAT</td><td>13</td><td>PL B721 301</td><td>T. Inada et al.</td></tr><tr><td>INADA</td><td>13</td><td>LATTANZI</td><td>K. Lattanzi et al. (HADAM-KIEV)</td></tr><tr><td>Meyer</td><td>13</td><td>PR D87 035207</td><td>M. Meyer, D. Horns, M. Raue</td></tr><tr><td>MIZUMOTO</td><td>13</td><td>JP CAP 1307 013</td><td>T. Mizumoto et al.</td></tr><tr><td>PARKER</td><td>13</td><td>PR D88 112004</td><td>S. Parker et al.</td></tr><tr><td>REDONDO</td><td>13</td><td>JP CAP 1308 010</td><td>J. Redondo, G. Raffelt</td></tr><tr><td>TULLEY</td><td>13</td><td>PR L11 100801</td><td>K. Tuley et al.</td></tr><tr><td>VIAUX</td><td>13A</td><td>PR L11 231301</td><td>N. Viaux et al.</td></tr><tr><td>WOUTERS</td><td>13A</td><td>APJ 772 44</td><td>A. Wouters, P. Brun (SACL)</td></tr><tr><td>ABLIKIM</td><td>12</td><td>PR D85 092022</td><td>A. Ablikim et al. (BESIII Coll.)</td></tr><tr><td>ARCHILLI</td><td>12</td><td>PL B706 251</td><td>F. Archilli et al. (KLOE-2 Coll.)</td></tr><tr><td>BELLI</td><td>12</td><td>PL B731 41</td><td>P. Bell et al. (LIEG)</td></tr><tr><td>BELLINI</td><td>12B</td><td>PR D85 092003</td><td>G. Bellini et al. (Borexino Coll.)</td></tr><tr><td>CADAMURRO</td><td>12</td><td>JP CAP 1202 032</td><td>Cadamuro et al. (MPIM)</td></tr><tr><td>CORSICO</td><td>12</td><td>JP CAP 1212 010</td><td>A.H. Cosico et al. (LAPL, RGSUL, WASH+)</td></tr><tr><td>DERBIN</td><td>12</td><td>JETPL 95 339</td><td>A.V. Derbin et al. (PNPI)</td></tr><tr><td>GANDO</td><td>12</td><td>PR C86 021601</td><td>A. Gando et al. (KamLAND-Zen Coll.)</td></tr><tr><td>GNINENKO</td><td>12A</td><td>PR D85 055027</td><td>S.N. Ginnenko et al.</td></tr><tr><td>GNINENKO</td><td>12B</td><td>PL B713 244</td><td>S.N. Ginnenko et al.</td></tr><tr><td>PAYEZ</td><td>12</td><td>JP CAP 1207 041</td><td>A. Payez et al. (LIEG)</td></tr><tr><td>RAFFELT</td><td>12</td><td>PR D86 015001</td><td>G. Raffelt (MPIM)</td></tr><tr><td>AALSETH</td><td>11</td><td>PR L106 131301</td><td>C.E. Aalseth et al. (CoGENT Coll.)</td></tr><tr><td>ABRAHAMY...</td><td>11</td><td>PR L107 191804</td><td>S. Abrahamyan et al. (CAST Coll.)</td></tr><tr><td>ARIK</td><td>11</td><td>PR L107 261302</td><td>M. Arik et al. (CAST Coll.)</td></tr><tr><td>ARNOLD</td><td>11</td><td>PR L107 062504</td><td>R. Arnold et al. (NEMO-3 Coll.)</td></tr><tr><td>BLUEMILEN</td><td>11</td><td>JP CAP 1102 032</td><td>J. Bluemlein, J. Brunner (DESY)</td></tr><tr><td>CADAMURRO</td><td>11</td><td>JP CAP 1102 003</td><td>D. Cadamuro et al. (MPIM, AARHUS)</td></tr><tr><td>DERBIN</td><td>11</td><td>JP 112 5946</td><td>A.V. Derbin et al. (PNPI)</td></tr><tr><td>DERBIN</td><td>11A</td><td>PR D63 023505</td><td>A.V. Derbin et al. (PNPI)</td></tr><tr><td>HOEDL</td><td>11</td><td>PR L06 041801</td><td>S.A. Heedl et al. (WASH)</td></tr><tr><td>HOSKINS</td><td>11</td><td>JP D84 121302</td><td>S. Andramionje et al. (ADMX Coll.)</td></tr><tr><td>ANDRIAMON...</td><td>10</td><td>JP CAP 1003 032</td><td>J. Andramionje et al. (NEMO-3 Coll.)</td></tr><tr><td>ARGYRIADES</td><td>10</td><td>NP A847 168</td><td>J. Argylades et al. (NEMO-3 Coll.)</td></tr><tr><td>ASZTALOS</td><td>10</td><td>PR L104 041301</td><td>S.J. Asztalos et al. (ALPS Coll.)</td></tr><tr><td>EHREH</td><td>10</td><td>PL B609 149</td><td>K. Ehret et al.</td></tr><tr><td>HANNESTAD</td><td>10</td><td>JP CAP 1008 001</td><td>S. Hannestad et al. (A.K. Petukhov et al.)</td></tr><tr><td>PETUKHOV</td><td>10</td><td>JP 105 170401</td><td>A.P. Serebrov et al. (A.P. Serebrov et al.)</td></tr><tr><td>SEREBROV</td><td>10</td><td>JETPL 91 6</td><td>Transated from ZETFIP 91 B</td></tr><tr><td>AHMED</td><td>09A</td><td>PR L13 141802</td><td>Z. Ahmed et al. (CDMS Coll.)</td></tr><tr><td>ANDRIAMON...</td><td>09</td><td>JP CAP 0912 002</td><td>A. Andramionje et al. (J. Andryiades et al.)</td></tr><tr><td>ARGYRIADES</td><td>09</td><td>JP C80 032501</td><td>E. Arik et al. (NEMO-3 Coll.)</td></tr><tr><td>ARIK</td><td>09</td><td>JP CAP 0902 008</td><td>J. Bjorken et al. (CAST Coll.)</td></tr><tr><td>BJORKEN</td><td>09</td><td>JP D80 075018</td><td>J. Bjorken et al. (GAMMEv Coll.)</td></tr><tr><td>CHOU</td><td>09</td><td>PR L02 034042</td><td>A. Chou et al. (GAMMEv Coll.)</td></tr><tr><td>DAVOUDIASI</td><td>09</td><td>PR D79 095024</td><td>H. Davoudiasl, P. Huber</td></tr></tbody></table>
Gauge & Higgs Boson Particle Listings
Axions (A⁰) and Other Very Light Bosons

<table><tbody><tr><td>DERBIN</td><td>09A</td><td>PL B678 181</td><td>A.V. Derbin et al.</td></tr><tr><td>GONDOLO</td><td>09</td><td>PR D79 107301</td><td>P. Gondolo, G. Raffelt</td></tr><tr><td>IGNATOVICH</td><td>09</td><td>EPJ C64 19</td><td>V.K. Ignatov, Y.N. Pokotilovski</td></tr><tr><td>KEKEZ</td><td>09</td><td>PL B671 345</td><td>D. Kekek et al.</td></tr><tr><td>SEREBROV</td><td>09</td><td>PL B680 423</td><td>A. Serebrov</td></tr><tr><td>AFANASEV</td><td>08</td><td>PRL 101 120401</td><td>A. Afanasev et al.</td></tr><tr><td>BELLINI</td><td>08</td><td>EPJ C54 1</td><td>G. Bellini et al.</td></tr><tr><td>CHOU</td><td>08</td><td>PRL 100 080402</td><td>A.S. Chou et al.</td></tr><tr><td>FOUCHE</td><td>08</td><td>PRL D78 032013</td><td>M. Fouche et al.</td></tr><tr><td>HANNESTAD</td><td>07</td><td>JCAP 0804 019</td><td>S. Hannestad et al.</td></tr><tr><td>INOUE</td><td>08</td><td>PL B668 93</td><td>Y. Inoue et al.</td></tr><tr><td>ZAVATTINI</td><td>08</td><td>PRL D77 032006</td><td>E. Zavattini et al.</td></tr><tr><td>ADELBERGER</td><td>07</td><td>PL 98 131104</td><td>E.G. Adelberger et al.</td></tr><tr><td>ANDRIAMON...</td><td>07</td><td>JCAP 0704 010</td><td>S. Andrianjonje et al.</td></tr><tr><td>BAESSLER</td><td>07</td><td>PRL D75 075006</td><td>S. Baessler et al.</td></tr><tr><td>CHANG</td><td>07</td><td>PRL D75 052004</td><td>H.M. Chang et al.</td></tr><tr><td>HANNESTAD</td><td>07</td><td>JCAP 0708 015</td><td>S. Hannestad et al.</td></tr><tr><td>JAIN</td><td>07</td><td>JP G34 129</td><td>P.L. Jain, G. Singh</td></tr><tr><td>LESSA</td><td>07</td><td>PRL D75 094001</td><td>A.P. Lessa, O.L.G. Peres</td></tr><tr><td>MELCHIORI</td><td>07A</td><td>PRL 041 07304</td><td>A. Melchiorri, O. Mena, A. Slosar</td></tr><tr><td>ROBILIARD</td><td>07</td><td>PRL 99 190403</td><td>C. Robilliard et al.</td></tr><tr><td>ARNOLD</td><td>06</td><td>NP A765 483</td><td>R. Arnold et al.</td></tr><tr><td>DUFFY</td><td>06</td><td>PRL D74 012006</td><td>L.D. Duffy et al.</td></tr><tr><td>HECKEL</td><td>06</td><td>PL 97 021603</td><td>B.R. Heckel et al.</td></tr><tr><td>ZAVATTINI</td><td>06</td><td>PRL 96 110406</td><td>E. Zavattini et al.</td></tr><tr><td>HANNESTAD</td><td>05A</td><td>JCAP 0507 002</td><td>S. Hannestad, A. Mirizzi, G. Raffelt</td></tr><tr><td>ZIOUTAS</td><td>05</td><td>PRL 94 121301</td><td>K. Zioutas et al.</td></tr><tr><td>ADLER</td><td>04</td><td>PRL D70 037102</td><td>S. Adler et al.</td></tr><tr><td>ANISIMOVSK...</td><td>04</td><td>NP D70 031801</td><td>V. Anisimovsky et al.</td></tr><tr><td>ARNOLD</td><td>04</td><td>JETPL 80 377</td><td>R. Arnold et al.</td></tr><tr><td></td><td></td><td>Translated from ZETF P 80 429</td><td></td></tr><tr><td>ASZTALOS</td><td>04</td><td>PRL D69 011101</td><td>S.J. Asztalos et al.</td></tr><tr><td>HOLZMANN</td><td>04</td><td>NP 1805003</td><td>C. Hoffmann et al.</td></tr><tr><td>ARNABOLDI</td><td>03</td><td>PL B557 167</td><td>R. Hoffmann et al.</td></tr><tr><td>CIVITARESE</td><td>03</td><td>NP 0279 687</td><td>A. Civitarese, J. Suhonen</td></tr><tr><td>DANEVICH</td><td>03</td><td>PL C68 035501</td><td>F.A. Danovich et al.</td></tr><tr><td>FARZAN</td><td>03</td><td>PL D67 073015</td><td>Y. Farzan</td></tr><tr><td>ADLER</td><td>02C</td><td>PL B537 211</td><td>S. Adler et al.</td></tr><tr><td>BARZERT...</td><td>02</td><td>PL B27 29</td><td>A.P. Barzert et al.</td></tr><tr><td>BERNABEI</td><td>02D</td><td>PL B546 23</td><td>R. Bernabei et al.</td></tr><tr><td>DERBIN</td><td>02</td><td>PAN 65 1302</td><td>R. Arnold et al.</td></tr><tr><td></td><td></td><td>Translated from YAF 65 135</td><td></td></tr><tr><td>FUSHIMI</td><td>02</td><td>PL B531 190</td><td>K. Fushimi et al.</td></tr><tr><td>INOUE</td><td>02</td><td>PL B536 18</td><td>Y. Inoue et al.</td></tr><tr><td>MORALES</td><td>02B</td><td>ASP 16 325</td><td>A. Morales et al.</td></tr><tr><td>ADLER</td><td>01B</td><td>PR D63 032004</td><td>S. Adler et al.</td></tr><tr><td>AMMAR</td><td>01B</td><td>PR 87 271801</td><td>R. Ammar et al.</td></tr><tr><td>ASHITKOV</td><td>01</td><td>JETPL 74 529</td><td>V.D. Ashitkov et al.</td></tr><tr><td></td><td></td><td>Translated from ZETF P 74 474</td><td></td></tr><tr><td>BERNABEI</td><td>01B</td><td>PL B515 6</td><td>R. Bernabei et al.</td></tr><tr><td>DANEVICH</td><td>00B</td><td>PL B479 371</td><td>P. Astler et al.</td></tr><tr><td>DANEVICH</td><td>00B</td><td>PL C62 045501</td><td>F.A. Danovich et al.</td></tr><tr><td>MASSO</td><td>00</td><td>PRL D61 011701</td><td>E. Masso</td></tr><tr><td>ARNOLD</td><td>00</td><td>NP A558 299</td><td>R. Arnold et al.</td></tr><tr><td>NI</td><td>99</td><td>PL 82 2439</td><td>W.-T. Ni et al.</td></tr><tr><td>SIMKOVIC</td><td>99</td><td>PL C60 55502</td><td>F. Simkovic et al.</td></tr><tr><td>ALTEGOER</td><td>99</td><td>PL B428 197</td><td>J. Altegoer et al.</td></tr><tr><td>ARNOLD</td><td>98</td><td>NP A636 209</td><td>R. Arnold et al.</td></tr><tr><td>ALONEGO</td><td>98</td><td>NP 81 5068</td><td>F. Wotka, H.V. Klapdor-Kleingrothous</td></tr><tr><td>DIAZ</td><td>98</td><td>NP B527 44</td><td>M.A. Diaz et al.</td></tr><tr><td>KIM</td><td>98</td><td>PL D58 055006</td><td>J.E. Kim</td></tr><tr><td>LUESCHER</td><td>98</td><td>PL B434 407</td><td>R. Luescher et al.</td></tr><tr><td>MORIYAMA</td><td>98</td><td>PL B434 147</td><td>S. Moriyama et al.</td></tr><tr><td>MOROI</td><td>98</td><td>PL B440 69</td><td>T. Moroi, H. Murayama</td></tr><tr><td>POSPелеV</td><td>98</td><td>PL D58 097703</td><td>M. Pospelov et al.</td></tr><tr><td>AHMAD</td><td>97</td><td>PL 78 618</td><td>I. Ahmad et al.</td></tr><tr><td>BORISOV</td><td>97</td><td>JETP 83 868</td><td>A.V. Borisov, V.Y.G. Ghishina</td></tr><tr><td>DEBERO</td><td>97C</td><td>JP G23 L85</td><td>F.W.N. de Boer et al.</td></tr><tr><td>KACHELRIESS</td><td>97</td><td>NP D56 1313</td><td>M. Kacheleiss, C. Wilke, G. Wunner</td></tr><tr><td>KI</td><td>97</td><td>PL D56 2419</td><td>W. Kieh et al.</td></tr><tr><td>KITCHING</td><td>97</td><td>PL 79 4079</td><td>P. Kitching et al.</td></tr><tr><td>LEINBERGER</td><td>97</td><td>PL B394 16</td><td>U. Leinberger et al. (ORANGE)</td></tr><tr><td>ADLER</td><td>96</td><td>PL 76 1421</td><td>S. Adler et al.</td></tr><tr><td>AMSLE</td><td>96B</td><td>ZPHY C70 219</td><td>A. Amsler et al.</td></tr><tr><td>GANZ</td><td>96</td><td>PL B1 3389</td><td>R. Gancz et al. (GSI, HEID, FRAN, JAGL+)</td></tr><tr><td>GUENTHER</td><td>96</td><td>PL D54 3641</td><td>M. Gunther et al. (MPIK, SASSO)</td></tr><tr><td>KAMEL</td><td>96</td><td>PL B368 291</td><td>S. Kamel</td></tr><tr><td>MITSUI</td><td>96</td><td>EPL 33 111</td><td>T. Mitsui et al.</td></tr><tr><td>YOUDIN</td><td>96</td><td>PL 77 2170</td><td>A.N. Youdin et al.</td></tr><tr><td>ALTMAHN</td><td>96</td><td>PL B46 221</td><td>M. Altmann et al. (TUM, LAPP, CPPM)</td></tr><tr><td>BASSOMPIE...</td><td>95</td><td>PL B355 468</td><td>G. Bassompierre et al.</td></tr><tr><td>MAENO</td><td>95</td><td>PL B351 574</td><td>T. Maeno et al.</td></tr><tr><td>RAFFELT</td><td>95</td><td>PL D51 1495</td><td>G. Raffelt, A. Weiss</td></tr><tr><td>SKALKEY</td><td>95</td><td>PL D51 6292</td><td>M. Skalkey, R.S. Conti</td></tr><tr><td>TSUNODA</td><td>95</td><td>EPL 30 273</td><td>T. Tsunoda et al.</td></tr><tr><td>APC</td><td>94</td><td>PL B295 3201</td><td>S. APC et al. (TUH)</td></tr><tr><td>ALLTHERR</td><td>94</td><td>PL 21 175</td><td>S. Alltherr, E. Petitgirdar, T. del Rio GazIELturrallo</td></tr><tr><td>AMSLE</td><td>94B</td><td>PL B333 271</td><td>C. Amsler et al.</td></tr><tr><td>ASAI</td><td>94</td><td>PL B332 90</td><td>S. Asai et al.</td></tr><tr><td>MEIERDREES</td><td>94</td><td>PR D49 4937</td><td>M.R. Drees et al.</td></tr><tr><td>NI</td><td>94</td><td>NP D71 153</td><td>W.T. Ni et al.</td></tr><tr><td>VO</td><td>94</td><td>NP C3 149</td><td>D.T. Vo et al.</td></tr><tr><td>ATIYA</td><td>93</td><td>PL 70 2521</td><td>W. ATIYA et al. (ISU, LBL, LLNL, UCD)</td></tr><tr><td>Also</td><td></td><td>PL D58 055006</td><td>M.S. ATIYA et al.</td></tr><tr><td>ATIYA</td><td>93B</td><td>PL D48 1</td><td>M.S. ATIYA et al.</td></tr><tr><td>BASSOMPIE...</td><td>93</td><td>EPL 22 239</td><td>G. Bassompierre et al.</td></tr><tr><td>BEZ</td><td>93</td><td>PL B29 2853</td><td>M. BEZ et al. (MPIK, KIAE, SASSO)</td></tr><tr><td>CAMERON</td><td>93</td><td>PL D47 3707</td><td>R.E. Cameron et al.</td></tr><tr><td>CHANG</td><td>93</td><td>PL B316 51</td><td>S. Chang, K. Choi</td></tr><tr><td>CHUI</td><td>93</td><td>PL RLI 71 3420</td><td>T.C.P. Chui, W.T. Ni</td></tr><tr><td>MINU</td><td>93</td><td>PL RLI 71 4210</td><td>M. Minnowa et al.</td></tr><tr><td>NG</td><td>93</td><td>PL B44 241</td><td>K. KICHLER</td></tr><tr><td>RITTER</td><td>93</td><td>PL RLI 70 701</td><td>R.C. Ritter et al.</td></tr><tr><td>TANAKA</td><td>93</td><td>PL D48 5412</td><td>J. Tanaka, H. Ejiri</td></tr><tr><td>ALLIGRE</td><td>92</td><td>PL RRL 68 278</td><td>C. Allegreio et al.</td></tr><tr><td>ATIYA</td><td>92</td><td>PL RRL 69 733</td><td>M.S. ATIYA et al.</td></tr><tr><td>BARABASH</td><td>92</td><td>PL B29 154</td><td>L.S. Barabash et al.</td></tr><tr><td>BERNATOW...</td><td>92</td><td>PL D9 2341</td><td>T. Bernatowicz et al.</td></tr><tr><td>BLUEMIEIN</td><td>92</td><td>IMP 383 65</td><td>J. Bluelein et al.</td></tr><tr><td>HALLIN</td><td>92</td><td>PR D45 3955</td><td>A.L. Hallin et al.</td></tr><tr><td>HENDERSON</td><td>92C</td><td>PL D59 1733</td><td>S.D. Henderson et al.</td></tr><tr><td>HICKS</td><td>92</td><td>PL B276 423</td><td>K.H. Hicks, D.E. Alburger</td></tr><tr><td>LAZARUS</td><td>92</td><td>PL B29 333</td><td>D.M. Lazarus et al.</td></tr><tr><td>MEIERDREES</td><td>92</td><td>PL D8 3845</td><td>R. Mejier Drees et al.</td></tr><tr><td>PAN</td><td>92</td><td>MPL A7 1287</td><td>S.S. Pan, W.T. Ni, S.C. Chen</td></tr><tr><td>RUOSO</td><td>92</td><td>ZPHY C56 505</td><td>M. Ruoso et al.</td></tr><tr><td>SKALKEY</td><td>92</td><td>PRL 68 456</td><td>M. Skalkey, J.J. Kolata</td></tr></tbody></table>

<table><tbody><tr><td>VENJEMA</td><td>92</td><td>PRL B68 135</td><td>B.J. Venema et al.</td></tr><tr><td>WANG</td><td>92</td><td>MPJ A7 1497</td><td>J. Wang</td></tr><tr><td>WANG</td><td>92C</td><td>PL B291 97</td><td>J. Wang</td></tr><tr><td>WU</td><td>92</td><td>PL 69 1729</td><td>X.Y. Wu et al.</td></tr><tr><td>AKOPYAN</td><td>92</td><td>PL B272 443</td><td>M.V. Akopyan et al.</td></tr><tr><td>ASAI</td><td>91</td><td>PL 66 2440</td><td>S. Asai et al.</td></tr><tr><td>BERSHADY</td><td>91</td><td>PL D6 1398</td><td>M.A. Bershady, M.T. Ressell, M.S. Turner</td></tr><tr><td>BLUEMIEIN</td><td>91</td><td>PZHY C51 341</td><td>J. Bluemlein et al. (BERL, BUDA, JINR+)</td></tr><tr><td>BOBRAKOV</td><td>91</td><td>JETPL 53 294</td><td>V.F. Bobrakov et al. (PNPI)</td></tr><tr><td></td><td></td><td>Translated from ZETF P 53 283</td><td></td></tr><tr><td>BROSS</td><td>91C</td><td>PRL 67 2942</td><td>A.D. Bross et al. (FNAL, ILL)</td></tr><tr><td>KIM</td><td>91C</td><td>PL 67 3465</td><td>J.E. Kim (SEOUL)</td></tr><tr><td>RAFFELT</td><td>91B</td><td>PRPL 198 1</td><td>G.G. Raffelt</td></tr><tr><td>RAFFELT</td><td>91B</td><td>PL 67 2605</td><td>G. Raffelt, D. Seckel (MPIM, BART)</td></tr><tr><td>RESSELL</td><td>91B</td><td>PR D44 3001</td><td>M.T. Ressell (CHIC, FNAL)</td></tr><tr><td>TRZASKA</td><td>91</td><td>PL B269 54</td><td>W.H. Trzaska et al. (TAMU)</td></tr><tr><td>TSEKLOS</td><td>91</td><td>PL B266 259</td><td>H. Tzeklos et al. (ILLG, GSI)</td></tr><tr><td>WALKER</td><td>91</td><td>APJ 376 51</td><td>T.P. Walker et al. (HSCA, OSU, CHIC+)</td></tr><tr><td>WIDMANN</td><td>91</td><td>ZPHY A340 209</td><td>E. Widmann et al. (STUT, GSI, STUTM)</td></tr><tr><td>WINELAND</td><td>91</td><td>PL 67 1735</td><td>D.J. Wineland et al. (NBSB)</td></tr><tr><td>ALBRECHT</td><td>90E</td><td>PL B246 278</td><td>H. Albrecht et al. (ARGUS Collab.)</td></tr><tr><td>ANTREASYAN</td><td>90C</td><td>PL B251 204</td><td>D. Antreasyan et al. (Crystal Ball Collab.)</td></tr><tr><td>ASAJIMA</td><td>90</td><td>PL B225 888</td><td>T. Asanuma et al. (TOKY)</td></tr><tr><td>ATIYA</td><td>90</td><td>PL 64 21</td><td>M.S. ATIYA et al. (BNL E787 Collab.)</td></tr><tr><td>ATIYA</td><td>90B</td><td>PL 65 1188</td><td>M.S. ATIYA et al. (BNL E787 Collab.)</td></tr><tr><td>BAUER</td><td>90</td><td>NIM B50 300</td><td>W. Bauer et al. (STUT, VILL, GSI)</td></tr><tr><td>BURROWS</td><td>90</td><td>PR D42 3297</td><td>A. Burrows, M.T. Ressell, M.S. Turner (ARIZ+)</td></tr><tr><td>DEBGER</td><td>90</td><td>JP G16 11</td><td>F.W.N. de Boer, J. Lehmann, J. Steyart (LOUVR)</td></tr><tr><td>ENGEL</td><td>90</td><td>PL 65 960</td><td>J. Engel, D. Seckel, A.C. Hayes (BART, LANL)</td></tr><tr><td>JINNENKOHN</td><td>90</td><td>PL B237 287</td><td>S.N. Ginnenko et al. (INRM)</td></tr><tr><td>GUO</td><td>90</td><td>PR D41 2924</td><td>R. Guo et al. (NIU, LANL, FNAL, CASE+)</td></tr><tr><td>HAGMANN</td><td>90</td><td>PR D41 1297</td><td>C. Hagmann et al. (FLOR)</td></tr><tr><td>JUDGE</td><td>90</td><td>PL 65 972</td><td>S.M. Judge et al. (ILLG, GSI)</td></tr><tr><td>RAFFELT</td><td>90D</td><td>PR D41 1324</td><td>G.G. Raffelt (MPIM)</td></tr><tr><td>RITTER</td><td>90D</td><td>PR D42 977</td><td>R.C. Ritter et al. (UVA)</td></tr><tr><td>SEMERTZIDIS</td><td>90</td><td>PL 64 2988</td><td>Y.K. Semertzidis et al. (ROCH, BNL, FNAL+)</td></tr><tr><td>T$\S$\U\T$\I\K$\A</td><td>90</td><td>PL B236 81</td><td>M. Tsuchiaki et al. (ICEPP)</td></tr><tr><td>TURNER</td><td>90</td><td>PRPL 197 67</td><td>M.S. Turner (CHIC, FNAL)</td></tr><tr><td>BARABASH</td><td>90</td><td>PL B227 273</td><td>A.S. Barabash et al. (ITEP, FNAL)</td></tr><tr><td>BINI</td><td>91</td><td>PL B221 99</td><td>M. Bini et al. (FIRZ, CERN, AARH)</td></tr><tr><td>BURROWS</td><td>89</td><td>PL D39 1020</td><td>A. Burrows, M.S. Turner, R.P. Brinkmann (ARIZ+)</td></tr><tr><td>Also</td><td></td><td>PL 60 1797</td><td>M.S. Turner (FNAL, EFI)</td></tr><tr><td>DEBERO</td><td>89B</td><td>PL D62 2639</td><td>F.W.N. de Boer, R. van Dantzig (ANIK)</td></tr><tr><td>ERICION</td><td>89B</td><td>PL B219 51</td><td>T.E.O. Ericson, J.F. Mathiot (CERN, IPN)</td></tr><tr><td>FAISSNER</td><td>89B</td><td>PZHY C44 557</td><td>H. Faissner et al. (AACH3, BERL, PSI)</td></tr><tr><td>FOX</td><td>89</td><td>PR C39 288</td><td>J.D. Fox et al. (FSU)</td></tr><tr><td>MAYLE</td><td>89</td><td>PL B219 515</td><td>R. Mayle et al. (LLL, CERN, MINN, FNAL+)</td></tr><tr><td>Also</td><td></td><td>PL D39 188</td><td>R. Mayle et al. (LLL, CERN, MINN, FNAL+)</td></tr><tr><td>MINOVA</td><td>89</td><td>PL 62 1091</td><td>H. Minowa et al. (ICEPP)</td></tr><tr><td>ORITO</td><td>89</td><td>PL 63 597</td><td>S. Orito et al. (ICEPP)</td></tr><tr><td>PERKINS</td><td>89</td><td>PL 62 2638</td><td>D.H. Perkins</td></tr><tr><td>T$\S$\T\O\S\T\O\R\S</td><td>89</td><td>PR D40 1397</td><td>H. Tsertos et al. (GSI, ILLG)</td></tr><tr><td>VANBIBBER</td><td>89</td><td>PL D39 2089</td><td>K. van Bibber et al. (LLL, TAMU, LBL)</td></tr><tr><td>EICHLER</td><td>89</td><td>PL D40 3153</td><td>W.U. Wuensch et al. (ROCH, BNL, FNAL)</td></tr><tr><td>BINI</td><td>89</td><td>PL 59 839</td><td>S. de Panfillis et al. (ROCH, BNL, FNAL)</td></tr><tr><td>BURROWS</td><td>89</td><td>PL D39 1020</td><td>F.T. Avignone et al. (PRIN, SCUC, ORNL+)</td></tr><tr><td>Also</td><td></td><td>PL D37 618</td><td>B. Balke et al. (LBC, LBC, COL, NWES+)</td></tr><tr><td>AVIGNONE</td><td>88</td><td>PL D37 587</td><td>J.D. Bjorken et al. (FNAL, SLAC, VPI)</td></tr><tr><td>BALKE</td><td>88</td><td>PL D38 3375</td><td>A.E. Blinov et al. (NOVO)</td></tr><tr><td>BJORKEN</td><td>88</td><td>PR D38 3375</td><td>Translated from YAF 47 889</td></tr><tr><td>BLINOV</td><td>88</td><td>SJNP 47 563</td><td>BOLTON (88)</td></tr><tr><td></td><td></td><td>PL D38 2077</td><td>R.D. Bolton et al. (LANL, STAN, CHIC+)</td></tr><tr><td>DEBERO</td><td>88</td><td>PL 56 2461</td><td>R.D. Bolton et al. (LANL, STAN, CHIC+)</td></tr><tr><td>ERICION</td><td>88</td><td>PL 57 3241</td><td>D. Grosnick et al. (CHIC, LANL, STAN+)</td></tr><tr><td>CHANDA</td><td>88</td><td>PL D37 2714</td><td>R. Chanda, J.F. Nieves, P.B. Pal (UMD, UPR+)</td></tr><tr><td>CHOI</td><td>88</td><td>PL D37 3225</td><td>K. Choi et al. (JHU)</td></tr><tr><td>CONNELL</td><td>88</td><td>PL 60 2242</td><td>S.H. Connell et al. (WITV)</td></tr><tr><td>DATAR</td><td>88</td><td>PL C37 250</td><td>V.M. Datar et al. (IPN)</td></tr><tr><td>DEBERO</td><td>88</td><td>PL D61 1274</td><td>F.W.N. de Boer, R. van Dantzig (ANIK)</td></tr><tr><td>Also</td><td></td><td>PL D62 2644 (errat.)</td><td>F.W.N. de Boer, R. van Dantzig (ANIK)</td></tr><tr><td>Also</td><td></td><td>PL D62 2638</td><td>D.H. Perkins (OXF)</td></tr><tr><td>Also</td><td></td><td>PL D62 2639</td><td>F.W.N. de Boer, R. van Dantzig (ANIK)</td></tr><tr><td>DEBERO</td><td>88C</td><td>JP G14 1131</td><td>F.W.N. de Boer et al. (LOUVR)</td></tr><tr><td>DOEHNER</td><td>88</td><td>PL D38 2722</td><td>J. Dohner et al. (HEIDP, ANL, ILLG)</td></tr><tr><td>EL-NADI</td><td>88</td><td>PL D11 1271</td><td>M. el Nadi, O.E. Badawy (CAIR)</td></tr><tr><td>EDLER</td><td>88</td><td>PL C37 731</td><td>J. Engel, P. Vogel, M.R. Zinbauer (AACH3, BERL, SIN)</td></tr><tr><td>FAISSNER</td><td>88</td><td>PZHY C37 231</td><td>H. Faissner et al. (AACH3, BERL, SIN)</td></tr><tr><td>HATSUDA</td><td>88</td><td>PL B203 469</td><td>E. Lorenz et al. (MPIM, PSI)</td></tr><tr><td>LORENZ</td><td>88</td><td>PL B214 10</td><td>R. Mayle et al. (LLL, CERN, MINN, FNAL+)</td></tr><tr><td>MAYLE</td><td>88</td><td>PL B204 188</td><td>C.E. Picciotto (TRIU, CNRC)</td></tr><tr><td>PICCIOTTO</td><td>88</td><td>PR D37 1131</td><td>G. Raffelt, D. Seckel (LBC, LLL, UCSC)</td></tr><tr><td>RAFFELT</td><td>88</td><td>PL D37 549</td><td>F.W.N. de Boer, D. Dearborn (UCB, LLL)</td></tr><tr><td>SAVAGE</td><td>88</td><td>PR D37 1134</td><td>M.J. Savage, B.W. Filippone, L.W. Mitchell (CIT)</td></tr><tr><td>T$\S$\T\O\S\T\O\R\S</td><td>88</td><td>PL B207 273</td><td>A. Tsertos et al. (GSI, ILLG)</td></tr><tr><td>T$\S$\T\O\S\T\O\R\S</td><td>88B</td><td>ZPHY A331 103</td><td>A. Tsertos et al. (GSI, ILLG)</td></tr><tr><td>VANKLINKEN</td><td>88B</td><td>PL B205 223</td><td>G. Vanklens, D. Seckel (GRON, GSI)</td></tr><tr><td>VANKLINKEN</td><td>88B</td><td>PL 60 2442</td><td>J. Jien, K. Jien et al. (GRON)</td></tr><tr><td>VONWIMMER...</td><td>88</td><td>PL 60 2443</td><td>U. von Wimmersperg (BNL)</td></tr><tr><td>VORBOVY</td><td>87</td><td>PL B208 146</td><td>P.V. Vorobely, Y.I. Gitars (NOVO)</td></tr><tr><td>DRUZHININ</td><td>87</td><td>ZPHY C37 1</td><td>V.P. Vruzhinin et al. (NOVO)</td></tr><tr><td>FRIDEN</td><td>87</td><td>PL D51 2201</td><td>T. Goldman et al. (NOVO)</td></tr><tr><td>GOLDMAN</td><td>87</td><td>PL D38 1543</td><td>J.A. Friedman, S. Dimopoulos, M.S. Turner (LNL, CHIC, STAN+)</td></tr><tr><td>KORENCHEC...</td><td>87</td><td>SJNP 46 192</td><td>S.M. Korenchenko et al. (JINR)</td></tr><tr><td>MAIER</td><td>87</td><td>ZPHY A326 527</td><td>K. Maier et al. (STUT, GSI)</td></tr><tr><td>MILLS</td><td>87</td><td>PL B1 707</td><td>A. Mills, D. Levy (BELL)</td></tr><tr><td>RAFFELT</td><td>88</td><td>PL D36 2211</td><td>A.G. Raffelt, D.S.P. Dearborn (LBC, LLL, UCB)</td></tr><tr><td>RIORDAN</td><td>87</td><td>PL D59 755</td><td>E.M. Riordan et al. (ROCH, CIT+)</td></tr><tr><td>TURNER</td><td>87</td><td>PL D59 2489</td><td>M.S. Turner (FNAL, EFI)</td></tr><tr><td>VANBIBBER</td><td>87</td><td>PL D59 759</td><td>K. van Bibber et al. (LLL, CIT, MIT+)</td></tr><tr><td>VONWIMMER...</td><td>87</td><td>PL D59 266</td><td>U. von Wimmersperg et al. (WITV)</td></tr><tr><td>BADLER</td><td>86</td><td>PZHY C33 21</td><td>J. Badler et al. (NA3 Coop)</td></tr><tr><td>BROWN</td><td>86</td><td>PL RLI 2101</td><td>C.N. Brown et al. (FNAL, WASH, KYOT+)</td></tr><tr><td>BRYMAN</td><td>86</td><td>PL RLI 2787</td><td>A.D. Bryman, E.T.H. Clifford (TRIU)</td></tr><tr><td>DAVIER</td><td>86</td><td>PL B180 295</td><td>M. Davier, J. Jeanjean, H. Nguyen Ngoc (LALO)</td></tr><tr><td>DEARBORN</td><td>86</td><td>PL D6 56 29</td><td>D.S.P. Dearborn, D.N. Schramm, G. Steigman (LLL+)</td></tr><tr><td>EICHLER</td><td>86</td><td>PL B1 101</td><td>R.A. Eicher et al. (SINDRUM)</td></tr><tr><td>HALLIN</td><td>86</td><td>PL D37 2105</td><td>A.L. Hallin et al. (PRIN)</td></tr><tr><td>JODIDIO</td><td>86</td><td>PR D34 1967</td><td>A. Jodidio et al. (LBC, NWES, TRIU)</td></tr><tr><td>Also</td><td></td><td>PR D37 237 (errat.)</td><td>A. Jodidio et al. (LBC, NWES, TRIU)</td></tr><tr><td>KETOV</td><td>86</td><td>JETF 44 146</td><td>S.N. Ketov et al. (KIAE)</td></tr><tr><td>KOCH</td><td>86</td><td>NC 96A 182</td><td>H.R. Koch, O.W.B. Schult (JULI)</td></tr><tr><td>KONAKA</td><td>86</td><td>PL A7 659</td><td>A. Konaka et al. (KYOT, KEK)</td></tr><tr><td>MAIANI</td><td>86</td><td>PL B175 359</td><td>L. Malani, R. Petronzio, E. Zavattini (CERN)</td></tr><tr><td>PECCEI</td><td>86</td><td>PL B172 435</td><td>R.D. Peccei, T.T. Wu, T. Yanagida (DESY)</td></tr><tr><td>RAFFELT</td><td>86B</td><td>PL D33 997</td><td>G.G. Raffelt (MPIM)</td></tr><tr><td>RAFFELT</td><td>86B</td><td>PL 166 402</td><td>G.G. Raffelt (MPIM)</td></tr><tr><td>SAVAGE</td><td>86B</td><td>PL RLI 57 187</td><td>M.J. Savage et al. (CIT)</td></tr><tr><td>AMALDI</td><td>85</td><td>PL 153B 444</td><td>U. Amaldi et al. (CERN)</td></tr><tr><td>ANANEV</td><td>85</td><td>SJNP 41 585</td><td>V.D. Ananev et al. (JINR)</td></tr><tr><td></td><td></td><td>Translated from YAF 41 912</td><td></td></tr></tbody></table>
# Gauge & Higgs Boson Particle Listings
## Axions (A⁰) and Other Very Light Bosons

<table><tr><td>BALTRUSAIT...</td><td>85</td><td>PRL 55 1842</td></tr><tr><td>BERGSMAN</td><td>85</td><td>PL 157B 458</td></tr><tr><td>KAPLAN</td><td>85</td><td>NP B260 215</td></tr><tr><td>IWAMOTO</td><td>84</td><td>PRL 53 1198</td></tr><tr><td>YAMAZAKI</td><td>84</td><td>PRL 52 1089</td></tr><tr><td>ABBOTT</td><td>83</td><td>PL 120B 133</td></tr><tr><td>CARBONI</td><td>83</td><td>PL 123B 349</td></tr><tr><td>CAVAIGNAC</td><td>83</td><td>PL 121B 193</td></tr><tr><td>DICUS</td><td>83</td><td>PR D28 1778</td></tr><tr><td>DINE</td><td>83</td><td>PL 120B 137</td></tr><tr><td>ELLIS</td><td>83B</td><td>NP B223 252</td></tr><tr><td>FAISSNER</td><td>83</td><td>PR D28 1198</td></tr><tr><td>FAISSNER</td><td>83B</td><td>PR D28 1707</td></tr><tr><td>FRANK</td><td>83B</td><td>PR D28 1790</td></tr><tr><td>HOFFMAN</td><td>83</td><td>PR D28 660</td></tr><tr><td>PRESKILL</td><td>83</td><td>PL 120B 127</td></tr><tr><td>SIKIVIE</td><td>83</td><td>PRL 51 1415</td></tr><tr><td>Alekseev</td><td>82</td><td>PRL 52 695 (errat.)<br/>JETP 55 591<br/>Translated from ZETF 82 1007.</td></tr><tr><td>Alekseev</td><td>82B</td><td>JETPL 36 116<br/>Translated from ZETF 36 94<br/>Y. Asano et al. (KEK, TOKY, INUS, OSAK)<br/>A. Barroso, G.C. Branco (LISB)<br/>V.M. Datar et al. (BHAB)<br/>C. Edwards et al. (Crystal Ball Collab.)<br/>W. Fetscher (ETH)<br/>M. Fukugita, S. Watamura, M. Yoshimura (KEK)<br/>M. Fukugita, S. Watamura, M. Yoshimura (KEK)<br/>P. Lehmann et al. (SACL)<br/>G. Raffelt, L. Stodolsky (MPIM)<br/>A. Zehnder, K. Gabathuler, J.L. Vuilleumier (ETH+)<br/>Y. Asano et al. (KEK, TOKY, INUS, OSAK)<br/>A. Barroso, N.C. Mukhopadhyay (SIN)<br/>H. Faissner et al. (AACH3)<br/>H. Faissner et al. (AACH3)<br/>B.R. Kim, C. Stamm (AACH3)</td></tr></table>

<table><tr><td>R.M. Baltrusaitis et al.</td><td>(Mark III Collab.)</td></tr><tr><td>F. Bergsma et al.</td><td>(CHARM Collab.)</td></tr><tr><td>D.B. Kaplan</td><td>(HARV)</td></tr><tr><td>N. Iwamoto</td><td>(UCSB, WUSL)</td></tr><tr><td>T. Yamazaki et al.</td><td>(INUS, KEK)</td></tr><tr><td>L.F. Abbott, P. Sikivie</td><td>(BRAN, FLOR)</td></tr><tr><td>G. Carboni, W. Dahme</td><td>(CERN, MUNI)</td></tr><tr><td>J.F. Cavaignac et al.</td><td>(ISNG, LAPP)</td></tr><tr><td>D.A. Dicus, V.L. Teplitz</td><td>(TEXA, UMD)</td></tr><tr><td>M. Dine, W. Fischler</td><td>(IAS, PENN)</td></tr><tr><td>J. Ellis, K.A. Olive</td><td>(CERN)</td></tr><tr><td>H. Faissner et al.</td><td>(AACH)</td></tr><tr><td>H. Faissner et al.</td><td>(AACH3)</td></tr><tr><td>J.S. Frank et al.</td><td>(LANL, YALE, LBL+)</td></tr><tr><td>C.M. Hoffman et al.</td><td>(LANL, ARZS)</td></tr><tr><td>J. Preskill, M.B. Wise, F. Wilczek</td><td>(HARV, UCSBT)</td></tr><tr><td>P. Sikivie</td><td>(FLOR)</td></tr><tr><td>P. Sikivie</td><td>(FLOR)</td></tr><tr><td>E.A. Alekseeva et al.</td><td>(KIAE)</td></tr><tr><td>G.D. Alekseev et al.</td><td>(MOSU, JINR)</td></tr></table>

<table><tr><td>VUILLEUMIER</td><td>81</td><td>PL 101B 341</td></tr><tr><td>ZEHNDER</td><td>81</td><td>PL 104B 494</td></tr><tr><td>FAISSNER</td><td>80</td><td>PL 96B 201</td></tr><tr><td>JACQUES</td><td>80</td><td>PR D21 1206</td></tr><tr><td>SOUKAS</td><td>80</td><td>PRL 44 564</td></tr><tr><td>BECHIS</td><td>79</td><td>PRL 42 1511</td></tr><tr><td>CALAPRICE</td><td>79</td><td>PR D20 2708</td></tr><tr><td>COTEUS</td><td>79</td><td>PRL 42 1438</td></tr><tr><td>DISHAW</td><td>79</td><td>PL 85B 142</td></tr><tr><td>ZHITNITSKII</td><td>79</td><td>SJNP 29 517</td></tr><tr><td>ALIBRAN</td><td>78</td><td>Translated from YAF 29 1001.</td></tr><tr><td>ASRATYAN</td><td>78B</td><td>PL 79B 497</td></tr><tr><td>BELLOTTI</td><td>78</td><td>PL 76B 223</td></tr><tr><td>BOSETTI</td><td>78B</td><td>PL 74B 143</td></tr><tr><td>DICUS</td><td>78C</td><td>PR D18 1829</td></tr><tr><td>DONNELLY</td><td>78</td><td>PR D18 1607</td></tr><tr><td>Also</td><td></td><td>PRL 37 315</td></tr><tr><td>Also</td><td></td><td>PRL 33 179</td></tr><tr><td>HANSL</td><td>78D</td><td>PL 74B 139</td></tr><tr><td>MICELMAC...</td><td>78</td><td>LNC 21 441</td></tr><tr><td>MIKAELIAN</td><td>78</td><td>PR D18 3605</td></tr><tr><td>SATO</td><td>78</td><td>PTP 60 1942</td></tr><tr><td>VYSOTSKII</td><td>78</td><td>JETPL 27 502<br/>Translated from ZETF 27 533.</td></tr><tr><td>YANG</td><td>78</td><td>PRL 41 523</td></tr><tr><td>PECCEI</td><td>77</td><td>PR D16 1791<br/>T.C. Yang (MASA)</td></tr><tr><td>Also</td><td></td><td>R.D. Peccei, H.R. Quinn (STAN, SLAC)</td></tr><tr><td>REINES</td><td>76</td><td>PRL 38 1440<br/>R.D. Peccei, H.R. Quinn (STAN, SLAC)</td></tr><tr><td>GURR</td><td>74</td><td>F. Reines, H.S. Gurr, H.W. Sobel (UCI)</td></tr><tr><td>ANAND</td><td>53</td><td>H.S. Gurr, F. Reines, H.W. Sobel (UCI)</td></tr></table>

<table><tr><td>J.L. Vuilleumier et al.</td><td>(CIT, MUNI)</td></tr><tr><td>A. Zehnder</td><td>(ETH)</td></tr><tr><td>H. Faissner et al.</td><td>(AACH3)</td></tr><tr><td>P.F. Jacques et al.</td><td>(RUTG, STEV, COLU)</td></tr><tr><td>A. Soukas et al.</td><td>(BNL, HARV, ORNL, PENN)</td></tr><tr><td>D.J. Bechis et al.</td><td>(UMD, COLU, AFRR)</td></tr><tr><td>F.P. Calaprice et al.</td><td>(PRIN)</td></tr><tr><td>P. Coteus et al.</td><td>(COLU, ILL, BNL)</td></tr><tr><td>J.P. Dishaw et al.</td><td>(SLAC, CIT)</td></tr><tr><td>A.R. Zhitnitsky, Y.I. Skovpen</td><td>(NOVO)</td></tr><tr><td>P. Alibran et al.</td><td>(Gargamelle Collab.)</td></tr><tr><td>A.E. Asratan et al.</td><td>(ITEP, SERP)</td></tr><tr><td>E. Bellotti, E. Fiorini, L. Zanotti</td><td>(MILA)</td></tr><tr><td>P.C. Bosetti et al.</td><td>(BEBC Collab.)</td></tr><tr><td>D.A. Dicus et al.</td><td>(TEXA, VPI, STAN)</td></tr><tr><td>T.W. Donnelly et al.</td><td>(STAN)</td></tr><tr><td>F. Reines, H.S. Gurr, H.W. Sobel</td><td>(UCI)</td></tr><tr><td>H.S. Gurr, F. Reines, H.W. Sobel</td><td>(UCI)</td></tr><tr><td>T. Hansl et al.</td><td>(CDHS Collab.)</td></tr><tr><td>G.V. Mitselmakher, B. Pontecorvo</td><td>(JINR)</td></tr><tr><td>K.O. Mikaetlian</td><td>(FNAL, NWES)</td></tr><tr><td>K. Sato</td><td>(KYOT)</td></tr><tr><td>M.I. Vysotsky et al.</td><td>(ASCI)</td></tr><tr><td>T.C. Yang</td><td>(STAN, SLAC)</td></tr><tr><td>R.D. Peccei, H.R. Quinn</td><td>(STAN, SLAC)</td></tr><tr><td>R.D. Peccei, H.R. Quinn</td><td>(STAN, SLAC)</td></tr><tr><td>F. Reines, H.S. Gurr, H.W. Sobel</td><td>(UCI)</td></tr><tr><td>H.S. Gurr, F. Reines, H.W. Sobel</td><td>(UCI)</td></tr><tr><td>B.M. Anand</td><td></td></tr></table>

## OTHER RELATED PAPERS

<table><tr><td>SREDNICKI</td><td>85</td><td>NP B260 689</td></tr><tr><td>BARDEEN</td><td>78</td><td>PL 74B 229</td></tr></table>

<table><tr><td>M. Srednicki</td><td>(UCSB)</td></tr><tr><td>W.A. Bardeen, S.-H.H. Tye</td><td>(FNAL)</td></tr></table>
## LEPTONS

<table><tr><td>e</td><td>1297</td></tr><tr><td>μ</td><td>1298</td></tr><tr><td>τ</td><td>1303</td></tr><tr><td>Heavy Charged Lepton Searches</td><td>1331</td></tr><tr><td>Neutrino Properties</td><td>1332</td></tr><tr><td>Number of Neutrino Types</td><td>1341</td></tr><tr><td>Double-β Decay</td><td>1343</td></tr><tr><td>Neutrino Mixing</td><td>1348</td></tr><tr><td>Heavy Neutral Leptons, Searches for</td><td>1367</td></tr></table>

## Notes in the Listings

<table><tr><td>Neutrino properties (rev.)</td><td>1332</td></tr><tr><td>Sum of neutrino masses (rev.)</td><td>1335</td></tr><tr><td>Number of light neutrino types from collider experiments</td><td>1341</td></tr><tr><td>Neutrinoless double-β decay</td><td>1343</td></tr></table>

## Related Reviews in Volume 1

<table><tr><td>56. Muon anomalous magnetic moment (rev.)</td><td>822</td></tr><tr><td>57. Muon decay parameters (rev.)</td><td>826</td></tr><tr><td>58. τ branching fractions (rev.)</td><td>829</td></tr><tr><td>59. τ-lepton decay parameters (rev.)</td><td>832</td></tr></table>
<figure><img src="image_408.png" /></figure>
# LEPTONS

e

$$J = \frac{1}{2}$$

## e MASS (atomic mass units u)

The primary determination of an electron's mass comes from measuring the ratio of the mass to that of a nucleus, so that the result is obtained in u (atomic mass units). The conversion factor to MeV is more uncertain than the mass of the electron in u; indeed, the recent improvements in the mass determination are not evident when the result is given in MeV. In this datablock we give the result in u, and in the following datablock in MeV.

<table><thead><tr><th>VALUE (10<sup>-6</sup> u)</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>548.579909065 ± 0.00000016</strong></td><td>TIESINGA</td><td>21</td><td>RVUE 2018 CODATA value</td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>548.579909070 ± 0.00000016</td><td>MOHR</td><td>16</td><td>RVUE 2014 CODATA value</td></tr><tr><td>548.57990946 ± 0.00000022</td><td>MOHR</td><td>12</td><td>RVUE 2010 CODATA value</td></tr><tr><td>548.57990943 ± 0.00000023</td><td>MOHR</td><td>08</td><td>RVUE 2006 CODATA value</td></tr><tr><td>548.57990945 ± 0.00000024</td><td>MOHR</td><td>05</td><td>RVUE 2002 CODATA value</td></tr><tr><td>548.5799092 ± 0.0000004</td><td><sup>1</sup>BEIER</td><td>02</td><td>CNTR Penning trap</td></tr><tr><td>548.5799110 ± 0.0000012</td><td>MOHR</td><td>99</td><td>RVUE 1998 CODATA value</td></tr><tr><td>548.5799111 ± 0.0000012</td><td><sup>2</sup>FARNHAM</td><td>95</td><td>CNTR Penning trap</td></tr><tr><td>548.579903 ± 0.000013</td><td>COHEN</td><td>87</td><td>RVUE 1986 CODATA value</td></tr></tbody></table>

¹BEIER 02 compares Larmor frequency of the electron bound in a $^{12}\text{C}^{5+}$ ion with the cyclotron frequency of a single trapped $^{12}\text{C}^{5+}$ ion.

²FARNHAM 95 compares cyclotron frequency of trapped electrons with that of a single trapped $^{12}\text{C}^{6+}$ ion.

## e MASS

The mass is known more precisely in u (atomic mass units) than in MeV. The conversion is: 1 u = 931.494 102 42(28) MeV/c² (2018 CODATA value, TIESINGA 21). The conversion error dominates the uncertainty of the masses given below.

<table><thead><tr><th>VALUE (MeV)</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>0.51099895000 ± 0.0000000015</strong></td><td>TIESINGA</td><td>21</td><td>RVUE 2018 CODATA value</td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>0.5109989461 ± 0.0000000031</td><td>MOHR</td><td>16</td><td>RVUE 2014 CODATA value</td></tr><tr><td>0.510998928 ± 0.00000011</td><td>MOHR</td><td>12</td><td>RVUE 2010 CODATA value</td></tr><tr><td>0.510998910 ± 0.00000013</td><td>MOHR</td><td>08</td><td>RVUE 2006 CODATA value</td></tr><tr><td>0.510998918 ± 0.00000044</td><td>MOHR</td><td>05</td><td>RVUE 2002 CODATA value</td></tr><tr><td>0.510998901 ± 0.00000020</td><td><sup>1,2</sup>BEIER</td><td>02</td><td>CNTR Penning trap</td></tr><tr><td>0.510998902 ± 0.00000021</td><td>MOHR</td><td>99</td><td>RVUE 1998 CODATA value</td></tr><tr><td>0.510998903 ± 0.00000020</td><td><sup>1,3</sup>FARNHAM</td><td>95</td><td>CNTR Penning trap</td></tr><tr><td>0.510998895 ± 0.00000024</td><td><sup>1</sup>COHEN</td><td>87</td><td>RVUE 1986 CODATA value</td></tr><tr><td>0.5110034 ± 0.000014</td><td>COHEN</td><td>73</td><td>RVUE 1973 CODATA value</td></tr></tbody></table>

¹Converted to MeV using the 1998 CODATA value of the conversion constant, 931.494013 ± 0.000037 MeV/u.

²BEIER 02 compares Larmor frequency of the electron bound in a $^{12}\text{C}^{5+}$ ion with the cyclotron frequency of a single trapped $^{12}\text{C}^{5+}$ ion.

³FARNHAM 95 compares cyclotron frequency of trapped electrons with that of a single trapped $^{12}\text{C}^{6+}$ ion.

## $(m_e^+ - m_e^-) / m_{\text{average}}$

A test of CPT invariance.

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>&lt;8 × 10<sup>-9</sup></strong></td><td>90</td><td><sup>1</sup>FEE</td><td>93</td><td>CNTR Positronium spectroscopy</td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td><td></td></tr><tr><td>&lt;4 × 10<sup>-23</sup></td><td>90</td><td><sup>2</sup>DOLGOV</td><td>14</td><td>From photon mass limit</td></tr><tr><td>&lt;4 × 10<sup>-8</sup></td><td>90</td><td>CHU</td><td>84</td><td>CNTR Positronium spectroscopy</td></tr></tbody></table>

¹FEE 93 value is obtained under the assumption that the positronium Rydberg constant is exactly half the hydrogen one.

²DOLGOV 14 result is obtained under the assumption that any mass difference between electron and positron would lead to a non-zero photon mass. The PDG 12 limit of $1 \times 10^{-18}$ eV on the photon mass is in turn used to derive the value quoted here.

## $|q_e^+ + q_e^-|/e$

A test of CPT invariance. See also similar tests involving the proton.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>&lt;4 × 10<sup>-8</sup></strong></td><td></td><td></td><td></td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>&lt;2 × 10<sup>-18</sup></td><td><sup>1</sup>HUGHES</td><td>92</td><td>RVUE</td></tr><tr><td>&lt;1 × 10<sup>-18</sup></td><td><sup>2</sup>SCHAEFER</td><td>95</td><td>THEO Vacuum polarization</td></tr><tr><td></td><td><sup>3</sup>MUELLER</td><td>92</td><td>THEO Vacuum polarization</td></tr></tbody></table>

¹HUGHES 92 uses recent measurements of Rydberg-energy and cyclotron-frequency ratios.

²SCHAEFER 95 removes model dependency of MUELLER 92.

³MUELLER 92 argues that an inequality of the charge magnitudes would, through higher-order vacuum polarization, contribute to the net charge of atoms.

## e MAGNETIC MOMENT ANOMALY

### $\mu_e/\mu_B = 1 - (g-2)/2$

<table><thead><tr><th>VALUE (units 10<sup>-6</sup>)</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>1159.65218062 ± 0.00000012</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td></tr><tr><td>1159.65218059 ± 0.00000013</td><td><sup>1</sup>FAN</td><td>23</td><td>MRS</td><td>Single electron</td></tr><tr><td>1159.65218073 ± 0.00000028</td><td>HANNEKE</td><td>08</td><td>MRS</td><td>Single electron</td></tr><tr><td>1159.6521884 ± 0.0000043</td><td>VANDYCK</td><td>87</td><td>MRS</td><td>Single electron</td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td><td></td></tr><tr><td>1159.65218128 ± 0.00000018</td><td>TIESINGA</td><td>21</td><td>RVUE</td><td>2018 CODATA value</td></tr><tr><td>1159.65218091 ± 0.00000026</td><td>MOHR</td><td>16</td><td>RVUE</td><td>2014 CODATA value</td></tr><tr><td>1159.65218076 ± 0.00000027</td><td>MOHR</td><td>12</td><td>RVUE</td><td>2010 CODATA value</td></tr><tr><td>1159.65218111 ± 0.00000074</td><td><sup>2</sup>MOHR</td><td>08</td><td>RVUE</td><td>2006 CODATA value</td></tr><tr><td>1159.65218085 ± 0.00000076</td><td><sup>3</sup>ODOM</td><td>06</td><td>MRS</td><td>Single electron</td></tr><tr><td>1159.6521859 ± 0.0000038</td><td>MOHR</td><td>05</td><td>RVUE</td><td>2002 CODATA value</td></tr><tr><td>1159.6521869 ± 0.0000041</td><td>MOHR</td><td>99</td><td>RVUE</td><td>1998 CODATA value</td></tr><tr><td>1159.652193 ± 0.000010</td><td>COHEN</td><td>87</td><td>RVUE</td><td>1986 CODATA value</td></tr><tr><td>1159.6521879 ± 0.0000043</td><td><sup>4</sup>VANDYCK</td><td>87</td><td>MRS</td><td>Single positron</td></tr></tbody></table>

¹FAN 23 report the most accurate measurement of the electron magnetic moment. A one-electron quantum cyclotron is used. We do not propagate at the moment this measurement to the fine structure and other physical constants. When discrepancies in the independent determinations of alpha are resolved, the new measurement uncertainty of 0.13 ppt is available for precise tests for BSM physics.

²MOHR 08 average is dominated by ODOM 06.

³Superseded by HANNEKE 08 per private communication with Gerald Gabriele.

⁴This VANDYCK 87 result is for a positron. We do not take it into account for the average to avoid the assumption of CPT invariance.

## $(g_e^+ - g_e^-) / g_{\text{average}}$

A test of CPT invariance.

<table><thead><tr><th>VALUE (units 10<sup>-12</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>-0.5 ± 2.1</strong></td><td></td><td><sup>1</sup>VANDYCK</td><td>87</td><td>MRS Penning trap</td></tr><tr><td>&lt; 12</td><td>95</td><td><sup>2</sup>VASSERMAN</td><td>87</td><td>CNTR Assumes $m_e^+ = m_e^-$</td></tr><tr><td>22 ± 64</td><td></td><td>SCHWINBERG</td><td>81</td><td>MRS Penning trap</td></tr></tbody></table>

¹VANDYCK 87 measured $(g_e^- - g_e^+)^{-1}$ and we converted it.

²VASSERMAN 87 measured $(g_e^+ - g_e^-)/(g^-)$. We multiplied by $(g^-)/g = 1.2 \times 10^{-3}$.

## e ELECTRIC DIPOLE MOMENT (d)

A nonzero value is forbidden by both *T* invariance and *P* invariance.

<table><thead><tr><th>VALUE (10<sup>-28</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>&lt; 0.041</strong></td><td>90</td><td><sup>1</sup> ROUSSY</td><td>23</td><td>ESR electrons in in-tramolecular electric field</td></tr><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td><td></td></tr><tr><td>&lt; 0.11</td><td>90</td><td><sup>2</sup> ANDREEV</td><td>18</td><td>CNTR ThO molecules</td></tr><tr><td>&lt; 1.3</td><td>90</td><td><sup>3</sup> CAIRNCROSS</td><td>17</td><td>ESR $^{180}\text{Hf}^{19}\text{F}$ molecules</td></tr><tr><td>- 5570 ± 7980 ± 120</td><td></td><td>KIM</td><td>15</td><td>CNTR $\text{Gd}_3\text{Ga}_2\text{O}_{12}$ molecules</td></tr><tr><td>&lt; 0.87</td><td>90</td><td><sup>4</sup> BARON</td><td>14</td><td>CNTR ThO molecules</td></tr><tr><td>&lt; 6050</td><td>90</td><td><sup>5</sup> ECKEL</td><td>12</td><td>CNTR Eu$_{0.5}$Ba$_{0.5}$TiO$_3$ molecules</td></tr><tr><td>&lt; 10.5</td><td>90</td><td><sup>6</sup> HUDSON</td><td>11</td><td>NMR YbF molecules</td></tr><tr><td>6.9 ± 7.4</td><td></td><td>REGAN</td><td>02</td><td>MRS $^{205}\text{Ti}$ beams</td></tr><tr><td>18 ± 12 ± 10</td><td></td><td><sup>7</sup> COMMINS</td><td>94</td><td>MRS $^{205}\text{Ti}$ beams</td></tr><tr><td>- 21 ± 83</td><td></td><td><sup>7</sup> ABDULLAH</td><td>90</td><td>MRS $^{205}\text{Ti}$ beams</td></tr><tr><td>- 1400 ± 2400</td><td></td><td>CHO</td><td>89</td><td>NMR TIF molecules</td></tr><tr><td>- 150 ± 550 ± 150</td><td></td><td>MURTHY</td><td>89</td><td>Cs, no B field</td></tr><tr><td>- 5000 ± 11000</td><td></td><td>LAMOREAUX</td><td>87</td><td>NMR $^{199}\text{Hg}$</td></tr><tr><td>19000 ± 34000</td><td>90</td><td>SANDARS</td><td>75</td><td>MRS Thallium</td></tr><tr><td>7000 ± 22000</td><td>90</td><td>PLAYER</td><td>70</td><td>MRS Xenon</td></tr><tr><td>&lt; 30000</td><td>90</td><td>WEISSKOPF</td><td>68</td><td>MRS Cesium</td></tr></tbody></table>

¹ROUSSY 23 gives a measurement corresponding to this limit as $(-1.3 \pm 2.0 \pm 0.6) \times 10^{-30}$ ecm.

²ANDREEV 18 gives a measurement corresponding to this limit as $(4.3 \pm 3.1 \pm 2.6) \times 10^{-30}$ ecm.

³CAIRNCROSS 17 gives a measurement corresponding to this limit as $(0.09 \pm 0.77 \pm 0.17) \times 10^{-28}$ ecm.

⁴BARON 14 gives a measurement corresponding to this limit as $(-0.21 \pm 0.37 \pm 0.25) \times 10^{-28}$ ecm.

⁵ECKEL 12 gives a measurement corresponding to this limit as $(-1.07 \pm 3.06 \pm 1.74) \times 10^{-25}$ ecm.

⁶HUDSON 11 gives a measurement corresponding to this limit as $(-2.4 \pm 5.7 \pm 1.5) \times 10^{-28}$ ecm.

⁷ABDULLAH 90, COMMINS 94, and REGAN 02 use the relativistic enhancement of a valence electron's electric dipole moment in a high-Z atom.
## e⁻ MEAN LIFE / BRANCHING FRACTION

A test of charge conservation. See the "Note on Testing Charge Conservation" and the Pauli Exclusion Principle" following this section in our 1992 edition (Physical Review **D45** S1 (1992), p. VI.10).

Most of these experiments are one of three kinds: Attempts to observe (a) the 255.5 keV gamma ray produced in $e^{-} \to \nu_{e}\gamma$, (b) the (K) shell x-ray produced when an electron decays without additional energy deposit, e.g., $e^{-} \to \nu_{e}\tau e^{-}\nu_{e}$ ("disappearance" experiments), and (c) nuclear de-excitation gamma rays after the electron disappears from an atomic shell and the nucleus is left in an excited state. The last can include both weak boson and photon mediating processes. We use the best $e^{-} \to \nu_{e}\gamma$ limit for the Summary Tables.

Note that we use the mean life rather than the half life, which is often reported.

### e → νeγ and astrophysical limits

<table><thead><tr><th>VALUE (yr)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&gt;6.6 × 10<sup>28</sup></td><td>90</td><td>AGOSTINI</td><td>15b</td><td>BORX e<sup>-</sup> → νγ</td></tr><tr><td>• • •</td><td colspan="4">We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&gt;1.22 × 10<sup>26</sup></td><td>68</td><td>1 KLAPDOR-K...</td><td>07</td><td>CNTR e<sup>-</sup> → νγ</td></tr><tr><td>&gt;4.6 × 10<sup>26</sup></td><td>90</td><td>BACK</td><td>02</td><td>BORX e<sup>-</sup> → νγ</td></tr><tr><td>&gt;3.4 × 10<sup>26</sup></td><td>68</td><td>BELLI</td><td>00b</td><td>DAMA e<sup>-</sup> → νγ, liquid Xe</td></tr><tr><td>&gt;3.7 × 10<sup>25</sup></td><td>68</td><td>AHARONOV</td><td>95b</td><td>CNTR e<sup>-</sup> → νγ</td></tr><tr><td>&gt;2.35 × 10<sup>25</sup></td><td>68</td><td>BALYSH</td><td>93</td><td>CNTR e<sup>-</sup> → νγ, 76<sup>Ge</sup> detector</td></tr><tr><td>&gt;1.5 × 10<sup>25</sup></td><td>68</td><td>AVIGNONE</td><td>86</td><td>CNTR e<sup>-</sup> → νγ</td></tr><tr><td>&gt;1 × 10<sup>39</sup></td><td>68</td><td>2 ORITO</td><td>85</td><td>ASTR Astrophysical argument</td></tr><tr><td>&gt;3 × 10<sup>23</sup></td><td>68</td><td>BELLOTTI</td><td>83b</td><td>CNTR e<sup>-</sup> → νγ</td></tr></tbody></table>

¹ The authors of A. Derbin et al, arXiv:0704.2047v1 argue that this limit is overestimated by at least a factor of 5.

² ORITO 85 assumes that electromagnetic forces extend out to large enough distances and that the age of our galaxy is 10¹⁰ years.

### Disappearance and nuclear-excitation experiments

<table><thead><tr><th>VALUE (yr)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&gt;6.4 × 10<sup>24</sup></td><td>68</td><td>1 BELLI</td><td>99b</td><td>DAMA De-excitation of 129<sup>Xe</sup></td></tr><tr><td>• • •</td><td colspan="4">We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&gt;1.2 × 10<sup>24</sup></td><td>90</td><td>ABGRALL</td><td>17</td><td>HPGE Ge K-shell disappearance</td></tr><tr><td>&gt;4.2 × 10<sup>24</sup></td><td>68</td><td>BELLI</td><td>99</td><td>DAMA Iodine L-shell disappearance</td></tr><tr><td>&gt;2.4 × 10<sup>23</sup></td><td>90</td><td>2 BELLI</td><td>99d</td><td>DAMA De-excitation of 127<sup>I</sup> (in NaI)</td></tr><tr><td>&gt;4.3 × 10<sup>23</sup></td><td>68</td><td>AHARONOV</td><td>95b</td><td>CNTR Ge K-shell disappearance</td></tr><tr><td>&gt;2.7 × 10<sup>23</sup></td><td>68</td><td>REUSSER</td><td>91</td><td>CNTR Ge K-shell disappearance</td></tr><tr><td>&gt;2 × 10<sup>22</sup></td><td>68</td><td>BELLOTTI</td><td>83b</td><td>CNTR Ge K-shell disappearance</td></tr></tbody></table>

¹ BELLI 99b limit on charge nonconserving $e^{-}$ capture involving excitation of the 236.1 keV nuclear state of 129<sup>Xe</sup>; the 90% CL limit is 3.7 × 10<sup>24</sup> yr. Less stringent limits for other states are also given.

² BELLI 99d limit on charge nonconserving $e^{-}$ capture involving excitation of the 57.6 keV nuclear state of 127<sup>I</sup>. Less stringent limits for the other states and for the state of 23<sup>Na</sup> are also given.

## LIMITS ON LEPTON-FLAVOR VIOLATION IN PRODUCTION

Forbidden by lepton family number conservation.

This section was added for the 2008 edition of this Review and is not complete. For a list of further measurements see references in the papers listed below.

### $\sigma(e^{+}e^{-} \to e^{\pm}\tau^{\mp}) / \sigma(e^{+}e^{-} \to \mu^{+}\mu^{-})$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;8.9 × 10<sup>-6</sup></td><td>95</td><td>AUBERT</td><td>07p</td><td>BABR e<sup>+</sup> e<sup>-</sup> at E<sub>cm</sub> = 10.58 GeV</td></tr><tr><td>• • •</td><td colspan="4">We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&lt;1.8 × 10<sup>-3</sup></td><td>95</td><td>GOMEZ-CAD...</td><td>91</td><td>MRK2 e<sup>+</sup> e<sup>-</sup> at E<sub>cm</sub> = 29 GeV</td></tr></tbody></table>

### $\sigma(e^{+}e^{-} \to \mu^{+}\tau^{\mp}) / \sigma(e^{+}e^{-} \to \mu^{+}\mu^{-})$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;4.0 × 10<sup>-6</sup></td><td>95</td><td>AUBERT</td><td>07p</td><td>BABR e<sup>+</sup> e<sup>-</sup> at E<sub>cm</sub> = 10.58 GeV</td></tr><tr><td>• • •</td><td colspan="4">We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&lt;6.1 × 10<sup>-3</sup></td><td>95</td><td>GOMEZ-CAD...</td><td>91</td><td>MRK2 e<sup>+</sup> e<sup>-</sup> at E<sub>cm</sub> = 29 GeV</td></tr></tbody></table>

## e REFERENCES

<table><tr><td>FAN</td><td>23</td><td>PRL 130 071801</td><td>(HARV, NWES)</td></tr><tr><td>ROUSSY</td><td>21</td><td>SCI 381 46</td><td>(COLO)</td></tr><tr><td>TIESINGA</td><td>23</td><td>RMP 93 025010</td><td>(NIST)</td></tr><tr><td>ANDREEV</td><td>18</td><td>NAT 562 355</td><td></td></tr><tr><td>ABGRALL</td><td>17</td><td>PRL 118 161801</td><td>(ACME Collab.)</td></tr><tr><td>CAIRNCROSS</td><td>17</td><td>PRL 119 153001</td><td>(MAJORANA Collab.)</td></tr><tr><td>MOHR</td><td>16</td><td>RMP 88 035009</td><td>(NIST)</td></tr><tr><td>AGOSTINI</td><td>15b</td><td>PRL 115 231802</td><td>(Borexino Collab.)</td></tr><tr><td>KIM</td><td>15</td><td>PR D91 102004</td><td>(IND, YALE, LANL)</td></tr><tr><td>BARON</td><td>14</td><td>SCI 343 269</td><td></td></tr><tr><td>DOLGOV</td><td>14</td><td>PL B732 244</td><td>(ACME Collab.)</td></tr><tr><td>ECKEL</td><td>12</td><td>PRL 109 193003</td><td></td></tr><tr><td>MOHR</td><td>12</td><td>RMP 84 1527</td><td>(NIST)</td></tr><tr><td>PDG</td><td>12</td><td>PR D86 010001</td><td>(PDG Collab.)</td></tr><tr><td>HUDSON</td><td>11</td><td>NAT 473 493</td><td>(LOIC)</td></tr><tr><td>HANNEKE</td><td>08</td><td>PRL 100 120801</td><td>(HARV)</td></tr></table>

<table><tr><td>MOHR</td><td>08</td><td>RMP 80 633</td><td>P.J. Mohr, B.N. Taylor, D.B. Newell (NIST)</td></tr><tr><td>AUBERT</td><td>07p</td><td>PR D75 031103</td><td>B. Aubert et al. (BABAR Collab.)</td></tr><tr><td>KLAPDOR-K...</td><td>07</td><td>PL B644 109</td><td>H.V. Klapdor-Kleingrothaus, I.V. Krivoshina, I.V. Titkova</td></tr><tr><td>ODOM</td><td>06</td><td>PRL 97 030801</td><td>B. Odom et al. (HARV)</td></tr><tr><td>MOHR</td><td>05</td><td>RMP 77 1</td><td>P.J. Mohr, B.N. Taylor (NIST)</td></tr><tr><td>BACK</td><td>02</td><td>PL B525 29</td><td>H.O. Back et al. (Borexino/SASSO Collab.)</td></tr><tr><td>BEIER</td><td>02</td><td>PRL 88 011603</td><td>T. Beier et al. (Reinhardt)</td></tr><tr><td>REGAN</td><td>02</td><td>PRL 88 071805</td><td>B.C. Regan et al. (FRAN)</td></tr><tr><td>BELLI</td><td>00b</td><td>PR D61 117301</td><td>P. Belli et al. (DAMA Collab.)</td></tr><tr><td>BELLI</td><td>99</td><td>PL B460 236</td><td>P. Belli et al. (DAMA Collab.)</td></tr><tr><td>BELLI</td><td>99b</td><td>PL B465 315</td><td>P. Belli et al. (DAMA Collab.)</td></tr><tr><td>BELLI</td><td>99d</td><td>PR C60 065501</td><td>P. Belli et al. (DAMA Collab.)</td></tr><tr><td>MOHR</td><td>99</td><td>JPCRD 28 1713</td><td>P.J. Mohr, B.N. Taylor (NIST)</td></tr><tr><td>Also</td><td></td><td>RMP 72 351</td><td>P.J. Mohr, B.N. Taylor (NIST)</td></tr><tr><td>AHARONOV</td><td>95b</td><td>PR D52 3785</td><td>Y. Aharonov et al. (SCUC, PNL, ZARA+)</td></tr><tr><td>Also</td><td></td><td>PL B353 168</td><td>Y. Aharonov et al. (SCUC, PNL, ZARA+)</td></tr><tr><td>FARNHAM</td><td>95</td><td>PRL 75 3598</td><td>D.L. Farnham, R.S. van Dyck, P.B. Schwinberg (WASH)</td></tr><tr><td>SCHAEFER</td><td>95</td><td>PR A51 838</td><td>A. Schaefer, J. Reinhardt (FRAN)</td></tr><tr><td>COMMINS</td><td>94</td><td>PR A50 2960</td><td>E.D. Commins et al. (KIAE, MPIK, SASSO)</td></tr><tr><td>BALYSH</td><td>93</td><td>PR A48 192</td><td>M.S. Fee et al. (LANL, AARH)</td></tr><tr><td>HUGHES</td><td>92</td><td>PRL 69 578</td><td>R.J. Hughes, B.I. Deutch (LANL, AARH)</td></tr><tr><td>MUELLER</td><td>92</td><td>PR 69 3432</td><td>B. Muller, M.H. Thoma (DUKE)</td></tr><tr><td>PDG</td><td>92</td><td>PR D45 S1</td><td>K. Hikasa et al. (KEK, LBL, BOST+)</td></tr><tr><td>GOMEZ-CAD...</td><td>91</td><td>PRL 66 1007</td><td>J.J. Gomez-Cadenas et al. (SLAC MARK-2 Collab.)</td></tr><tr><td>REUSSER</td><td>91</td><td>PL B255 143</td><td>D. Reusser et al. (NEUC, CIT, PSI)</td></tr><tr><td>ABDULLAH</td><td>90</td><td>PRL 65 2347</td><td>K. Abdullah et al. (LBL, UCB)</td></tr><tr><td>CHO</td><td>89</td><td>PRL 63 2559</td><td>D. Cho, K. Sangster, E.A. Hinds (YALE)</td></tr><tr><td>MURTHY</td><td>89</td><td>RMP 63 965</td><td>S.A. Murthy et al. (AMHT)</td></tr><tr><td>COHEN</td><td>87</td><td>RMP 59 1121</td><td>E.R. Cohen, B.N. Taylor (RISC, NBS)</td></tr><tr><td>LAMOREAUX</td><td>87</td><td>PRL 59 2275</td><td>S.K. Lamoreaux et al. (WASH)</td></tr><tr><td>VANDYCK</td><td>87</td><td>PRL 59 26</td><td>R.S. van Dyck, P.B. Schwinberg, H.G. Dehmelt (WASH)</td></tr><tr><td>VASSERMAN</td><td>87</td><td>PL B198 302</td><td>I.B. Vasserman et al. (NOVO)</td></tr><tr><td>Also</td><td></td><td>PL B107 172</td><td>I.B. Vasserman et al. (NOVO)</td></tr><tr><td>AVIGNONE</td><td>86</td><td>PR D34 97</td><td>F.T. Avignone et al. (PNL, SCUC)</td></tr><tr><td>ORITO</td><td>85</td><td>PRL 54 2457</td><td>S. Orito, M. Yoshimura (TOKY, KEK)</td></tr><tr><td>CHU</td><td>84</td><td>PRL 52 1689</td><td>S. Chu, A.P. Mills, J.L. Hall (BELL, NBS, COLO)</td></tr><tr><td>BELLOTTI</td><td>83b</td><td>PL P124 B 435</td><td>E. Bellotti et al. (MILA)</td></tr><tr><td>SCHWINBERG</td><td>81</td><td>PL 47 1679</td><td>P.B. Schwinberg, R.S. van Dyck, H.G. Dehmelt (WASH)</td></tr><tr><td>SANDARS</td><td>75</td><td>PR A11 473</td><td>P.G.H. Sandars, D.M. Sternheimer (OXF, BNL)</td></tr><tr><td>COHEN</td><td>73</td><td>JPCRD 2 664</td><td>E.R. Cohen, B.N. Taylor (RISC, NBS)</td></tr><tr><td>ORITO</td><td>70</td><td>JP B3 1620</td><td>M.A. Player, P.G.H. Sandars (OXF)</td></tr><tr><td>WEISSKOPF</td><td>68</td><td>PRL 21 1645</td><td>M.C. Weisskopf et al. (BRAN)</td></tr></table>

$\mu$

$$J = \frac{1}{2}$$

## μ MASS (atomic mass units u)

The muon's mass is obtained from the muon-electron mass ratio as determined from the measurement of Zeeman transition frequencies in muonium ($\mu^{+}e^{-}$ atom). Since the electron's mass is most accurately known in u, the muon's mass is also most accurately known in u. The conversion factor to MeV has approximately the same relative uncertainty as the mass of the muon in u. In this datablock we give the result in u, and in the following datablock in MeV.

<table><thead><tr><th>VALUE (u)</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>0.1134289259 ± 0.0000000025</td><td>TIESINGA</td><td>21</td><td>RVUE 2018 CODATA value</td></tr><tr><td>0.1134289257 ± 0.0000000025</td><td>MOHR</td><td>16</td><td>RVUE 2014 CODATA value</td></tr><tr><td>0.1134289267 ± 0.0000000029</td><td>MOHR</td><td>12</td><td>RVUE 2010 CODATA value</td></tr><tr><td>0.1134289256 ± 0.0000000029</td><td>MOHR</td><td>08</td><td>RVUE 2006 CODATA value</td></tr><tr><td>0.1134289264 ± 0.0000000030</td><td>MOHR</td><td>05</td><td>RVUE 2002 CODATA value</td></tr><tr><td>0.1134289168 ± 0.0000000034</td><td>1 MOHR</td><td>99</td><td>RVUE 1998 CODATA value</td></tr><tr><td>0.113428913 ± 0.000000017</td><td>2 COHEN</td><td>87</td><td>RVUE 1986 CODATA value</td></tr></tbody></table>

¹ MOHR 99 make use of other 1998 CODATA entries below.

² COHEN 87 make use of other 1986 CODATA entries below.

## μ MASS

The mass is known more precisely in u (atomic mass units) than in MeV.

The conversion is: $1 u = 931.494 102 42(28) \text{ MeV/c}^2$ (2018 CODATA value, TIESINGA 21). The conversion error contributes significantly to the uncertainty of the masses given below.

<table><thead><tr><th>VALUE (MeV)</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>105.6583755 ± 0.0000023</td><td>TIESINGA</td><td>21</td><td>RVUE</td><td>2018 CODATA value</td></tr><tr><td>• • •</td><td colspan="4">We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>105.6583745 ± 0.0000024</td><td>MOHR</td><td>16</td><td>RVUE</td><td>2014 CODATA value</td></tr><tr><td>105.6583715 ± 0.0000035</td><td>MOHR</td><td>12</td><td>RVUE</td><td>2010 CODATA value</td></tr><tr><td>105.6583668 ± 0.0000038</td><td>MOHR</td><td>08</td><td>RVUE</td><td>2006 CODATA value</td></tr><tr><td>105.6583692 ± 0.0000094</td><td>MOHR</td><td>05</td><td>RVUE</td><td>2002 CODATA value</td></tr><tr><td>105.6583568 ± 0.0000052</td><td>MOHR</td><td>99</td><td>RVUE</td><td>1998 CODATA value</td></tr><tr><td>105.658353 ± 0.000016</td><td>1 COHEN</td><td>87</td><td>RVUE</td><td>1986 CODATA value</td></tr><tr><td>105.658386 ± 0.000044</td><td>2 MARIAM</td><td>82</td><td>CNTR +</td><td></td></tr><tr><td>105.65836 ± 0.00026</td><td>3 CROWE</td><td>72</td><td>CNTR</td><td></td></tr><tr><td>105.65865 ± 0.00044</td><td>4 CRANE</td><td>71</td><td>CNTR</td><td></td></tr></tbody></table>

¹ Converted to MeV using the 1998 CODATA value of the conversion constant, 931.494013 ± 0.000037 MeV/u.

² MARIAM 82 give $m_{\mu}/m_{e} = 206.76825(62)$.

³ CROWE 72 give $m_{\mu}/m_{e} = 206.7682(5)$.

⁴ CRANE 71 give $m_{\mu}/m_{e} = 206.76878(85)$.
## μ MEAN LIFE τ

Measurements with an error > 0.001 × 10⁻⁶ s have been omitted.

<table><thead><tr><th>VALUE (10<sup>-6</sup> s)</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>2.1969811 ± 0.0000022 OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>2.1969803 ± 0.0000021 ± 0.0000007</td><td>1 TISHCHENKO</td><td>13</td><td>CNTR</td><td>Surface μ<sup>+</sup> at PSI</td></tr><tr><td>2.197083 ± 0.000032 ± 0.000015</td><td>BARCZYK</td><td>08</td><td>CNTR</td><td>Muons from π<sup>+</sup> decay at rest</td></tr><tr><td>2.197013 ± 0.000021 ± 0.000011</td><td>CHITWOOD</td><td>07</td><td>CNTR</td><td>Surface μ<sup>+</sup> at PSI</td></tr><tr><td>2.197078 ± 0.000073</td><td>BARDIN</td><td>84</td><td>CNTR</td><td></td></tr><tr><td>2.197025 ± 0.000155</td><td>BARDIN</td><td>84</td><td>CNTR</td><td></td></tr><tr><td>2.19695 ± 0.00006</td><td>GIOVANETTI</td><td>84</td><td>CNTR</td><td></td></tr><tr><td>2.19711 ± 0.00008</td><td>BALANDIN</td><td>74</td><td>CNTR</td><td></td></tr><tr><td>2.1973 ± 0.0003</td><td>DUCLOS</td><td>73</td><td>CNTR</td><td></td></tr><tr><td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>2.1969803 ± 0.0000022</td><td>WEBBER</td><td>11</td><td>CNTR</td><td>Surface μ<sup>+</sup> at PSI</td></tr><tr><td colspan="5"><sup>1</sup> TISHCHENKO 13 uses 1.6 × 10<sup>12</sup> μ<sup>+</sup> events and supersedes WEBBER 11.</td></tr></tbody></table>

## τμ⁺/τμ⁻ MEAN LIFE RATIO

A test of CPT invariance.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>1.000024 ± 0.000078</strong></td><td>BARDIN</td><td>84</td><td>CNTR</td></tr><tr><td colspan="4">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>1.0008 ± 0.0010</td><td>BAILEY</td><td>79</td><td>CNTR Storage ring</td></tr><tr><td>1.000 ± 0.001</td><td>MEYER</td><td>63</td><td>CNTR Mean life μ<sup>+</sup> / μ<sup>-</sup></td></tr></tbody></table>

## (τμ⁺ − τμ⁻) / τaverage

A test of CPT invariance. Calculated from the mean-life ratio, above.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th></tr></thead><tbody><tr><td>(2 ± 8) × 10<sup>-5</sup> OUR EVALUATION</td><td></td></tr></tbody></table>

## μ/p MAGNETIC MOMENT RATIO

This ratio is used to obtain a precise value of the muon mass and to reduce experimental muon Larmor frequency measurements to the muon magnetic moment anomaly. Measurements with an error > 0.00001 have been omitted. By convention, the minus sign on this ratio is omitted. CODATA values were fitted using their selection of data, plus other data from multiparameter fits.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>3.183345142 ± 0.00000071</strong></td><td>TIESINGA</td><td>21</td><td>RVUE</td><td>2018 CODATA value</td></tr><tr><td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>3.183345142 ± 0.00000071</td><td>MOHR</td><td>16</td><td>RVUE</td><td>2014 CODATA value</td></tr><tr><td>3.183345107 ± 0.00000084</td><td>MOHR</td><td>12</td><td>RVUE</td><td>2010 CODATA value</td></tr><tr><td>3.183345137 ± 0.00000085</td><td>MOHR</td><td>08</td><td>RVUE</td><td>2006 CODATA value</td></tr><tr><td>3.183345118 ± 0.00000089</td><td>MOHR</td><td>05</td><td>RVUE</td><td>2002 CODATA value</td></tr><tr><td>3.18334513 ± 0.00000039</td><td>LIU</td><td>99</td><td>CNTR</td><td>HFS in muonium</td></tr><tr><td>3.18334539 ± 0.00000010</td><td>MOHR</td><td>99</td><td>RVUE</td><td>1998 CODATA value</td></tr><tr><td>3.18334547 ± 0.00000047</td><td>COHEN</td><td>87</td><td>RVUE</td><td>1986 CODATA value</td></tr><tr><td>3.1833441 ± 0.0000017</td><td>KLEMPT</td><td>82</td><td>CNTR</td><td>Precession strob</td></tr><tr><td>3.1833461 ± 0.0000011</td><td>MARIAM</td><td>82</td><td>CNTR</td><td>HFS splitting</td></tr><tr><td>3.1833448 ± 0.0000029</td><td>CAMANI</td><td>78</td><td>CNTR</td><td>See KLEMPT 82</td></tr><tr><td>3.1833403 ± 0.0000044</td><td>CASPERSON</td><td>77</td><td>CNTR</td><td>HFS splitting</td></tr><tr><td>3.1833402 ± 0.0000072</td><td>COHEN</td><td>73</td><td>RVUE</td><td>1973 CODATA value</td></tr><tr><td>3.1833467 ± 0.0000082</td><td>CROWE</td><td>72</td><td>CNTR</td><td>Precession phase</td></tr></tbody></table>

See the related review(s):

Muon Anomalous Magnetic Moment

## μ MAGNETIC MOMENT ANOMALY

The parity-violating decay of muons in a storage ring is observed. The difference frequency $\omega_a$ between the muon spin precision and the orbital angular frequency ($e/m_\mu c$)($B$) is measured, as is the free proton NMR frequency $\omega_p$, thus determining the ratio $R=\omega_a/\omega_p$. Given the magnetic moment ratio $\lambda=\mu_\mu/\mu_p$ (from hyperfine structure in muonium), $(g-2)/2 = R/(\lambda-R)$.

### μμ/(eħ/2mμ)−1 = (gμ−2)/2

<table><thead><tr><th>VALUE (units 10<sup>-10</sup>)</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>11659205.9 ± 2.2</strong></td><td>1 AGUILLARD</td><td>23</td><td>MUG2 ±</td><td>Combined FNAL and BNL values</td></tr><tr><td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>11659205.5 ± 2.4</td><td>2 AGUILLARD</td><td>23</td><td>MUG2 ±</td><td>Storage ring</td></tr><tr><td>11659204.0 ± 5.4</td><td>ABI</td><td>21</td><td>MUG2 ±</td><td>Storage ring</td></tr><tr><td>11659206.1 ± 4.1</td><td>3 ABI</td><td>21</td><td>MUG2 ±</td><td>Combined FNAL and BNL values</td></tr><tr><td>11659208.0 ± 5.4 ± 3.3</td><td>BENNETT</td><td>06</td><td>MUG2 ±</td><td>Average μ<sup>+</sup> and μ<sup>-</sup></td></tr></tbody></table>

<table><tbody><tr><td>11659208 ± 6</td><td>BENNETT</td><td>04</td><td>MUG2 ±</td><td>Average μ<sup>+</sup> and μ<sup>-</sup></td></tr><tr><td>11659214 ± 8 ± 3</td><td>BENNETT</td><td>04</td><td>MUG2 -</td><td>Storage ring</td></tr><tr><td>11659203 ± 6 ± 5</td><td>BENNETT</td><td>04</td><td>MUG2 +</td><td>Storage ring</td></tr><tr><td>11659204 ± 7 ± 5</td><td>BENNETT</td><td>02</td><td>MUG2 +</td><td>Storage ring</td></tr><tr><td>11659202 ± 14 ± 6</td><td>BROWN</td><td>01</td><td>MUG2 +</td><td>Storage ring</td></tr><tr><td>11659191 ± 59</td><td>BROWN</td><td>00</td><td>MUG2 +</td><td></td></tr><tr><td>11659100 ± 110</td><td>4 BAILEY</td><td>79</td><td>CNTR -</td><td>Storage ring</td></tr><tr><td>11659360 ± 120</td><td>4 BAILEY</td><td>79</td><td>CNTR +</td><td></td></tr><tr><td>11659230 ± 85</td><td>4 BAILEY</td><td>79</td><td>CNTR ±</td><td>Storage ring</td></tr><tr><td>11620000 ± 5000</td><td>CHARPAK</td><td>62</td><td>CNTR +</td><td></td></tr></tbody></table>

1. AGUILLARD 23 combined their value with the previous independent BNL measurement of BENNETT 06.

2. This AGUILLARD 23 value is the combination of all 2018, 2019 and 2020 data, including the ABI 21 value. The new FNAL 2019 and 2020 data alone combined yield (11659205.7 ± 2.5) × 10⁻¹⁰.

3. ABI 21 combined their value with the previous independent BNL measurement of BENNETT 06. ABI 21 also report that the difference of this combination with the standard model value of (11659181.0 ± 4.3) × 10⁻¹⁰ (AOYAMA 20) has a significance of 4.2 σ.

4. BAILEY 79 values recalculated by HUGHES 99 using the COHEN 87 μ/p magnetic moment. The improved MOHR 99 value does not change the result.

## (gμ⁺ − gμ⁻) / gaverage

A test of CPT invariance.

<table><thead><tr><th>VALUE (units 10<sup>-8</sup>)</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>-0.11 ± 0.12</strong></td><td>BENNETT</td><td>04</td><td>MUG2</td><td></td></tr><tr><td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>-2.6 ± 1.6</td><td>BAILEY</td><td>79</td><td>CNTR</td><td></td></tr></tbody></table>

## μ ELECTRIC DIPOLE MOMENT (d)

A nonzero value is forbidden by both T invariance and P invariance.

<table><thead><tr><th>VALUE (10<sup>-19</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>&lt; 1.8</strong></td><td>95</td><td>1 BENNETT</td><td>09</td><td>MUG2 ±</td><td>Storage ring</td></tr><tr><td colspan="6">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&lt; 0.19</td><td>90</td><td>2 EMA</td><td>22</td><td></td><td>theory limit</td></tr><tr><td>-0.1 ± 1.0</td><td></td><td>3 BENNETT</td><td>09</td><td>MUG2 +</td><td>Storage ring</td></tr><tr><td>-0.1 ± 0.7</td><td></td><td>4 BENNETT</td><td>09</td><td>MUG2 -</td><td>Storage ring</td></tr><tr><td>-3.7 ± 3.4</td><td></td><td>5 BAILEY</td><td>78</td><td>CNTR ±</td><td>Storage ring</td></tr><tr><td>8.6 ± 4.5</td><td></td><td>BAILEY</td><td>78</td><td>CNTR +</td><td>Storage ring</td></tr><tr><td>0.8 ± 4.3</td><td></td><td>BAILEY</td><td>78</td><td>CNTR -</td><td>Storage ring</td></tr></tbody></table>

1. This is the combination of the two BENNETT 09 measurements quoted here separately for μ⁺ and μ⁻. The result is also presented as a measurement of (0.0 ± 0.9) × 10⁻¹⁹ e cm.

2. EMA 22 determine indirect constraints on |μ<sub>EDM</sub>| from EDM measurements performed on heavy atoms and molecules, based on the muon-loop induced light-by-light CP-odd amplitude.

3. Also reported as the limit of |d(μ<sup>+</sup>)| < 2.1 × 10⁻¹⁹ e cm at 95% CL.

4. Also reported as the limit of |d(μ<sup>-</sup>)| < 1.5 × 10⁻¹⁹ e cm at 95% CL.

5. This is the combination of the two BAILEY 78 results quoted here separately for μ⁺ and μ⁻. BAILEY 78 uses the convention d = 1/2 · (d<sub>μ⁺</sub> - d<sub>μ⁻</sub>) and reports 3.7 ± 3.4. We convert their result to use the same convention as BENNETT 09.

## MUON-ELECTRON CHARGE RATIO ANOMALY qμ⁺/qe⁻ + 1

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>(1.1 ± 2.1) × 10<sup>-9</sup></strong></td><td>1 MEYER</td><td>00</td><td>CNTR +</td><td>1s-2s muonium interval</td></tr></tbody></table>

1. MEYER 00 measures the 1s-2s muonium interval, and then interpret the result in terms of muon-electron charge ratio q<sub>μ⁺</sub>/q<sub>e⁻</sub>.

## μ⁻ DECAY MODES

μ⁺ modes are charge conjugates of the modes below.

<table><thead><tr><th>Mode</th><th>Fraction (Γ<sub>f</sub>/Γ)</th><th>Confidence level</th></tr></thead><tbody><tr><td>Γ<sub>1</sub> e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub></td><td>≈ 100%</td><td></td></tr><tr><td>Γ<sub>2</sub> e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub>γ</td><td>[a] (6.0 ± 0.5) × 10<sup>-8</sup></td><td></td></tr><tr><td>Γ<sub>3</sub> e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub> e<sup>+</sup>e<sup>-</sup></td><td>[b] (3.4 ± 0.4) × 10<sup>-5</sup></td><td></td></tr><tr><td colspan="3"><strong>Lepton Family number (LF) violating modes</strong></td></tr><tr><td>Γ<sub>4</sub> e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub></td><td>LF [c] &lt; 1.2 %</td><td>90%</td></tr><tr><td>Γ<sub>5</sub> e<sup>-</sup>γ</td><td>LF &lt; 4.2 × 10<sup>-13</sup></td><td>90%</td></tr><tr><td>Γ<sub>6</sub> e<sup>-</sup> e<sup>+</sup> e<sup>-</sup></td><td>LF &lt; 1.0 × 10<sup>-12</sup></td><td>90%</td></tr><tr><td>Γ<sub>7</sub> e<sup>-</sup>2γ</td><td>LF &lt; 7.2 × 10<sup>-11</sup></td><td>90%</td></tr></tbody></table>

[a] This only includes events with energy of e > 45 MeV and energy of γ > 40 MeV. Since the e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub> and e<sup>-</sup>ν<sub>e</sub>ν<sub>μ</sub>γ modes cannot be clearly separated, we regard the latter mode as a subset of the former.

[b] See the Particle Listings below for the energy limits used in this measurement.

[c] A test of additive vs. multiplicative lepton family number conservation.
## μ⁻ BRANCHING RATIOS

$\Gamma(e^{-}\bar{\nu}_{\mu}\gamma)/\Gamma_{\text{total}}$

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>(6.03±0.14±0.53) × 10<sup>-8</sup></td><td>13k</td><td>1 BALDINI</td><td>16A</td><td>SPEC</td><td>γ KE > 40 MeV</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>862</td><td>BOGART</td><td>67</td><td>CNTR</td><td>γ KE > 14.5 MeV</td></tr><tr><td>(3.3 ±1.3)</td><td>× 10<sup>-3</sup></td><td>CRITTENDEN</td><td>61</td><td>CNTR</td><td>γ KE > 20 MeV</td></tr><tr><td>(1.4 ±0.4)</td><td>× 10<sup>-2</sup></td><td>CRITTENDEN</td><td>61</td><td>CNTR</td><td>γ KE > 10 MeV</td></tr><tr><td></td><td>27</td><td>ASHKIN</td><td>59</td><td>CNTR</td><td></td></tr></tbody></table>

¹ BALDINI 16 measurement refers to $\mu^+ \to e^+\nu\bar{\nu}\gamma$ decay and requires energy of $e^+ > 45$ MeV and energy $\gamma > 40$ MeV.

$\Gamma(e^{-}\bar{\nu}_{\mu}e^{+}e^{-})/\Gamma_{\text{total}}$

<table><thead><tr><th>VALUE (units 10<sup>-5</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>3.4±0.2±0.3</td><td>7443</td><td>1 BERTL</td><td>85</td><td>SPEC</td><td>SINDRUM</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>7</td><td>2 CRITTENDEN</td><td>61</td><td>HLBC</td><td>E(e<sup>+</sup>e<sup>-</sup>) > 10 MeV</td></tr><tr><td>2.2±1.5</td><td>7</td><td>2 CRITTENDEN</td><td>61</td><td>HLBC</td><td></td></tr><tr><td>2</td><td>1</td><td>3 GUREVICH</td><td>60</td><td>EMUL</td><td></td></tr><tr><td>1.5±1.0</td><td>3</td><td>4 LEE</td><td>59</td><td>HBC</td><td></td></tr></tbody></table>

¹ BERTL 85 has transverse momentum cut $p_T > 17$ MeV/c. Systematic error was increased by us.

² CRITTENDEN 61 count only those decays where total energy of either $(e^+, e^-)$ combination is >10 MeV.

³ GUREVICH 60 interpret their event as either virtual or real photon conversion. $e^+$ and $e^-$ energies not measured.

⁴ In the three LEE 59 events, the sum of energies $E(e^+)$ + $E(e^-)$ + $E(e^+)$ was 51 MeV, 55 MeV, and 33 MeV.

$\Gamma(e^{-}\bar{\nu}_{\mu})/\Gamma_{\text{total}}$

Forbidden by the additive conservation law for lepton family number. A multiplicative law predicts this branching ratio to be 1/2. For a review see NEMETHY 81.

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 0.012</td><td>90</td><td>1 FREEDMAN</td><td>93</td><td>CNTR</td><td>ν oscillation search</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>KRAKAUER</td><td>91B</td><td>CALO</td><td></td></tr><tr><td>< 0.018</td><td>90</td><td>1 FREEDMAN</td><td>93</td><td>CNTR</td><td></td></tr><tr><td>< 0.05</td><td>90</td><td>2 BERGSMA</td><td>83</td><td>CALO</td><td>τ<sub>μ</sub> e → μ<sup>-</sup>ν<sub>e</sub></td></tr><tr><td>< 0.09</td><td>90</td><td>3 BERGSMA</td><td>83</td><td>CALO</td><td>See BERGSMA 83</td></tr><tr><td>-0.001 ± 0.061</td><td>90</td><td>JONKER</td><td>80</td><td>CALO</td><td></td></tr><tr><td>0.13 ± 0.15</td><td>90</td><td>WILLIS</td><td>80</td><td>CNTR</td><td></td></tr><tr><td></td><td>90</td><td>BLIETSCHAU</td><td>78</td><td>HLBC</td><td>Avg. of 4 values</td></tr><tr><td>< 0.25</td><td>90</td><td>EICHTEN</td><td>73</td><td>HLBC</td><td></td></tr></tbody></table>

¹ FREEDMAN 93 limit on $\bar{\nu}_e$ observation is here interpreted as a limit on lepton family number violation.

² BERGSMA 83 gives a limit on the inverse muon decay cross-section ratio $\sigma(\bar{\nu}_{\mu} e^- \to \mu^- \bar{\nu}_e)/\sigma(\nu_{\mu} e^- \to \mu^- \nu_e)$, which is essentially equivalent to $\Gamma(e^{-}\bar{\nu}_{\mu})/\Gamma_{\text{total}}$ for small values like that quoted.

$\Gamma(e^{-}\gamma)/\Gamma_{\text{total}}$

Forbidden by lepton family number conservation.

<table><thead><tr><th>VALUE (units 10<sup>-11</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 0.042</td><td>90</td><td>1 BALDINI</td><td>16</td><td>SPEC</td><td>MEG at PSI</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>ADAM</td><td>13b</td><td>SPEC</td><td>MEG at PSI</td></tr><tr><td>< 0.057</td><td>90</td><td>ADAM</td><td>11</td><td>SPEC</td><td>MEG at PSI</td></tr><tr><td>< 0.24</td><td>90</td><td>ADAM</td><td>10</td><td>SPEC</td><td>MEG at PSI</td></tr><tr><td>< 2.8</td><td>90</td><td>ADAM</td><td>9</td><td>SPEC</td><td></td></tr><tr><td>< 1.2</td><td>90</td><td>AHMED</td><td>02</td><td>SPEC</td><td>MEGA</td></tr><tr><td>< 1.2</td><td>90</td><td>BROOKS</td><td>99</td><td>SPEC</td><td>LAMPF</td></tr><tr><td>< 4.9</td><td>90</td><td>BOLTON</td><td>88</td><td>CBOX</td><td>LAMPF</td></tr><tr><td><100</td><td>90</td><td>AZUELOS</td><td>83</td><td>CNTR</td><td>TRIUMF</td></tr><tr><td>< 17</td><td>90</td><td>KINNISON</td><td>82</td><td>SPEC</td><td>LAMPF</td></tr><tr><td><100</td><td>90</td><td>SCHAAF</td><td>80</td><td>ELEC</td><td>SIN</td></tr></tbody></table>

$\Gamma(e^{-}e^{+}e^{-})/\Gamma_{\text{total}}$

Forbidden by lepton family number conservation.

<table><thead><tr><th>VALUE (units 10<sup>-12</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 1.0</td><td>90</td><td>1 BELLGARDT</td><td>88</td><td>SPEC</td><td>SINDRUM</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>ADAM</td><td>13b</td><td>SPEC</td><td>ARES</td></tr><tr><td>< 35</td><td>90</td><td>BOLTON</td><td>88</td><td>CBOX</td><td>LAMPF</td></tr><tr><td>< 2.4</td><td>90</td><td>1 BERTL</td><td>85</td><td>SPEC</td><td>SINDRUM</td></tr><tr><td><160</td><td>90</td><td>1 BERTL</td><td>84</td><td>SPEC</td><td>SINDRUM</td></tr><tr><td><130</td><td>90</td><td>1 BERTL</td><td>84</td><td>CNTR</td><td>LAMPF</td></tr></tbody></table>

¹ These experiments assume a constant matrix element.

$\Gamma(e^{-}2\gamma)/\Gamma_{\text{total}}$

Forbidden by lepton family number conservation.

<table><thead><tr><th>VALUE (units 10<sup>-11</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 7.2</td><td>90</td><td>1 BALDINI</td><td>20</td><td>MEG</td><td>PSI</td></tr><tr><td>< 1</td><td>90</td><td>2 AZUELOS</td><td>83</td><td>CNTR</td><td>TRIUMF</td></tr><tr><td>< 840</td><td>90</td><td>3 BOWMAN</td><td>78</td><td>CNTR</td><td>DEPOMMIER 77 data</td></tr><tr><td><5000</td><td>90</td><td>3 BOWMAN</td><td>78</td><td>CNTR</td><td>DEPOMMIER 77 data</td></tr></tbody></table>

¹ BALDINI 20 uses 7.5×10¹⁴ stopped muons to obtain limits on $\mu \to eX$ decay mediated by a new light particle X with lifetimes < 40 ps, which decays to $\gamma\gamma$ for X-mass ranges 20-45 MeV. The limit of the order < 10⁻¹¹ at 90% CL is for the mass range 20-30 MeV.

## LIMIT ON $\mu^{-} \to e^{-}$ CONVERSION

Forbidden by lepton family number conservation.

$\sigma(\mu^{-}32S \to e^{-}32S) / \sigma(\mu^{-}32S \to \nu_{\mu}32P^{*})$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 7 × 10<sup>-11</sup></td><td>90</td><td>BADERT...</td><td>80</td><td>STRC SIN</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>BADERT...</td><td>77</td><td>STRC SIN</td></tr><tr><td>< 4 × 10<sup>-10</sup></td><td>90</td><td>BADERT...</td><td>77</td><td>STRC SIN</td></tr></tbody></table>

$\sigma(\mu^{-}Cu \to e^{-}Cu) / \sigma(\mu^{-}Cu \to capture)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 1.6 × 10<sup>-8</sup></td><td>90</td><td>BRYMAN</td><td>72</td><td>SPEC</td></tr></tbody></table>

$\sigma(\mu^{-}Ti \to e^{-}Ti) / \sigma(\mu^{-}Ti \to capture)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 4.3 × 10<sup>-12</sup></td><td>90</td><td>1 DOHMEN</td><td>93</td><td>SINDRUM II</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>AHMAD</td><td>88</td><td>TPC TRIUMF</td></tr><tr><td>< 4.6 × 10<sup>-12</sup></td><td>90</td><td>AHMAD</td><td>88</td><td>TPC TRIUMF</td></tr><tr><td>< 1.6 × 10<sup>-11</sup></td><td>90</td><td>BRYMAN</td><td>85</td><td>TPC TRIUMF</td></tr></tbody></table>

¹ DOHMEN 93 assumes $\mu^{-} \to e^{-}$ conversion leaves the nucleus in its ground state, a process enhanced by coherence and expected to dominate.

$\sigma(\mu^{-}Pb \to e^{-}Pb) / \sigma(\mu^{-}Pb \to capture)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 4.6 × 10<sup>-11</sup></td><td>90</td><td>HONECKER</td><td>96</td><td>SPEC SINDRUM II</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>AHMAD</td><td>88</td><td>TPC TRIUMF</td></tr><tr><td>< 4.9 × 10<sup>-10</sup></td><td>90</td><td>AHMAD</td><td>88</td><td>TPC TRIUMF</td></tr></tbody></table>

$\sigma(\mu^{-}Au \to e^{-}Au) / \sigma(\mu^{-}Au \to capture)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 7 × 10<sup>-13</sup></td><td>90</td><td>BERTL</td><td>06</td><td>SPEC</td><td>SINDRUM II</td></tr></tbody></table>

## LIMIT ON $\mu^{-} \to e^{+}$ CONVERSION

Forbidden by total lepton number conservation.

$\sigma(\mu^{-}32S \to e^{+}32Si^{*}) / \sigma(\mu^{-}32S \to \nu_{\mu}32P^{*})$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 9 × 10<sup>-10</sup></td><td>90</td><td>BADERT...</td><td>80</td><td>STRC SIN</td></tr><tr><td>• • •</td><td></td><td></td><td></td><td></td></tr><tr><td></td><td>90</td><td>BADERT...</td><td>78</td><td>STRC SIN</td></tr><tr><td>< 1.5 × 10<sup>-9</sup></td><td>90</td><td>BADERT...</td><td>78</td><td>STRC SIN</td></tr></tbody></table>

$\sigma(\mu^{-}127I \to e^{+}127Sb^{*}) / \sigma(\mu^{-}127I \to anything)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 3 × 10<sup>-10</sup></td><td>90</td><td>1 ABELA</td><td>80</td><td>CNTR Radiochemical tech.</td></tr></tbody></table>

¹ ABELA 80 is upper limit for $\mu^{-}e^{+}$ conversion leading to particle-stable states of $^{127}$Sb. Limit for total conversion rate is higher by a factor less than 4 (G. Backenstoss, private communication).

$\sigma(\mu^{-}Cu \to e^{+}Co) / \sigma(\mu^{-}Cu \to \nu_{\mu}Ni)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 2.6 × 10<sup>-8</sup></td><td>90</td><td>BRYMAN</td><td>72</td><td>SPEC</td></tr><tr><td>< 2.2 × 10<sup>-7</sup></td><td>90</td><td>CONFORTO</td><td>62</td><td>OSPK</td></tr></tbody></table>

$\sigma(\mu^{-}Ti \to e^{+}Ca) / \sigma(\mu^{-}Ti \to capture)$

<table><thead><tr><th>VALUE</th><th>CL%</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>< 3.6 × 10<sup>-11</sup></td><td>90</td><td>1</td><td>1,2 KAULARD</td><td>98</td><td>SPEC</td><td>SINDRUM II</td></tr><tr><td>< 1.7 × 10<sup>-12</sup></td><td>90</td><td>1</td><td>2,3 KAULARD</td><td>98</td><td>SPEC</td><td>SINDRUM II</td></tr><tr><td>< 4.3 × 10<sup>-12</sup></td><td>90</td><td>3 DOHMEN</td><td>93</td><td>SPEC</td><td>SINDRUM II</td></tr><tr><td>< 8.9 × 10<sup>-11</sup></td><td>90</td><td>1 DOHMEN</td><td>93</td><td>SPEC</td><td>SINDRUM II</td></tr><tr><td>< 1.7 × 10<sup>-10</sup></td><td>90</td><td>4 AHMAD</td><td>88</td><td>TPC TRIUMF</td><td></td></tr></tbody></table>

¹ This limit assumes a giant resonance excitation of the daughter Ca nucleus (mean energy and width both 20 MeV).

² KAULARD 98 obtained these same limits using the unified classical analysis of FELDMAN 98.

³ This limit assumes the daughter Ca nucleus is left in the ground state. However, the probability of this is unknown.

⁴ Assuming a giant-resonance-excitation model.

<footnote n="2">² AZUELOS 83 uses the phase space distribution of BOWMAN 78.</footnote>

<footnote n="3">³ BOWMAN 78 assumes an interaction Lagrangian local on the scale of the inverse $\mu$ mass.</footnote>
## LIMIT ON MUONIUM → ANTIMUONIUM CONVERSION

Forbidden by lepton family number conservation.

$$R_g = G_c / G_f$$

The effective Lagrangian for the $\mu^+e^- \to \mu^-e^+$ conversion is assumed to be

$$\mathcal{L} = 2^{-1/2} G_C [\bar{\psi}_{\mu} \gamma_\lambda (1 - \gamma_5) \psi_e] [\bar{\psi}_{\mu} \gamma_\lambda (1 - \gamma_5) \psi_e] + \text{h.c.}$$

The experimental result is then an upper limit on $G_C/G_F$, where $G_F$ is the Fermi coupling constant.

<table><thead><tr><th>VALUE</th><th>CL%</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt; 0.0030</td><td>90</td><td>1</td><td>1 WILLMANN</td><td>99</td><td>SPEC</td><td>+ μ<sup>+</sup> at 26 GeV/c</td></tr><tr><td colspan="7">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>&lt; 0.14</td><td>90</td><td>1</td><td>2 GORDEEV</td><td>97</td><td>SPEC</td><td>+ JINR phasotron</td></tr><tr><td>&lt; 0.018</td><td>90</td><td>0</td><td>3 ABELA</td><td>96</td><td>SPEC</td><td>+ μ<sup>+</sup> at 24 MeV</td></tr><tr><td>&lt; 6.9</td><td>90</td><td></td><td>NI</td><td>93</td><td>CBOX</td><td>LAMPF</td></tr><tr><td>&lt; 0.16</td><td>90</td><td></td><td>MATTHIAS</td><td>91</td><td>SPEC</td><td>LAMPF</td></tr><tr><td>&lt; 0.29</td><td>90</td><td></td><td>HUBER</td><td>90B</td><td>CNTR</td><td>TRIUMF</td></tr><tr><td>&lt;20</td><td>95</td><td></td><td>BEER</td><td>86</td><td>CNTR</td><td>TRIUMF</td></tr><tr><td>&lt;42</td><td>95</td><td></td><td>MARSHALL</td><td>82</td><td>CNTR</td><td></td></tr></tbody></table>

1. WILLMANN 99 quote both probability $P_{MM} < 8.3 \times 10^{-11}$ at 90% CL in a 0.1 T field and $R_g = G_C/G_F$.

2. GORDEEV 97 quote limits on both $f=G_M/M/G_F$ and the probability $W_{MM} < 4.7 \times 10^{-7}$ (90% CL).

3. ABELA 96 quote both probability $P_{MM} < 8 \times 10^{-9}$ at 90% CL and $R_g = G_C/G_F$.

## See the related review(s):

### Muon Decay Parameters

## μ DECAY PARAMETERS

### ρ PARAMETER

(V-A) theory predicts $\rho = 0.75$.

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>0.74979 ± 0.00026</td><td>OUR AVERAGE</td><td></td><td></td><td></td><td></td></tr><tr><td>0.74977 ± 0.00012 ± 0.00023</td><td></td><td>1 BAYES</td><td>11</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td>0.7518 ± 0.0026</td><td></td><td>DERENZO</td><td>69</td><td>RVUE</td><td></td></tr><tr><td colspan="6">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>0.75014 ± 0.00017 ± 0.00045</td><td></td><td>2 MACDONALD</td><td>08</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td>0.75080 ± 0.00032 ± 0.00100</td><td></td><td>3 MUSSER</td><td>05</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td>0.72 ± 0.06 ± 0.08</td><td></td><td>AMORUSO</td><td>04</td><td>ICAR</td><td>Liquid Ar TPC</td></tr><tr><td>0.762 ± 0.008</td><td></td><td>4 FRYBERGER</td><td>68</td><td>ASPK</td><td>+ 25-53 MeV e<sup>+</sup></td></tr><tr><td>0.760 ± 0.009</td><td></td><td>4 SHERWOOD</td><td>67</td><td>ASPK</td><td>+ 25-53 MeV e<sup>+</sup></td></tr><tr><td>0.7503 ± 0.0026</td><td></td><td>4 PEOPLES</td><td>66</td><td>ASPK</td><td>+ 20-53 MeV e<sup>+</sup></td></tr></tbody></table>

1. The quoted systematic error includes a contribution of 0.00013 (added in quadrature) from uncertainties on radiative corrections and on the Michel parameter $\eta$.

2. The quoted systematic error includes a contribution of 0.00011 (added in quadrature) from the dependence on the Michel parameter $\eta$.

3. The quoted systematic error includes a contribution of 0.00023 (added in quadrature) from the dependence on the Michel parameter $\eta$.

4. $\eta$ constrained = 0. These values incorporated into a two parameter fit to $\rho$ and $\eta$ by DERENZO 69.

### η PARAMETER

(V-A) theory predicts $\eta = 0$.

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>0.057 ± 0.034</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>0.071 ± 0.037 ± 0.0005</td><td>30M</td><td>DANNEBERG</td><td>05</td><td>CNTR</td><td>+ 7-53 MeV e<sup>+</sup></td></tr><tr><td>0.011 ± 0.081 ± 0.026</td><td>5.3M</td><td>1 BURKARD</td><td>85bCNTR</td><td></td><td>+ 9-53 MeV e<sup>+</sup></td></tr><tr><td>-0.12 ± 0.21</td><td>6346</td><td>DERENZO</td><td>69</td><td>HBC</td><td>+ 1.6-6.8 MeV e<sup>+</sup></td></tr><tr><td colspan="6">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>-0.0021 ± 0.0070 ± 0.0010</td><td>30M</td><td>2 DANNEBERG</td><td>05</td><td>CNTR</td><td>+ 7-53 MeV e<sup>+</sup></td></tr><tr><td>-0.012 ± 0.015 ± 0.003</td><td>5.3M</td><td>2 BURKARD</td><td>85bCNTR</td><td></td><td>+ 9-53 MeV e<sup>+</sup></td></tr><tr><td>-0.007 ± 0.013</td><td>5.3M</td><td>3 BURKARD</td><td>85bFIT</td><td></td><td>+ 9-53 MeV e<sup>+</sup></td></tr><tr><td>-0.7 ± 0.5</td><td>170k</td><td>4 FRYBERGER</td><td>68</td><td>ASPK</td><td>+ 25-53 MeV e<sup>+</sup></td></tr><tr><td>-0.7 ± 0.6</td><td>280k</td><td>4 SHERWOOD</td><td>67</td><td>ASPK</td><td>+ 25-53 MeV e<sup>+</sup></td></tr><tr><td>0.05 ± 0.5</td><td>800k</td><td>4 PEOPLES</td><td>66</td><td>ASPK</td><td>+ 20-53 MeV e<sup>+</sup></td></tr><tr><td>-2.0 ± 0.9</td><td>9213</td><td>5 PLANO</td><td>60</td><td>HBC</td><td>+ Whole spectrum</td></tr></tbody></table>

1. Previously we used the global fit result from BURKARD 85b in OUR AVERAGE, we now only include their actual measurement.

2. $\alpha' = \alpha' = 0$ assumed.

3. Global fit to all measured parameters. The fit correlation coefficients are given in BURKARD 85b.

4. $\rho$ constrained = 0.75.

5. Two parameter fit to $\rho$ and $\eta$; PLANO 60 discounts value for $\eta$.

### δ PARAMETER

(V-A) theory predicts $\delta = 0.75$.

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>0.75047 ± 0.00034</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>0.75049 ± 0.00021 ± 0.00027</td><td></td><td>1 BAYES</td><td>11</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td>0.7486 ± 0.0026 ± 0.0028</td><td></td><td>2 BALKE</td><td>88</td><td>SPEC</td><td>+ Surface μ<sup>+</sup></td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>0.75067 ± 0.00030 ± 0.00067</td><td>MACDONALD</td><td>08</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td>0.74964 ± 0.00066 ± 0.00112</td><td>GAPONENKO</td><td>05</td><td>TWST</td><td>+ Surface μ<sup>+</sup></td></tr><tr><td></td><td><sup>3</sup> VOSSLER</td><td>69</td><td></td><td></td></tr></table>

<table><tr><td>0.752 ± 0.009</td><td>490k</td><td>FRYBERGER</td><td>68</td><td>ASPK</td><td>+ 25-53 MeV e<sup>+</sup></td></tr><tr><td>0.782 ± 0.031</td><td></td><td>KRUGER</td><td>61</td><td></td><td></td></tr><tr><td>0.78 ± 0.05</td><td>8354</td><td>PLANO</td><td>60</td><td>HBC</td><td>+ Whole spectrum</td></tr></table>

1. The quoted systematic error includes a contribution of 0.00006 (added in quadrature) from uncertainties on radiative corrections and on the Michel parameter $\eta$.

2. BALKE 88 uses $\rho = 0.752 \pm 0.003$.

3. VOSSLER 69 has measured the asymmetry below 10 MeV. See comments about radiative corrections in VOSSLER 69.

## [(ξ PARAMETER)×(μ LONGITUDINAL POLARIZATION)]

(V-A) theory predicts $\xi = 1$, longitudinal polarization = 1.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>1.0009 ± 0.0016</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td></tr><tr><td>1.00084 ± 0.00029 ± 0.00165</td><td>BUENO</td><td>11</td><td>TWST</td><td>+ Surface μ<sup>+</sup> beam</td></tr><tr><td>-0.00063</td><td></td><td></td><td></td><td></td></tr><tr><td>1.0027 ± 0.0079 ± 0.0030</td><td>BELTRAMI</td><td>87</td><td>CNTR</td><td>SIN, π decay in flight</td></tr><tr><td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td></tr><tr><td>1.0003 ± 0.0006 ± 0.0038</td><td>JAMIESON</td><td>06</td><td>TWST</td><td>+ surface μ<sup>+</sup> beam</td></tr><tr><td>1.0013 ± 0.0030 ± 0.0053</td><td>1 IMAZATO</td><td>92</td><td>SPEC</td><td>+ K<sup>+</sup> → μ<sup>+</sup>ν<sub>μ</sub></td></tr><tr><td>0.975 ± 0.015</td><td>AKHMANOV</td><td>68</td><td>EMUL</td><td>140 kG</td></tr><tr><td>0.975 ± 0.030</td><td>GUREVICH</td><td>64</td><td>EMUL</td><td>See AKHMANOV 68</td></tr><tr><td>0.903 ± 0.027</td><td>2 ALI-ZADE</td><td>61</td><td>EMUL</td><td>+ 27 kG</td></tr><tr><td>0.93 ± 0.06</td><td>PLANO</td><td>60</td><td>HBC</td><td>+ 8.8 kG</td></tr><tr><td>0.97 ± 0.05</td><td>BARDON</td><td>59</td><td>CNTR</td><td>Bromoform target</td></tr></tbody></table>

1. The corresponding 90% confidence limit from IMAZATO 92 is $|\xi P_{\mu}| > 0.990$. This measurement is of $K^+$ decay, not $\pi^+$ decay, so we do not include it in an average, nor do we yet set up a separate data block for $K$ results.

2. Depolarization by medium not known sufficiently well.

## ξ × (μ LONGITUDINAL POLARIZATION) × δ / ρ

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>1.00179 ± 0.00156</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>0.99682</td><td>90</td><td>2 JODIDIO</td><td>86</td><td>SPEC</td><td>+ TRIUMF</td></tr><tr><td>0.9966</td><td>90</td><td>3 STOKER</td><td>85</td><td>SPEC</td><td>+ μ-spin rotation</td></tr><tr><td>0.9959</td><td>90</td><td>CARR</td><td>83</td><td>SPEC</td><td>+ 11 kG</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>>0.99682</td><td>90</td><td>2 JODIDIO</td><td>86</td><td>SPEC</td><td>+ TRIUMF</td></tr><tr><td>>0.9966</td><td>90</td><td>3 STOKER</td><td>85</td><td>SPEC</td><td>+ μ-spin rotation</td></tr><tr><td>>0.9959</td><td>90</td><td>CARR</td><td>83</td><td>SPEC</td><td>+ 11 kG</td></tr></table>

1. BAYES 11 obtains the limit > 0.99909 (90% CL) with the constraint that $\xi \times (\mu \text{ LONGITUDINAL POLARIZATION}) \times \delta/\rho \le 1.0$.

2. JODIDIO 86 includes data from CARR 83 and STOKER 85. The value here is from the erratum.

3. STOKER 85 find $(\xi P_{\mu} \delta/\rho) > 0.99955$ and $>0.99966$, where the first limit is from new $\mu$ spin-rotation data and the second is from combination with CARR 83 data. In V-A theory, $(\delta/\rho) = 1.0$.

## ξ' = LONGITUDINAL POLARIZATION OF e<sup>+</sup>

(V-A) theory predicts the longitudinal polarization = $\pm 1$ for $e^{\pm}$, respectively. We have flipped the sign for $e^-$ so our programs can average.

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>1.00 ± 0.04</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>0.998 ± 0.045</td><td>1M</td><td>BURKARD</td><td>85</td><td>CNTR</td><td>+ Bhabha + annihil</td></tr><tr><td>0.89 ± 0.28</td><td>29k</td><td>SCHWARTZ</td><td>67</td><td>OSPK</td><td>- Moller scattering</td></tr><tr><td>0.94 ± 0.38</td><td></td><td>BLOOM</td><td>64</td><td>CNTR</td><td>+ Brems. transmiss.</td></tr><tr><td>1.04 ± 0.18</td><td></td><td>DUCLOS</td><td>64</td><td>CNTR</td><td>+ Bhabha scattering</td></tr><tr><td>1.05 ± 0.30</td><td></td><td>BUHLER</td><td>63</td><td>CNTR</td><td>+ Annihilation</td></tr></tbody></table>

## ξ'' PARAMETER

<table><thead><tr><th>VALUE</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>0.98 ± 0.04</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>0.981 ± 0.045 ± 0.003</td><td>3.87M</td><td>PRIEELS</td><td>14</td><td>CNTR</td><td>+ Bhabha + annihil</td></tr><tr><td>0.65 ± 0.36</td><td>326k</td><td>1 BURKARD</td><td>85</td><td>CNTR</td><td>+ Bhabha + annihil</td></tr></tbody></table>

1. BURKARD 85 measure $(\xi'' - \xi\xi')/\xi$ and $\xi'$ and set $\xi = 1$.

## TRANSVERSE e<sup>+</sup> POLARIZATION IN PLANE OF μ SPIN, e<sup>+</sup> MOMENTUM

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>7 ± 8</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>6.3 ± 7.7 ± 3.4</td><td>30M</td><td>DANNEBERG</td><td>05</td><td>CNTR</td><td>+ 7-53 MeV e<sup>+</sup></td></tr><tr><td>16 ± 21 ± 10</td><td>5.3M</td><td>BURKARD</td><td>85b</td><td>CNTR</td><td>+ Annihil 9-53 MeV</td></tr></tbody></table>

## TRANSVERSE e<sup>+</sup> POLARIZATION NORMAL TO PLANE OF μ SPIN, e<sup>+</sup> MOMENTUM

Zero if T invariance holds.

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td><strong>-2 ± 8</strong></td><td><strong>OUR AVERAGE</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>-3.7 ± 7.7 ± 3.4</td><td>30M</td><td>DANNEBERG</td><td>05</td><td>CNTR</td><td>+ 7-53 MeV e<sup>+</sup></td></tr><tr><td>7 ± 22 ± 7</td><td>5.3M</td><td>BURKARD</td><td>85b</td><td>CNTR</td><td>+ Annihil 9-53 MeV</td></tr></tbody></table>
### α/A

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>0.4 ± 4.3</td><td></td><td>1 BURKARD</td><td>85B</td><td>FIT</td><td></td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>15 ± 50 ± 14</td><td>5.3M</td><td>BURKARD</td><td>85B</td><td>CNTR +</td><td>9–53 MeV e<sup>+</sup></td></tr></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### α'/A

Zero if T invariance holds.

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>-10 ± 20</td><td>OUR AVERAGE</td><td></td><td></td><td></td><td></td></tr></tbody></table>

<table><tr><td>– 3.4 ± 21.3 ± 4.9</td><td>30M</td><td>DANNEBERG</td><td>05</td><td>CNTR +</td><td>7–53 MeV e<sup>+</sup></td></tr></table>

<table><tr><td>– 47 ± 50 ± 14</td><td>5.3M</td><td>1 BURKARD</td><td>85B</td><td>CNTR +</td><td>9–53 MeV e<sup>+</sup></td></tr></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>– 0.2 ± 4.3</td><td>2 BURKARD</td><td>85B</td><td>FIT</td><td></td><td></td></tr></table>

¹Previously we used the global fit result from BURKARD 85B in OUR AVERAGE, we now only include their actual measurement. BURKARD 85B measure e⁺ polarizations P<sub>T<sub>1</sub></sub> and P<sub>T<sub>2</sub></sub> versus e⁺ energy.

²Global fit to all measured parameters. The fit correlation coefficients are given in BURKARD 85B.

### β/A

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>3.9 ± 6.2</td><td></td><td>1 BURKARD</td><td>85B</td><td>FIT</td><td></td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>2 ± 17 ± 6</td><td>5.3M</td><td>BURKARD</td><td>85B</td><td>CNTR +</td><td>9–53 MeV e<sup>+</sup></td></tr></table>

¹Global fit to all measured parameters. The fit correlation coefficients are given in BURKARD 85B.

### β'/A

Zero if T invariance holds.

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>EVTS</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>2 ± 7</td><td>OUR AVERAGE</td><td></td><td></td><td></td><td></td></tr></tbody></table>

<table><tr><td>– 0.5 ± 7.8 ± 1.8</td><td>30M</td><td>DANNEBERG</td><td>05</td><td>CNTR +</td><td>7–53 MeV e<sup>+</sup></td></tr></table>

<table><tr><td>17 ± 17 ± 6</td><td>5.3M</td><td>1 BURKARD</td><td>85B</td><td>CNTR +</td><td>9–53 MeV e<sup>+</sup></td></tr></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>– 1.3 ± 3.5 ± 0.6</td><td>30M</td><td>2 DANNEBERG</td><td>05</td><td>CNTR +</td><td>7–53 MeV e<sup>+</sup></td></tr><tr><td>1.5 ± 6.3</td><td>3 BURKARD</td><td>85B</td><td>FIT</td><td></td><td></td></tr></table>

¹Previously we used the global fit result from BURKARD 85B in OUR AVERAGE, we now only include their actual measurement. BURKARD 85B measure e⁺ polarizations P<sub>T<sub>1</sub></sub> and P<sub>T<sub>2</sub></sub> versus e⁺ energy.

²α = α' = 0 assumed.

³Global fit to all measured parameters. The fit correlation coefficients are given in BURKARD 85B.

### α/A

This comes from an alternative parameterization to that used in the Summary Table (see the "Note on Muon Decay Parameters" above).

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th></tr></thead><tbody><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>&lt;15.9</td><td>90</td><td>1 BURKARD</td><td>85B</td><td>FIT</td></tr></tbody></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### d/A

This comes from an alternative parameterization to that used in the Summary Table (see the "Note on Muon Decay Parameters" above).

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>DOCUMENT ID</th><th>TECN</th></tr></thead><tbody><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td></tr></tbody></table>

<table><tr><td>5.3 ± 4.1</td><td>1 BURKARD</td><td>85B</td><td>FIT</td><td></td><td></td></tr></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### (b'+b)/A

This comes from an alternative parameterization to that used in the Summary Table (see the "Note on Muon Decay Parameters" above).

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th></tr></thead><tbody><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>&lt;1.04</td><td>90</td><td>1 BURKARD</td><td>85B</td><td>FIT</td></tr></tbody></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### c/A

This comes from an alternative parameterization to that used in the Summary Table (see the "Note on Muon Decay Parameters" above).

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th></tr></thead><tbody><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td><td></td></tr><tr><td>&lt;6.4</td><td>90</td><td>1 BURKARD</td><td>85B</td><td>FIT</td></tr></tbody></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### c'/A

This comes from an alternative parameterization to that used in the Summary Table (see the "Note on Muon Decay Parameters" above).

<table><thead><tr><th>VALUE (units 10<sup>-3</sup>)</th><th>DOCUMENT ID</th><th>TECN</th></tr></thead><tbody><tr><td>• • • We do not use the following data for averages, fits, limits, etc. • • •</td><td></td><td></td></tr><tr><td>3.5 ± 2.0</td><td>1 BURKARD</td><td>85B</td><td>FIT</td><td></td></tr></tbody></table>

¹Global fit to all measured parameters. Correlation coefficients are given in BURKARD 85B.

### η PARAMETER

(V-A) theory predicts η = 0. η affects spectrum of radiative muon decay.

<table><thead><tr><th>VALUE</th><th>DOCUMENT ID</th><th>TECN</th><th>CHG</th><th>COMMENT</th></tr></thead><tbody><tr><td>0.02 ± 0.08</td><td>OUR AVERAGE</td><td></td><td></td><td></td></tr><tr><td>-0.014 ± 0.090</td><td></td><td>EICHENBER...</td><td>84</td><td>ELEC + ρ free</td></tr><tr><td>+0.09 ± 0.14</td><td></td><td>BOGART</td><td>67</td><td>CNTR +</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tr><td>-0.035 ± 0.098</td><td>EICHENBER...</td><td>84</td><td>ELEC +</td><td>ρ=0.75 assumed</td></tr></table>

### μ REFERENCES

<table><tr><td>AGUILLARD</td><td>23</td><td>PRL 131 161802</td><td>D.P. Aguillard et al.</td><td>(Muon g-2 Collab.)</td></tr><tr><td>EMA</td><td>22</td><td>PRL 128 131803</td><td>Y. Ema, T. Gao, M. Pospelov</td><td>(DESY, MINN)</td></tr><tr><td>ABI</td><td>21</td><td>PRL 126 148101</td><td>B. Abi et al.</td><td>(Muon g-2 Collab.)</td></tr><tr><td>TIESINGA</td><td>21</td><td>RMP 93 025010</td><td>E. Tiesinga et al.</td><td>(NIST)</td></tr><tr><td>AOYAMA</td><td>20</td><td>PRPL 887 1</td><td>T. Aoyama et al.</td><td></td></tr><tr><td>BALDINI</td><td>20</td><td>EJ.P C80 858</td><td>A.M. Baldini et al.</td><td>(MEG Collab.)</td></tr><tr><td>BALDINI</td><td>16</td><td>EJ.P C76 434</td><td>A.M. Baldini et al.</td><td>(MEG Collab.)</td></tr><tr><td>BALDINI</td><td>16A</td><td>EJ.P C76 108</td><td>A.M. Baldini et al.</td><td>(MEG Collab.)</td></tr><tr><td>MOHR</td><td>16</td><td>RMP 88 035009</td><td>P.J. Mohr, D.B. Newell, B.N. Taylor</td><td>(NIST)</td></tr><tr><td>PRIEDS</td><td>14</td><td>PR D90 112003</td><td>R. Priedd et al.</td><td>(LOUV, ETH PSI+)</td></tr><tr><td>ADAM</td><td>13B</td><td>PRL 110 201801</td><td>J. Adam et al.</td><td>(MEG Collab.)</td></tr><tr><td>TISHENKHO</td><td>13</td><td>PR D87 052003</td><td>V. Tishchenko et al.</td><td>(MuLan Collab.)</td></tr><tr><td>MOHR</td><td>12</td><td>RMP 84 1527</td><td>P.J. Mohr, B.N. Taylor, D.B. Newell</td><td>(NIST)</td></tr><tr><td>ADAM</td><td>11</td><td>PRL 107 171801</td><td>J. Adam et al.</td><td>(MEG Collab.)</td></tr><tr><td>BAYES</td><td>11</td><td>PR 106 041804</td><td>R. Bayes et al.</td><td>(TWIST Collab.)</td></tr><tr><td>Also</td><td>11</td><td>PR D85 092013</td><td>A. Hillairet et al.</td><td>(TWIST Collab.)</td></tr><tr><td>BUENO</td><td>11</td><td>PR D84 032005</td><td>J.F. Bueno et al.</td><td>(TWIST Collab.)</td></tr><tr><td>Also</td><td>11</td><td>PR D85 039908 (errat.)</td><td>J.F. Bueno et al.</td><td>(TWIST Collab.)</td></tr><tr><td>WEBBER</td><td>11</td><td>PRL 106 041803</td><td>D.M. Webber et al.</td><td>(MuLan Collab.)</td></tr><tr><td>Also</td><td>10</td><td>PRL 106 079901 (errat.)</td><td>D.M. Webber et al.</td><td>(MuLan Collab.)</td></tr><tr><td>ADAM</td><td>10</td><td>NP B834 1</td><td>J. Adam et al.</td><td>(MEG Collab.)</td></tr><tr><td>BENNETT</td><td>09</td><td>PR D80 052008</td><td>G.W. Bennett et al.</td><td>(MUG-2 Collab.)</td></tr><tr><td>BARCZYK</td><td>08</td><td>NP B663 172</td><td>A. Barczyk et al.</td><td>(FAST Collab.)</td></tr><tr><td>MACDONALD</td><td>08</td><td>PR D78 032010</td><td>R.P. MacDonald et al.</td><td>(TWIST Collab.)</td></tr><tr><td>MOHR</td><td>08</td><td>RMP 80 633</td><td>P.J. Mohr, B.N. Taylor, D.B. Newell</td><td>(NIST)</td></tr><tr><td>CHITWOOD</td><td>07</td><td>PR D79 032001</td><td>D.B. Chitwood et al.</td><td>(MUlan Collab.)</td></tr><tr><td>BENNETT</td><td>06</td><td>PR D73 072003</td><td>G.W. Bennett et al.</td><td>(MUG-2 Collab.)</td></tr><tr><td>BERTL</td><td>06</td><td>EJ.P C47 337</td><td>W. Bertl et al.</td><td>(SINDRUM II Collab.)</td></tr><tr><td>JAMESON</td><td>06</td><td>PR D74 027002</td><td>B. Jamieson et al.</td><td>(TWIST Collab.)</td></tr><tr><td>DANNEBERG</td><td>05</td><td>PR 94 021802</td><td>N. Danneberg et al.</td><td>(ETH, JAGL, PSI+)</td></tr><tr><td>GAPONENKO</td><td>05</td><td>PR D71 071101</td><td>A. Gaponenko et al.</td><td>(TWIST Collab.)</td></tr><tr><td>MOHR</td><td>05</td><td>RMP 77 1</td><td>P.J. Mohr, B.N. Taylor</td><td>(NIST)</td></tr><tr><td>MUSSER</td><td>05</td><td>PR 94 101805</td><td>J.R. Musser et al.</td><td>(TWIST Collab.)</td></tr><tr><td>AMORUSO</td><td>04</td><td>EJ.P C33 233</td><td>S. Amoruso et al.</td><td>(ICARUS Collab.)</td></tr><tr><td>BENNETT</td><td>04</td><td>PR 92 161802</td><td>G.W. Bennett et al.</td><td>(Muon(g-2) Collab.)</td></tr><tr><td>AHMED</td><td>02</td><td>PR D65 112002</td><td>M. Ahmed et al.</td><td>(MEGA Collab.)</td></tr><tr><td>BENNETT</td><td>02</td><td>PR 89 101804</td><td>G.W. Bennett et al.</td><td>(Muon(g-2) Collab.)</td></tr><tr><td>BROWN</td><td>01</td><td>PR 86 2227</td><td>H.N. Brown et al.</td><td>(Muon(g-2) Collab.)</td></tr><tr><td>BROWN</td><td>00</td><td>PR D62 091101</td><td>H.N. Brown et al.</td><td>(BNL/G-2 Collab.)</td></tr><tr><td>Meyer</td><td>00</td><td>PR 84 1136</td><td>V. Meyer et al.</td><td></td></tr><tr><td>BROOKS</td><td>99</td><td>PR 83 1521</td><td>M.L. Brooks et al.</td><td>(MEGA/LAMPF Collab.)</td></tr><tr><td>HUGHES</td><td>99</td><td>RMP 71 5133</td><td>V.W. Hughes, T. Kinoshita</td><td></td></tr><tr><td>LIU</td><td>99</td><td>PR 82 711</td><td>W. Liu et al.</td><td>(LAMPF Collab.)</td></tr><tr><td>MOHR</td><td>99</td><td>JPCRD 28 1713</td><td>P.J. Mohr, B.N. Taylor</td><td>(NIST)</td></tr><tr><td>Also</td><td>99</td><td>PRL 82 49</td><td>P.J. Mohr, B.N. Taylor</td><td>(NIST)</td></tr><tr><td>WILLMANN</td><td>99</td><td>PR D57 3873</td><td>L. Willmann et al.</td><td></td></tr><tr><td>FELDMAN</td><td>98</td><td>PR D22 334</td><td>G.J. Feldman, R.D. Cousins</td><td></td></tr><tr><td>KAUER</td><td>97</td><td>PAN 60 1164</td><td>J. Kaulard et al.</td><td>(SINDRUM-II Collab.)</td></tr><tr><td>GORDEEV</td><td>97</td><td>TRANSLATED FROM YAF 60 1291.</td><td>V.A. Gordeev et al.</td><td>(PNPI)</td></tr><tr><td>ABELA</td><td>96</td><td>PRL 77 1950</td><td>R. Abela et al.</td><td>(PSI, ZURI, HEIDH, TBIL+)</td></tr><tr><td>HONECKER</td><td>96</td><td>PRL 76 200</td><td>W. Honecker et al.</td><td>(SINDRUM II Collab.)</td></tr><tr><td>DOHMEN</td><td>93</td><td>PR B317 631</td><td>C. Dohmen et al.</td><td>(PSI SINDRUM-II Collab.)</td></tr><tr><td>FREEEDMAN</td><td>93</td><td>PR D47 811</td><td>S.J. Freedman et al.</td><td>(LAMPF E645 Collab.)</td></tr><tr><td>NI</td><td>93</td><td>PR D48 1976</td><td>B. Ni et al.</td><td>(LAMPF Crystal-Box Collab.)</td></tr><tr><td>IMAZATO</td><td>92</td><td>PR 69 877</td><td>J. Imazato et al.</td><td>(KEK, INUS, TOKY+)</td></tr><tr><td>SJNP</td><td>91</td><td>SJNP 53 802</td><td>V.A. Baranov et al.</td><td>(JINR)</td></tr><tr><td>GORANOV</td><td>92</td><td>PR 69 877</td><td>V.A. Baranov et al.</td><td></td></tr><tr><td>TRIATED FROM YAF 53 1302.</td><td>91B</td><td>PL B263 534</td><td>D.A. Kraukauer et al.</td><td>(UMD, UCI, LANL)</td></tr><tr><td>KRAKAUER</td><td>91B</td><td>PL B263 534</td><td>B.E. Matthias et al.</td><td>(YALE, HEIDP, WILL+)</td></tr><tr><td>MATTHIAS</td><td>91</td><td>PL 66 2716</td><td>B.E. Matthias et al.</td><td>(YALE, HEIDP, WILL+)</td></tr><tr><td>Also</td><td>90B</td><td>PR D41 2709</td><td>T.M. Huber et al.</td><td>(WYOM, VICT, ARIZ+)</td></tr><tr><td>HUBER</td><td>88</td><td>PR D38 2120</td><td>S. Ahmad et al.</td><td>(TRIU, VICT, VPI, BRCO+)</td></tr><tr><td>Also</td><td>88</td><td>PR D38 2120</td><td>S. Ahmad et al.</td><td>(TRIU, VPI, VICT, BRCO+)</td></tr><tr><td>BALKE</td><td>88</td><td>PR D37 587</td><td>B. Balke et al.</td><td>(LBL, UCB, COLO, NWES+)</td></tr><tr><td>BELLGARDT</td><td>88</td><td>NP B299 1</td><td>U. Bellgardt et al.</td><td>(SINDRUM Collab.)</td></tr><tr><td>BOLTON</td><td>88</td><td>PR D38 2077</td><td>R.D. Bolton et al.</td><td>(LANL, STAN, CHIC+)</td></tr><tr><td>Also</td><td>88</td><td>PR 56 2461</td><td>R.D. Bolton et al.</td><td>(LANL, STAN, CHIC+)</td></tr><tr><td>Also</td><td>88</td><td>PR 57 3241</td><td>D. Grosnick et al.</td><td>(CHIC, LANL, STAN+)</td></tr><tr><td>BELTRAMI</td><td>87</td><td>PR B194 326</td><td>I. Beltrami et al.</td><td>(ETH, SIN, MAINZ)</td></tr><tr><td>COHEN</td><td>87</td><td>RMP 59 1121</td><td>E.R. Cohen, B.N. Taylor</td><td>(RISC, NBS)</td></tr><tr><td>BEER</td><td>86</td><td>PR 57 671</td><td>G.A. Beer et al.</td><td>(VICT, TRIU, WYOM)</td></tr><tr><td>JODISNO</td><td>86</td><td>PR 57 1967</td><td>A. Jodidio et al.</td><td>(LBL, NWES, TRIU)</td></tr><tr><td>Also</td><td>86</td><td>PR D37 237 (errat.)</td><td>A. Jodidio et al.</td><td>(SINDRUM Collab.)</td></tr><tr><td>BERTL</td><td>85</td><td>NP B260 1</td><td>W. Berti et al.</td><td>(TRIU, CNRC, BRCO+)</td></tr><tr><td>BRYMAN</td><td>85</td><td>PRL 55 465</td><td>D.A. Bryan et al.</td><td>(ETH, SIN, MAINZ)</td></tr><tr><td>BURKARD</td><td>85</td><td>PL 150B 242</td><td>H. Burkhardt et al.</td><td>(ETH, SIN, MAINZ)</td></tr><tr><td>BURKARD</td><td>85B</td><td>PL D204 343</td><td>F. Corriveau et al.</td><td>(ETH, SIN, MAINZ)</td></tr><tr><td>Also</td><td>85</td><td>PL D204 2004</td><td>F. Corriveau et al.</td><td>(ETH, SIN, MAINZ)</td></tr><tr><td>Also</td><td>85</td><td>PL 129B 260</td><td>D.P. Stoker et al.</td><td>(LBL, NWES, TRIU)</td></tr><tr><td>STOKER</td><td>85</td><td>PRL 54 1887</td><td>G. Bardin et al.</td><td>(SACL, CERN, BGNA, FIRZ)</td></tr><tr><td>BARDIN</td><td>84</td><td>PL 137B 135</td><td>W. Bertl et al.</td><td>(SINDRUM Collab.)</td></tr><tr><td>BERTL</td><td>84</td><td>PL 140B 299</td><td>R.D. Bolton et al.</td><td>(LANL, CHIC, STAN+)</td></tr><tr><td>BOLTON</td><td>84</td><td>PR 53 1415</td><td>W. Eichenberger, R. Engfer, A. van der Schaff</td><td></td></tr><tr><td>EICHENBER...</td><td>84</td><td>NP A412 523</td><td>K.L. Giovanetti et al.</td><td>(WILL)</td></tr><tr><td>GIOVANETTI</td><td>84</td><td>PR D29 343</td><td>G. Azuelos et al.</td><td>(MONT, TRIU, BRCO)</td></tr><tr><td>AZUELOS</td><td>83</td><td>PR 51 164</td><td>P. Depommier et al.</td><td>(MONT, BRCO, TRIU+)</td></tr><tr><td>Also</td><td>83</td><td>PRL 39 1113</td><td>F. Bergsma et al.</td><td>(CHARM Collab.)</td></tr><tr><td>BERGSMA</td><td>83</td><td>PL 122B 465</td><td>J. Carr et al.</td><td>(LBL, NWES, TRIU)</td></tr><tr><td>CARR</td><td>83</td><td>PRL 51 627</td><td>W.W. Kinnison et al.</td><td>(EFI, STAN, LANL)</td></tr><tr><td>KINNISON</td><td>82</td><td>PR D25 2846</td><td>J.D. Bowman et al.</td><td>(LASL, EFI, STAN)</td></tr><tr><td>Also</td><td>82</td><td>PRL 42 556</td><td></td><td></td></tr></table>
See key on page 1171

Lepton Particle Listings

μ, τ

<table>
  <tbody>
    <tr>
      <td>KLEMPT</td>
      <td>82</td>
      <td>PR D25 652</td>
      <td>E. Klempt et al.</td>
      <td>(MAINZ, ETH)</td>
    </tr>
    <tr>
      <td>MARIAM</td>
      <td>82</td>
      <td>PRL 49 993</td>
      <td>F.G. Mariam et al.</td>
      <td>(YALE, HEIDH, BERN)</td>
    </tr>
    <tr>
      <td>MARSHALL</td>
      <td>82</td>
      <td>PR D25 1174</td>
      <td>G.M. Marshall et al.</td>
      <td>(BRCO)</td>
    </tr>
    <tr>
      <td>NEMETH</td>
      <td>81</td>
      <td>CNPQ 10 147</td>
      <td>P. Nemethy, V.W. Hughes</td>
      <td>(LBL, YALE)</td>
    </tr>
    <tr>
      <td>ABELA</td>
      <td>80</td>
      <td>PL 95B 318</td>
      <td>R. Abela et al.</td>
      <td>(BASL, KARLK, KARLE)</td>
    </tr>
    <tr>
      <td>BADERT...</td>
      <td>80</td>
      <td>LNC 28 401</td>
      <td>A. Badertscher et al.</td>
      <td>(BERN)</td>
    </tr>
    <tr>
      <td>Also</td>
      <td></td>
      <td>NP A377 406</td>
      <td>A. Badertscher et al.</td>
      <td>(BERN)</td>
    </tr>
    <tr>
      <td>JONKER</td>
      <td>80</td>
      <td>PL 93B 203</td>
      <td>M. Jonker et al.</td>
      <td>(CHARM Collab.)</td>
    </tr>
    <tr>
      <td>SCHAAF</td>
      <td>80</td>
      <td>NP A340 249</td>
      <td>A. van der SchAAF et al.</td>
      <td>(ZURI, ETH+)</td>
    </tr>
    <tr>
      <td>Also</td>
      <td></td>
      <td>PL 72B 183</td>
      <td>H.P. Povel et al.</td>
      <td>(ZURI, ETH, SIN)</td>
    </tr>
    <tr>
      <td>WILLIS</td>
      <td>80</td>
      <td>PRL 44 522</td>
      <td>S.E. Willis et al.</td>
      <td>(YALE, LBL, LASL+)</td>
    </tr>
    <tr>
      <td>Also</td>
      <td></td>
      <td>PRL 45 1370</td>
      <td>S.E. Willis et al.</td>
      <td>(YALE, LBL, LASL+)</td>
    </tr>
    <tr>
      <td>BAILEY</td>
      <td>79</td>
      <td>NP B150 1</td>
      <td>J.M. Bailey</td>
      <td>(CERN, DARE, MAINZ)</td>
    </tr>
    <tr>
      <td>BADERT...</td>
      <td>78</td>
      <td>PL 79B 371</td>
      <td>A. Badertscher et al.</td>
      <td>(BERN)</td>
    </tr>
    <tr>
      <td>BAILEY</td>
      <td>78</td>
      <td>JP G4 345</td>
      <td>J.M. Bailey (DARE, BERN, SHEF, MAINZ, RMCS+)</td>
      <td>(CERN, DARE, MAINZ)</td>
    </tr>
    <tr>
      <td>Also</td>
      <td></td>
      <td>NP B150 1</td>
      <td>J.M. Bailey</td>
      <td>(Gargamelle Collab.)</td>
    </tr>
    <tr>
      <td>BULETSCHAU</td>
      <td>78</td>
      <td>NP B133 205</td>
      <td>J. Blietschau et al.</td>
      <td>(LASL, IAS, CMU+)</td>
    </tr>
    <tr>
      <td>BOWMAN</td>
      <td>78</td>
      <td>NP B141 442</td>
      <td>J.D. Bowman et al.</td>
      <td>(ETH, MAINZ)</td>
    </tr>
    <tr>
      <td>CAMANI</td>
      <td>78</td>
      <td>PL 77B 326</td>
      <td>M. Camani et al.</td>
      <td>(BERN)</td>
    </tr>
    <tr>
      <td>BADERT...</td>
      <td>77</td>
      <td>PRL 39 1385</td>
      <td>A. Badertscher et al.</td>
      <td>(BERN)</td>
    </tr>
    <tr>
      <td>CASPERSON</td>
      <td>77</td>
      <td>PRL 38 956</td>
      <td>D.E. Casperson et al.</td>
      <td>(BERN, HEIDH, LASL+)</td>
    </tr>
    <tr>
      <td>DEPMOMIER</td>
      <td>77</td>
      <td>PRL 39 1113</td>
      <td>P. Depmommier et al.</td>
      <td>(MONT, BRCO, TRIU+)</td>
    </tr>
    <tr>
      <td>BALANDIN</td>
      <td>77</td>
      <td>JETP 40 811</td>
      <td>M.P. Balandin et al.</td>
      <td>(JINR)</td>
    </tr>
    <tr>
      <td></td>
      <td></td>
      <td>Translated from ZETF 67 1631.</td>
      <td></td>
      <td></td>
    </tr>
    <tr>
      <td>COHEN</td>
      <td>73</td>
      <td>JPCRD 2 664</td>
      <td>E.R. Cohen, B.N. Taylor</td>
      <td>(RISC, NBS)</td>
    </tr>
    <tr>
      <td>DUCLOS</td>
      <td>73</td>
      <td>PL 47B 491</td>
      <td>J. Duclos, A. Magnon, J. Picard</td>
      <td>(SACL)</td>
    </tr>
    <tr>
      <td>EICHEN</td>
      <td>73</td>
      <td>PL 46B 281</td>
      <td>T. Eichen et al.</td>
      <td>(Gargamelle Collab.)</td>
    </tr>
    <tr>
      <td>BRYMAN</td>
      <td>72</td>
      <td>PL 28 1469</td>
      <td>D.A. Bryman et al.</td>
      <td>(VPi)</td>
    </tr>
    <tr>
      <td>CROWE</td>
      <td>72</td>
      <td>PR D5 2145</td>
      <td>K.M. Crowe et al.</td>
      <td>(LBL, WASH)</td>
    </tr>
    <tr>
      <td>CRANE</td>
      <td>71</td>
      <td>PRL 27 474</td>
      <td>T. Crane et al.</td>
      <td>(YALE)</td>
    </tr>
    <tr>
      <td>DERENZO</td>
      <td>69</td>
      <td>PR 181 1854</td>
      <td>S.E. Derenz</td>
      <td>(EFI)</td>
    </tr>
    <tr>
      <td>VOSSLER</td>
      <td>69</td>
      <td>NC 63A 423</td>
      <td>C. Vossler</td>
      <td>(EFI)</td>
    </tr>
    <tr>
      <td>AKHMANOV</td>
      <td>68</td>
      <td>SJPN 6 230</td>
      <td>V.V. Akhmanov et al.</td>
      <td>(KIAE)</td>
    </tr>
    <tr>
      <td></td>
      <td></td>
      <td>Translated from YAF 6 316.</td>
      <td></td>
      <td></td>
    </tr>
    <tr>
      <td>FRYBERGER</td>
      <td>68</td>
      <td>PR 166 1379</td>
      <td>D. Fryberger</td>
      <td>(EFI)</td>
    </tr>
    <tr>
      <td>BOGART</td>
      <td>67</td>
      <td>PR 156 1405</td>
      <td>E. Bogart et al.</td>
      <td>(COLU)</td>
    </tr>
    <tr>
      <td>SCHWARTZ</td>
      <td>67</td>
      <td>PR 152 1306</td>
      <td>D.M. Schwartz</td>
      <td>(EFI)</td>
    </tr>
    <tr>
      <td>SHERWOOD</td>
      <td>67</td>
      <td>PR 156 1475</td>
      <td>B.A. Sherwood</td>
      <td>(EFI)</td>
    </tr>
    <tr>
      <td>PEOPLES</td>
      <td>66</td>
      <td>Nevis 147 unpub.</td>
      <td>J. Peoples</td>
      <td>(COLU)</td>
    </tr>
    <tr>
      <td>BLOOM</td>
      <td>64</td>
      <td>PL 8 87</td>
      <td>S. Bloom et al.</td>
      <td>(CERN)</td>
    </tr>
    <tr>
      <td>DUCLOS</td>
      <td>64</td>
      <td>PL 9 62</td>
      <td>J. Duclos et al.</td>
      <td>(CERN)</td>
    </tr>
    <tr>
      <td>GUREVICH</td>
      <td>64</td>
      <td>PL 11 185</td>
      <td>I.I. Gurevich et al.</td>
      <td>(KIAE)</td>
    </tr>
    <tr>
      <td>BUHLER</td>
      <td>63</td>
      <td>PL 368</td>
      <td>A. Buhrer-Broglin et al.</td>
      <td>(CERN)</td>
    </tr>
    <tr>
      <td>MEYER</td>
      <td>63</td>
      <td>PR 132 2693</td>
      <td>S.L. Meyer et al.</td>
      <td>(COLU)</td>
    </tr>
    <tr>
      <td>CHARPAK</td>
      <td>62</td>
      <td>PL 1 16</td>
      <td>G. Charpak et al.</td>
      <td>(COLU)</td>
    </tr>
    <tr>
      <td>CONFORTO</td>
      <td>62</td>
      <td>NC 26 261</td>
      <td>G. Conforto et al.</td>
      <td>(INFN, ROMA, CERN)</td>
    </tr>
    <tr>
      <td>ALI-ZADE</td>
      <td>61</td>
      <td>JETP 13 313</td>
      <td>S.A. Al-Zade, I.I. Gurevich, B.A. Nikolsky</td>
      <td></td>
    </tr>
    <tr>
      <td>CRITTENDEN</td>
      <td>61</td>
      <td>PR 121 1823</td>
      <td>R.R. Crittenden, W.D. Walker, J. Ballam</td>
      <td>(WISC+)</td>
    </tr>
    <tr>
      <td>KRUGER</td>
      <td>61</td>
      <td>UCRL 9322 unpub.</td>
      <td>H. Kruger</td>
      <td>(LRL)</td>
    </tr>
    <tr>
      <td>GUREVICH</td>
      <td>60</td>
      <td>JETP 10 225</td>
      <td>I.I. Gurevich, B.A. Nikolsky, L.V. Surkova</td>
      <td>(ITEP)</td>
    </tr>
    <tr>
      <td>PLANO</td>
      <td>60</td>
      <td>PR 119 1400</td>
      <td>R.J. Plano</td>
      <td>(COLU)</td>
    </tr>
    <tr>
      <td>ASHKIN</td>
      <td>59</td>
      <td>NC 14 1266</td>
      <td>J. Ashkin et al.</td>
      <td>(CERN)</td>
    </tr>
    <tr>
      <td>BARDON</td>
      <td>59</td>
      <td>PRL 2 56</td>
      <td>M. Bardon, D. Berley, L.M. Lederman</td>
      <td>(CERN)</td>
    </tr>
    <tr>
      <td>LEE</td>
      <td>59</td>
      <td>PRL 3 55</td>
      <td>J. Lee, N.P. Samios</td>
      <td>(COLU)</td>
    </tr>
  </tbody>
</table>

<figure><img src="image_409.png" /></figure>

$J = \frac{1}{2}$

τ discovery paper was PERL 75. $e^+e^- \to \tau^+\tau^-$ cross-section threshold behavior and magnitude are consistent with pointlike spin-1/2 Dirac particle. BRANDELIK 78 ruled out pointlike spin-0 or spin-1 particle. FELDMAN 78 ruled out $J=3/2$. KIRKBY 79 also ruled out $J=\text{integer}, J=3/2$.

τ MASS

<table>
  <thead>
    <tr>
      <th>VALUE (MeV)</th>
      <th>EVTS</th>
      <th>DOCUMENT ID</th>
      <th>TECN</th>
      <th>COMMENT</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td colspan="5"><strong>1776.93±0.09 OUR AVERAGE</strong></td>
    </tr>
    <tr>
      <td>1777.09±0.08±0.11</td>
      <td>175M</td>
      <td>1 ADACHI</td>
      <td>23C BELL</td>
      <td>190 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>1776.69<sup>+0.17</sup><sub>-0.19</sub>±0.15</td>
      <td></td>
      <td>2 ANASHIN</td>
      <td>23A KEDR</td>
      <td>(6.7+8.5) pb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 3.54-3.78 GeV</td>
    </tr>
    <tr>
      <td>1776.91±0.12<sup>+0.10</sup><sub>-0.13</sub></td>
      <td>1171</td>
      <td>3 ABLIKIM</td>
      <td>14D BES3</td>
      <td>23.3 pb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 3.54-3.60 GeV</td>
    </tr>
    <tr>
      <td>1776.68±0.12±0.41</td>
      <td>682k</td>
      <td>1 AUBERT</td>
      <td>09AK BABR</td>
      <td>423 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>1776.61±0.13±0.35</td>
      <td></td>
      <td>1 BELOUS</td>
      <td>07 BELL</td>
      <td>414 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>1775.1±1.6±1.0</td>
      <td>13.3k</td>
      <td>4 ABBIENDI</td>
      <td>00A OPAL</td>
      <td>1990-1995 LEP runs</td>
    </tr>
    <tr>
      <td>1778.2±0.8±1.2</td>
      <td></td>
      <td>ANASTASSOV</td>
      <td>97 CLEO</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>1776.96<sup>+0.18</sup><sub>-0.21</sub>±0.15</td>
      <td>65</td>
      <td>5 BAI</td>
      <td>96 BES</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 3.54-3.57 GeV</td>
    </tr>
    <tr>
      <td>1776.3±2.4±1.4</td>
      <td>11k</td>
      <td>6 ALBRECHT</td>
      <td>92M ARG</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 9.4-10.6 GeV</td>
    </tr>
    <tr>
      <td>1783<sup>+3</sup><sub>-4</sub></td>
      <td>692</td>
      <td>7 BACINO</td>
      <td>78B DLCO</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 3.1-7.4 GeV</td>
    </tr>
    <tr>
      <td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td>
    </tr>
    <tr>
      <td>1776.81<sup>+0.25</sup><sub>-0.23</sub>±0.15</td>
      <td>81</td>
      <td>ANASHIN</td>
      <td>07 KEDR</td>
      <td>6.7 pb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 3.54-3.78 GeV</td>
    </tr>
    <tr>
      <td>1777.8±0.7±1.7</td>
      <td>35k</td>
      <td>8 BALEST</td>
      <td>93 CLEO</td>
      <td>Repl. by ANASTASSOV 97</td>
    </tr>
    <tr>
      <td>1776.9<sup>+0.4</sup><sub>-0.5</sub>±0.2</td>
      <td>14</td>
      <td>9 BAI</td>
      <td>92 BES</td>
      <td>Repl. by BAI 96</td>
    </tr>
  </tbody>
</table>

1. ADACHI 23C, AUBERT 09AK and BELOUS 07 fit τ pseudomass spectrum in $τ → ππ^+π^−ν_τ$ decays. Result assumes $m_{τπ} = 0$.

2. Previously also reported LEVICHEV 14. Supersedees ANASHIN 07.

3. ABLIKIM 14D fit $\sigma(e^+e^- \to \tau^+\tau^-)$ at different energies near threshold.

4. ABBIENDI 00A fit τ pseudomass spectrum in $τ → π^+ ≤ 2π^0ν_τ$ and $τ → π^+π^+π^+ ≤ 1π^0ν_τ$ decays. Result assumes $m_{τπ} = 0$.

5. BAI 96 fit $\sigma(e^+e^- \to \tau^+\tau^-)$ at different energies near threshold.

6. ALBRECHT 92m fit τ pseudomass spectrum in $τ^- → 2π^-π^+ν_τ$ decays. Result assumes $m_{τπ} = 0$.

7. BACINO 78b value comes from $e^±X^∓$ threshold. Published mass 1782 MeV increased by 1 MeV using the high precision $\psi(2S)$ mass measurement of ZHOLENTZ 80 to eliminate the absolute SPEAR energy calibration uncertainty.

8. BALEST 93 fit spectra of minimum kinematically allowed $τ$ mass in events of the type $e^+e^- \to \tau^+\tau^- \to (π^+nπ^0ν_τ)(π^-mπ^0ν_τ)$ $n ≤ 2$, $m ≤ 2$, $1 ≤ n+m ≤ 3$. If $m_{τπ} ≠ 0$, result increases by $(m^2_{τπ}/1100 \text{ MeV})$.

9. BAI 92 fit $\sigma(e^+e^- \to \tau^+\tau^-)$ near threshold using $eμ$ events.

$$ (m_{\tau^+} - m_{\tau^-})/m_{\text{average}} $$

A test of CPT invariance.

<table>
  <thead>
    <tr>
      <th>VALUE</th>
      <th>CL%</th>
      <th>DOCUMENT ID</th>
      <th>TECN</th>
      <th>COMMENT</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>&lt;2.8 × 10<sup>-4</sup></td>
      <td>90</td>
      <td>BELOUS</td>
      <td>07 BELL</td>
      <td>414 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>• • •</td>
      <td></td>
      <td></td>
      <td></td>
      <td>We do not use the following data for averages, fits, limits, etc. • • •</td>
    </tr>
    <tr>
      <td>&lt;5.5 × 10<sup>-4</sup></td>
      <td>90</td>
      <td>1 AUBERT</td>
      <td>09AK BABR</td>
      <td>423 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>&lt;3.0 × 10<sup>-3</sup></td>
      <td>90</td>
      <td>ABBIENDI</td>
      <td>00A OPAL</td>
      <td>1990-1995 LEP runs</td>
    </tr>
  </tbody>
</table>

1. AUBERT 09AK quote both the listed upper limit and $(m_{τ^+} - m_{τ^-})/m_{\text{average}} = (-3.4 ± 1.3 ± 0.3) × 10^{-4}$.

τ MEAN LIFE

<table>
  <thead>
    <tr>
      <th>VALUE (10<sup>-15</sup> s)</th>
      <th>EVTS</th>
      <th>DOCUMENT ID</th>
      <th>TECN</th>
      <th>COMMENT</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td colspan="5"><strong>290.3 ± 0.5 OUR AVERAGE</strong></td>
    </tr>
    <tr>
      <td>290.17 ± 0.53 ± 0.33</td>
      <td>1.1M</td>
      <td>BELOUS</td>
      <td>14 BELL</td>
      <td>711 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>290.9 ± 1.4 ± 1.0</td>
      <td></td>
      <td>ABDALLAH</td>
      <td>04T DLPH</td>
      <td>1991-1995 LEP runs</td>
    </tr>
    <tr>
      <td>293.2 ± 2.0 ± 1.5</td>
      <td></td>
      <td>ACCIARRI</td>
      <td>00B L3</td>
      <td>1991-1995 LEP runs</td>
    </tr>
    <tr>
      <td>290.1 ± 1.5 ± 1.1</td>
      <td></td>
      <td>BARATE</td>
      <td>97R ALEP</td>
      <td>1989-1994 LEP runs</td>
    </tr>
    <tr>
      <td>289.2 ± 1.7 ± 1.2</td>
      <td></td>
      <td>ALEXANDER</td>
      <td>96 OPAL</td>
      <td>1990-1994 LEP runs</td>
    </tr>
    <tr>
      <td>289.0 ± 2.8 ± 4.0</td>
      <td>57.4k</td>
      <td>BALEST</td>
      <td>96 CLEO</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
  </tbody>
</table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table>
  <tbody>
    <tr>
      <td>291.2 ± 2.0 ± 1.2</td>
      <td></td>
      <td>BARATE</td>
      <td>971 ALEP</td>
      <td>Repl. by BARATE 97R</td>
    </tr>
    <tr>
      <td>291.4 ± 3.0</td>
      <td></td>
      <td>ABREU</td>
      <td>96B DLPH</td>
      <td>Repl. by ABDALLAH 04T</td>
    </tr>
    <tr>
      <td>290.1 ± 4.0</td>
      <td>34k</td>
      <td>ACCIARRI</td>
      <td>96k L3</td>
      <td>Repl. by ACCIARRI 00B</td>
    </tr>
    <tr>
      <td>297 ± 9 ± 5</td>
      <td>1671</td>
      <td>ABE</td>
      <td>95Y SLD</td>
      <td>1992-1993 SLC runs</td>
    </tr>
    <tr>
      <td>304 ± 14 ± 7</td>
      <td>4100</td>
      <td>BATTLE</td>
      <td>92 CLEO</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
    <tr>
      <td>301 ± 29</td>
      <td>3780</td>
      <td>KLEINWORT</td>
      <td>89 JADE</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 35-46 GeV</td>
    </tr>
    <tr>
      <td>288 ± 16 ± 17</td>
      <td>807</td>
      <td>AMIDEI</td>
      <td>MRK2</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 29 GeV</td>
    </tr>
    <tr>
      <td>306 ± 20 ± 14</td>
      <td>695</td>
      <td>BRAUNSCH...</td>
      <td>88C TASS</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 36 GeV</td>
    </tr>
    <tr>
      <td>299 ± 15 ± 10</td>
      <td>1311</td>
      <td>ABACHI</td>
      <td>87C HRS</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 29 GeV</td>
    </tr>
    <tr>
      <td>295 ± 14 ± 11</td>
      <td>5696</td>
      <td>ALBRECHT</td>
      <td>87P ARG</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 9.3-10.6 GeV</td>
    </tr>
    <tr>
      <td>309 ± 17 ± 7</td>
      <td>3788</td>
      <td>BAND</td>
      <td>87B MAC</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 29 GeV</td>
    </tr>
    <tr>
      <td>325 ± 14 ± 18</td>
      <td>8470</td>
      <td>BEBEK</td>
      <td>87C CLEO</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 10.5 GeV</td>
    </tr>
    <tr>
      <td>460 ± 190</td>
      <td>102</td>
      <td>FELDMAN</td>
      <td>82 MRK2</td>
      <td>E<sup>ee</sup><sub>cm</sub> = 29 GeV</td>
    </tr>
  </tbody>
</table>

$$ (\tau_{\tau^+} - \tau_{\tau^-}) / \tau_{\text{average}} $$

Test of CPT invariance.

<table>
  <thead>
    <tr>
      <th>VALUE</th>
      <th>CL%</th>
      <th>DOCUMENT ID</th>
      <th>TECN</th>
      <th>COMMENT</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>&lt;7.0 × 10<sup>-3</sup></td>
      <td>90</td>
      <td>1 BELOUS</td>
      <td>14 BELL</td>
      <td>711 fb<sup>-1</sup>, E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td>
    </tr>
  </tbody>
</table>

1. BELOUS 14 quote limit on the absolute value of the relative lifetime difference.

τ MAGNETIC MOMENT ANOMALY

The $q^2$ dependence is expected to be small providing no thresholds are nearby.

$$ \tau_{\tau^+}(e\bar{\hbar}/2m_{\tau^+}) - 1 = (g_{\tau^-} - 2)/2 $$

For a theoretical calculation, for a $g_{\tau^-} = 2/2$ = 117 721(5) × $10^{-8}$, see EIDELMAN 07.

<table>
  <thead>
    <tr>
      <th>VALUE</th>
      <th>CL%</th>
      <th>DOCUMENT ID</th>
      <th>TECN</th>
      <th>COMMENT</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>-0.057 to 0.024</td>
      <td>95</td>
      <td>1 AAD</td>
      <td>23BMATLS</td>
      <td>γγ → τ<sup>+</sup>τ<sup>-</sup>, Pb-Pb</td>
    </tr>
    <tr>
      <td colspan="5">• • • We do not use the following data for averages, fits, limits, etc. • • •</td>
    </tr>
    <tr>
      <td>-0.041<sup>+0.012</sup><sub>-0.009</sub></td>
      <td>1.2 AAD</td>
      <td>23BMATLS</td>
      <td>γγ → τ<sup>+</sup>τ<sup>-</sup>, Pb-Pb</td>
      <td></td>
    </tr>
    <tr>
      <td>0.001<sup>+0.055</sup><sub>-0.089</sub></td>
      <td>2.3 TUMASYAN</td>
      <td>23AS CMS</td>
      <td>γγ → τ<sup>+</sup>τ<sup>-</sup>, Pb-Pb</td>
      <td></td>
    </tr>
    <tr>
      <td>-0.018<sup>+0.017</sup></td>
      <td>2.4 ABDALLAH</td>
      <td>04K DLPH</td>
      <td>e<sup>+</sup>e<sup>-</sup> → e<sup>+</sup>e<sup>-</sup>τ<sup>+</sup>τ<sup>-</sup></td>
      <td></td>
    </tr>
    <tr>
      <td>&lt; 0.107</td>
      <td>5 ACHARD</td>
      <td>04G L3</td>
      <td>e<sup>+</sup>e<sup>-</sup> → e<sup>+</sup>e<sup>-</sup>τ<sup>+</sup>τ<sup>-</sup></td>
      <td></td>
    </tr>
    <tr>
      <td>-0.007 to 0.005</td>
      <td>95</td>
      <td>6 GONZALEZ-S...00</td>
      <td>RVUE</td>
      <td>e<sup>+</sup>e<sup>-</sup> → τ<sup>+</sup>τ<sup>-</sup> and W → τν<sub>τ</sub></td>
    </tr>
    <tr>
      <td>-0.052 to 0.058</td>
      <td>95</td>
      <td>7 ACCIARRI</td>
      <td>98E L3</td>
      <td>1991-1995 LEP runs</td>
    </tr>
    <tr>
      <td>-0.068 to 0.065</td>
      <td>95</td>
      <td>8 ACKERSTAFF</td>
      <td>98N OPAL</td>
      <td>1990-1995 LEP runs</td>
    </tr>
    <tr>
      <td>-0.004 to 0.006</td>
      <td>95</td>
      <td>9 ESCRIBANO</td>
      <td>97 RVUE</td>
      <td>Z → τ<sup>+</sup>τ<sup>-</sup> at LEP</td>
    </tr>
    <tr>
      <td>&lt; 0.01</td>
      <td>95</td>
      <td>10 ESCRIBANO</td>
      <td>93 RVUE</td>
      <td>Z → τ<sup>+</sup>τ<sup>-</sup> at LEP</td>
    </tr>
    <tr>
      <td>&lt; 0.12</td>
      <td>90</td>
      <td>GRIFOLS</td>
      <td>91 RVUE</td>
      <td>Z → ττγ at LEP</td>
    </tr>
    <tr>
      <td>&lt; 0.023</td>
      <td>95</td>
      <td>11 SILVERMAN</td>
      <td>83 RVUE</td>
      <td>e<sup>+</sup>e<sup>-</sup> → τ<sup>+</sup>τ<sup>-</sup> at PETRA</td>
    </tr>
  </tbody>
</table>

1. AAD 23BM measurement is derived from $γγ → τ^+τ^-$ total cross-section from 1.44 $nb^{-1}$ LHC Pb-Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV. Authors report both the measured value and the corresponding 95% CL limit.
²Measurement ill-suited for a standard average because its likelihood appears to be remarkably non-Gaussian and asymmetric according to the model-dependent extraction procedure and the reported 95% CL limits.

³TUMASYAN 23aS measurement is derived from $γγ → τ^+τ^−$ total cross-section from 404 $μb^{-1}$ LHC Pb-Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV.

⁴ABDALLAH 04k measurement is derived from $e^+e^- → e^+e^-τ^+τ^−$ total cross-section measurements at $\sqrt{s}$ between 183 and 208 GeV. In addition to the measurement, the authors also quote 95% CL limits of > -0.052 and < 0.013.

⁵ACHARD 04g limit is derived from $e^+e^- → e^+e^-τ^+τ^−$ total cross-section measurements at $\sqrt{s}$ between 189 and 206 GeV, and is on the absolute value of the magnetic moment anomaly.

⁶GONZALEZ-SPRINBERG 00 use data on tau lepton production at LEP1, SLC, and LEP2, and data from colliders and LEP2 to determine limits. Assume imaginary component is zero.

⁷ACCIARRI 98e use $Z → τ^+τ^−γ$ events. In addition to the limits, the authors also quote a value of 0.004 ± 0.027 ± 0.023.

⁸ACKERSTAFF 98n use $Z → τ^+τ^−γ$ events. The limit applies to an average of the form factor for off-shell $τ$'s having $p^2$ ranging from $m_τ^2$ to $(M_Z-m_τ)^2$.

⁹ESCRIBANO 97 use preliminary experimental results.

¹⁰ESCRIBANO 93 limit derived from $Γ(Z → τ^+τ^-)$, and is on the absolute value of the magnetic moment anomaly.

¹¹SILVERMAN 83 limit is derived from $e^+e^- → τ^+τ^−$ total cross-section measurements for $q^2$ up to $(37 \text{ GeV})^2$.

## τ ELECTRIC DIPOLE MOMENT ($d_τ$)

A nonzero value is forbidden by both $T$ invariance and $P$ invariance.

The $q^2$ dependence is expected to be small providing no thresholds are nearby.

### Re($d_τ$)

<table><thead><tr><th>VALUE (10<sup>-16</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>-0.185 to 0.061</td><td>95</td><td>1 INAMI</td><td>22</td><td>E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>&lt; 2.3</td><td>90</td><td>2 GROZIN</td><td>09A</td><td>RVUE</td><td>From e EDM limit</td></tr><tr><td>&lt; 3.7</td><td>95</td><td>3 ABDALLAH</td><td>04K</td><td>DLPH</td><td>e<sup>+</sup>e<sup>-</sup> → e<sup>+</sup>e<sup>-</sup>τ<sup>+</sup>τ<sup>-</sup></td></tr><tr><td>&lt; 11.4</td><td>95</td><td>4 ACHARD</td><td>04G</td><td>L3</td><td>e<sup>+</sup>e<sup>-</sup> → e<sup>+</sup>e<sup>-</sup>τ<sup>+</sup>τ<sup>-</sup></td></tr><tr><td>- 0.22 to 0.45</td><td>95</td><td>5 INAMI</td><td>03</td><td>BELL</td><td>E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td></tr><tr><td>&lt; 4.6</td><td>95</td><td>6 ALBRECHT</td><td>00</td><td>ARG</td><td>E<sup>ee</sup><sub>cm</sub> = 10.4 GeV</td></tr><tr><td>&gt; -3.1 and &lt; 3.1</td><td>95</td><td>ACCIARRI</td><td>98E</td><td>L3</td><td>1991-1995 LEP runs</td></tr><tr><td>&gt; -3.8 and &lt; 3.6</td><td>95</td><td>7 ACKERSTAFF</td><td>98N</td><td>OPAL</td><td>1990-1995 LEP runs</td></tr><tr><td>&lt; 0.11</td><td>95</td><td>8,9 ESCRIBANO</td><td>97</td><td>RVUE</td><td>Z → τ<sup>+</sup>τ<sup>-</sup> at LEP</td></tr><tr><td>&lt; 0.5</td><td>95</td><td>10 ESCRIBANO</td><td>93</td><td>RVUE</td><td>Z → τ<sup>+</sup>τ<sup>-</sup> at LEP</td></tr><tr><td>&lt; 7</td><td>90</td><td>GRIFOLS</td><td>91</td><td>RVUE</td><td>Z → ττγ at LEP</td></tr><tr><td>&lt; 1.6</td><td>90</td><td>DELAGUILA</td><td>90</td><td>RVUE</td><td>e<sup>+</sup>e<sup>-</sup> → τ<sup>+</sup>τ<sup>-</sup></td></tr><tr><td></td><td></td><td></td><td></td><td></td><td>E<sup>ee</sup><sub>cm</sub> = 35 GeV</td></tr></tbody></table>

¹INAMI 22 use $e^+e^- → τ^+τ^-$ events from 833 fb$^{-1}$ of data. Also report a measurement of Re($d_τ$) = (-0.62 ± 0.63) × 10$^{-17}$ ecm.

²GROZIN 09a calculate the contribution to the electron electric dipole moment from the $τ$ electric dipole moment appearing in loops, which is $Δd_e = 6.9 \times 10^{-12}$ $d_τ$. Dividing the REGAN 02 upper limit $|d_e| \le 1.6 \times 10^{-27}$ e cm at CL=90% by 6.9 × 10$^{-12}$ gives this limit.

³ABDALLAH 04k limit is derived from $e^+e^- → e^+e^-τ^+τ^-$ total cross-section measurements at $\sqrt{s}$ between 183 and 208 GeV and is on the absolute value of $d_τ$.

⁴ACHARD 04g limit is derived from $e^+e^- → e^+e^-τ^+τ^-$ total cross-section measurements at $\sqrt{s}$ between 189 and 206 GeV, and is on the absolute value of $d_τ$.

⁵INAMI 03 use $e^+e^- → τ^+τ^-$ events.

⁶ALBRECHT 00 use $e^+e^- → τ^+τ^-$ events. Limit is on the absolute value of Re($d_τ$).

⁷ACKERSTAFF 98n use $Z → τ^+τ^−γ$ events. The limit applies to an average of the form factor for off-shell $τ$'s having $p^2$ ranging from $m_τ^2$ to $(M_Z-m_τ)^2$.

⁸ESCRIBANO 97 derive the relationship $|d_τ| = \cot \theta_W |d_W^τ|$ using effective Lagrangian methods, and use a conference result $|d_W^τ| < 5.8 \times 10^{-18}$ e cm at 95% CL (L. Silvestris, ICHEP96) to obtain this result.

⁹ESCRIBANO 97 use preliminary experimental results.

¹⁰ESCRIBANO 93 limit derived from $Γ(Z → τ^+τ^-)$, and is on the absolute value of the electric dipole moment.

### Im($d_τ$)

<table><thead><tr><th>VALUE (10<sup>-16</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>-0.103 to 0.023</td><td>95</td><td>1 INAMI</td><td>22</td><td>BELL E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>-0.25 to 0.008</td><td>95</td><td>2 INAMI</td><td>03</td><td>BELL E<sup>ee</sup><sub>cm</sub> = 10.6 GeV</td></tr><tr><td>&lt; 1.8</td><td>95</td><td>3 ALBRECHT</td><td>00</td><td>ARG E<sup>ee</sup><sub>cm</sub> = 10.4 GeV</td></tr></tbody></table>

¹INAMI 22 use $e^+e^- → τ^+τ^-$ events from 833 fb$^{-1}$ of data. Also report a measurement of Im($d_τ$) = (-0.40 ± 0.32) × 10$^{-17}$ ecm.

²INAMI 03 use $e^+e^- → τ^+τ^-$ events.

³ALBRECHT 00 use $e^+e^- → τ^+τ^-$ events. Limit is on the absolute value of Im($d_τ$).

## τ WEAK DIPOLE MOMENT ($d_W^τ$)

A nonzero value is forbidden by CP invariance.

The $q^2$ dependence is expected to be small providing no thresholds are nearby.

### Re($d_W^τ$)

<table><thead><tr><th>VALUE (10<sup>-17</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;0.50</td><td>95</td><td>1 HEISTER</td><td>03F</td><td>ALEP 1990-1995 LEP runs</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>&lt;3.0</td><td>90</td><td>1 ACCIARRI</td><td>98C</td><td>L3</td><td>1991-1995 LEP runs</td></tr><tr><td>&lt;0.56</td><td>95</td><td>ACKERSTAFF</td><td>97L</td><td>OPAL</td><td>1991-1995 LEP runs</td></tr><tr><td>&lt;0.78</td><td>95</td><td>2 AKERS</td><td>95F</td><td>OPAL</td><td>Repl. by ACKERSTAFF 97L</td></tr><tr><td>&lt;1.5</td><td>95</td><td>2 BUSKULIC</td><td>95C</td><td>ALEP</td><td>Repl. by HEISTER 03F</td></tr><tr><td>&lt;7.0</td><td>95</td><td>2 ACTON</td><td>92F</td><td>OPAL</td><td>Z → τ<sup>+</sup>τ<sup>-</sup> at LEP</td></tr><tr><td>&lt;3.7</td><td>95</td><td>2 BUSKULIC</td><td>92J</td><td>ALEP</td><td>Repl. by BUSKULIC 95C</td></tr></tbody></table>

¹Limit is on the absolute value of the real part of the weak dipole moment.

²Limit is on the absolute value of the real part of the weak dipole moment, and applies for $q^2 = m_τ^2$.

### Im($d_W^τ$)

<table><thead><tr><th>VALUE (10<sup>-17</sup> ecm)</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;1.1</td><td>95</td><td>1 HEISTER</td><td>03F</td><td>ALEP 1990-1995 LEP runs</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>&lt;1.5</td><td>95</td><td>ACKERSTAFF</td><td>97L</td><td>OPAL</td><td>1991-1995 LEP runs</td></tr><tr><td>&lt;4.5</td><td>95</td><td>2 AKERS</td><td>95F</td><td>OPAL</td><td>Repl. by ACKERSTAFF 97L</td></tr></tbody></table>

¹HEISTER 03F limit is on the absolute value of the imaginary part of the weak dipole moment.

²Limit is on the absolute value of the imaginary part of the weak dipole moment, and applies for $q^2 = m_τ^2$.

## τ WEAK ANOMALOUS MAGNETIC DIPOLE MOMENT ($α_W^τ$)

Electroweak radiative corrections are expected to contribute at the $10^{-6}$ level. See BERNABEU 95.

The $q^2$ dependence is expected to be small providing no thresholds are nearby.

### Re($α_W^τ$)

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;1.1 × 10<sup>-3</sup></td><td>95</td><td>1 HEISTER</td><td>03F</td><td>ALEP 1990-1995 LEP runs</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>&gt; -0.0024 and &lt; 0.0025</td><td>95</td><td>2 GONZALEZ-S..00</td><td>RVUE</td><td>e<sup>+</sup>e<sup>-</sup> → τ<sup>+</sup>τ<sup>-</sup> and W → τν<sub>τ</sub></td></tr><tr><td>&lt;4.5 × 10<sup>-3</sup></td><td>90</td><td>1 ACCIARRI</td><td>98C</td><td>L3</td><td>1991-1995 LEP runs</td></tr></tbody></table>

¹Limit is on the absolute value of the real part of the weak anomalous magnetic dipole moment.

²GONZALEZ-SPRINBERG 00 use data on tau lepton production at LEP1, SLC, and LEP2, and data from colliders and LEP2 to determine limits. Assume imaginary component is zero.

### Im($α_W^τ$)

<table><thead><tr><th>VALUE</th><th>CL%</th><th>DOCUMENT ID</th><th>TECN</th><th>COMMENT</th></tr></thead><tbody><tr><td>&lt;2.7 × 10<sup>-3</sup></td><td>95</td><td>1 HEISTER</td><td>03F</td><td>ALEP 1990-1995 LEP runs</td></tr></tbody></table>

• • • We do not use the following data for averages, fits, limits, etc. • • •

<table><tbody><tr><td>&lt;9.9 × 10<sup>-3</sup></td><td>90</td><td>1 ACCIARRI</td><td>98C</td><td>L3</td><td>1991-1995 LEP runs</td></tr></tbody></table>

¹Limit is on the absolute value of the imaginary part of the weak anomalous magnetic dipole moment.

## τ⁻ DECAY MODES

$τ^+$ modes are charge conjugates of the modes below. “$h^±$” stands for $π^±$ or $K^±$. “$μ^±$” stands for $e$ or $μ$. “Neutrals” stands for $γ$'s and/or $π^0$'s.

<table><thead><tr><th>Mode</th><th>Fraction (Γ<sub>f</sub>/Γ)</th><th>Scale factor/<br>Confidence level</th></tr></thead></table>

### Modes with one charged particle

Γ₁ particle⁻ ≥ 0 neutrals ≥ $0K^0ν_τ$ (85.24 ± 0.06) % ("1-prong")

Γ₂ particle⁻ ≥ 0 neutrals ≥ $0K^0Lν_τ$ (84.58 ± 0.06) %

Γ₃ $μ^-ν_μν_τ$ [a] (17.39 ± 0.04) %

Γ₄ $μ^-ν_μν_τγ$ [b] (3.67 ± 0.08) × 10⁻³

Γ₅ $e^-ν_eν_τ$ [a] (17.82 ± 0.04) %

Γ₆ $e^-ν_eν_τγ$ [b] (1.83 ± 0.05) %

Γ₇ $h^- ≥ 0K^0Lν_τ$ (12.03 ± 0.05) %

Γ₈ $h^-ν_τ$ (11.51 ± 0.05) %
<table><tbody><tr><td>Γ9</td><td>π<sup>-</sup>ν<sub>τ</sub></td><td>[a] (10.82 ± 0.05) %</td></tr><tr><td>Γ10</td><td>K<sup>-</sup>ν<sub>τ</sub></td><td>[a] (6.96 ± 0.10) × 10<sup>-3</sup></td></tr><tr><td>Γ11</td><td>h<sup>-</sup> ≥ 1 neutrals ν<sub>τ</sub></td><td>(37.00 ± 0.09) %</td></tr><tr><td>Γ12</td><td>h<sup>-</sup> ≥ 1π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(36.50 ± 0.09) %</td></tr><tr><td>Γ13</td><td>h<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(25.93 ± 0.09) %</td></tr><tr><td>Γ14</td><td>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (25.49 ± 0.09) %</td></tr><tr><td>Γ15</td><td>π<sup>-</sup>π<sup>0</sup>non-ρ(770)ν<sub>τ</sub></td><td>(3.0 ± 3.2) × 10<sup>-3</sup></td></tr><tr><td>Γ16</td><td>K<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (4.33 ± 0.15) × 10<sup>-3</sup></td></tr><tr><td>Γ17</td><td>h<sup>-</sup> ≥ 2π<sup>0</sup>ν<sub>τ</sub></td><td>(10.81 ± 0.09) %</td></tr><tr><td>Γ18</td><td>h<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub></td><td>(9.48 ± 0.10) %</td></tr><tr><td>Γ19</td><td>h<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(9.32 ± 0.10) %</td></tr><tr><td>Γ20</td><td>π<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (9.26 ± 0.10) %</td></tr><tr><td>Γ21</td><td>π<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>), scalar</td><td>&lt; 9 × 10<sup>-3</sup></td></tr><tr><td>Γ22</td><td>π<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>), vector</td><td>&lt; 7 × 10<sup>-3</sup></td></tr><tr><td>Γ23</td><td>K<sup>-</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (6.5 ± 2.2) × 10<sup>-4</sup></td></tr><tr><td>Γ24</td><td>h<sup>-</sup> ≥ 3π<sup>0</sup>ν<sub>τ</sub></td><td>(1.34 ± 0.07) %</td></tr><tr><td>Γ25</td><td>h<sup>-</sup> ≥ 3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.25 ± 0.07) %</td></tr><tr><td>Γ26</td><td>h<sup>-</sup>3π<sup>0</sup>ν<sub>τ</sub></td><td>(1.18 ± 0.07) %</td></tr><tr><td>Γ27</td><td>π<sup>-</sup>3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (1.04 ± 0.07) %</td></tr><tr><td>Γ28</td><td>K<sup>-</sup>3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η)</td><td>[a] (4.8 ± 2.1) × 10<sup>-4</sup></td></tr><tr><td>Γ29</td><td>h<sup>-</sup>4π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.6 ± 0.4) × 10<sup>-3</sup></td></tr><tr><td>Γ30</td><td>h<sup>-</sup>4π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η)</td><td>(1.1 ± 0.4) × 10<sup>-3</sup></td></tr><tr><td>Γ31</td><td>a<sub>1</sub>(1260)ν<sub>τ</sub> → π<sup>-</sup>γν<sub>τ</sub></td><td>(4.0 ± 1.5) × 10<sup>-4</sup></td></tr><tr><td>Γ32</td><td>K<sup>-</sup> ≥ 0π<sup>0</sup> ≥ 0K<sup>0</sup> ≥ 0γν<sub>τ</sub></td><td>(1.552 ± 0.029) %</td></tr><tr><td>Γ33</td><td>K<sup>-</sup> ≥ 1 (π<sup>0</sup> or K<sup>0</sup> or γ)ν<sub>τ</sub></td><td>(8.59 ± 0.28) × 10<sup>-3</sup></td></tr></tbody></table>

Modes with K⁰'s

<table><tbody><tr><td>Γ34</td><td>K<sup>0</sup><sub>S</sub> (particles)<sup>-</sup>ν<sub>τ</sub></td><td>(9.43 ± 0.28) × 10<sup>-3</sup></td></tr><tr><td>Γ35</td><td>h<sup>-</sup>K<sup>0</sup>ν<sub>τ</sub></td><td>(9.87 ± 0.14) × 10<sup>-3</sup></td></tr><tr><td>Γ36</td><td>π<sup>-</sup>K<sup>0</sup>ν<sub>τ</sub></td><td>[a] (8.38 ± 0.14) × 10<sup>-3</sup></td></tr><tr><td>Γ37</td><td>π<sup>-</sup>K<sup>0</sup>(non-K<sup>*</sup>(892)<sup>-</sup>)ν<sub>τ</sub></td><td>(5.4 ± 2.1) × 10<sup>-4</sup></td></tr><tr><td>Γ38</td><td>K<sup>-</sup>K<sup>0</sup>ν<sub>τ</sub></td><td>[a] (1.486 ± 0.034) × 10<sup>-3</sup></td></tr><tr><td>Γ39</td><td>K<sup>-</sup>K<sup>0</sup> ≥ 0π<sup>0</sup>ν<sub>τ</sub></td><td>(2.99 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ40</td><td>h<sup>-</sup>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(5.32 ± 0.13) × 10<sup>-3</sup></td></tr><tr><td>Γ41</td><td>π<sup>-</sup>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (3.82 ± 0.13) × 10<sup>-3</sup></td></tr><tr><td>Γ42</td><td>K<sup>-</sup>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(2.2 ± 0.5) × 10<sup>-3</sup></td></tr><tr><td>Γ43</td><td>K<sup>-</sup>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (1.50 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ44</td><td>π<sup>-</sup>K<sup>0</sup> ≥ 1π<sup>0</sup>ν<sub>τ</sub></td><td>(4.08 ± 0.25) × 10<sup>-3</sup></td></tr><tr><td>Γ45</td><td>π<sup>-</sup>K<sup>0</sup>π<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (2.6 ± 2.3) × 10<sup>-4</sup></td></tr><tr><td>Γ46</td><td>K<sup>-</sup>K<sup>0</sup>π<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 1.6 × 10<sup>-4</sup></td></tr><tr><td>Γ47</td><td>π<sup>-</sup>K<sup>0</sup>K<sup>0</sup>ν<sub>τ</sub></td><td>(1.55 ± 0.24) × 10<sup>-3</sup></td></tr><tr><td>Γ48</td><td>π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>ν<sub>τ</sub></td><td>[a] (2.35 ± 0.06) × 10<sup>-4</sup></td></tr><tr><td>Γ49</td><td>π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (1.08 ± 0.24) × 10<sup>-3</sup></td></tr><tr><td>Γ50</td><td>π<sup>-</sup>K<sup>0</sup><sub>L</sub>K<sup>0</sup>ν<sub>τ</sub></td><td>(2.35 ± 0.06) × 10<sup>-4</sup></td></tr><tr><td>Γ51</td><td>π<sup>-</sup>K<sup>0</sup><sub>L</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(3.6 ± 1.2) × 10<sup>-4</sup></td></tr><tr><td>Γ52</td><td>π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (1.82 ± 0.21) × 10<sup>-5</sup></td></tr><tr><td>Γ53</td><td>K<sup>*</sup>-K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub> → π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(1.08 ± 0.21) × 10<sup>-5</sup></td></tr><tr><td>Γ54</td><td>f<sub>1</sub>(1285)π<sup>-</sup>ν<sub>τ</sub> → π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(6.8 ± 1.5) × 10<sup>-6</sup></td></tr><tr><td>Γ55</td><td>f<sub>1</sub>(1420)π<sup>-</sup>ν<sub>τ</sub> → π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(2.4 ± 0.8) × 10<sup>-6</sup></td></tr><tr><td>Γ56</td><td>π<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (3.2 ± 1.2) × 10<sup>-4</sup></td></tr><tr><td>Γ57</td><td>π<sup>-</sup>K<sup>0</sup><sub>L</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(1.82 ± 0.21) × 10<sup>-5</sup></td></tr><tr><td>Γ58</td><td>K<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 6.3 × 10<sup>-7</sup></td></tr><tr><td>Γ59</td><td>K<sup>-</sup>K<sup>0</sup><sub>S</sub>K<sup>0</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 4.0 × 10<sup>-7</sup></td></tr><tr><td>Γ60</td><td>K<sup>0</sup>h<sup>+</sup>h<sup>-</sup> ≥ 0 neutrals ν<sub>τ</sub></td><td>&lt; 1.7 × 10<sup>-3</sup></td></tr><tr><td>Γ61</td><td>K<sup>0</sup>h<sup>+</sup>h<sup>-</sup>ν<sub>τ</sub></td><td>[a] (2.5 ± 2.0) × 10<sup>-4</sup></td></tr></tbody></table>

Modes with three charged particles

<table><tbody><tr><td>Γ62</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup> ≥ 0 neutrals ≥ 0K<sup>0</sup>ν<sub>τ</sub></td><td>(15.20 ± 0.06) %</td></tr><tr><td>Γ63</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup> ≥ 0 neutrals ν<sub>τ</sub> (ex. K<sup>0</sup> → π<sup>+</sup>π<sup>-</sup>)<br/>("3-prong")</td><td>(14.55 ± 0.06) %</td></tr><tr><td>Γ64</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>ν<sub>τ</sub></td><td>(9.80 ± 0.05) %</td></tr><tr><td>Γ65</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(9.46 ± 0.05) %</td></tr><tr><td>Γ66</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>(9.43 ± 0.05) %</td></tr><tr><td>Γ67</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>(9.31 ± 0.05) %</td></tr><tr><td>Γ68</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(9.02 ± 0.05) %</td></tr><tr><td>Γ69</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>), non-axial vector</td><td>&lt; 2.4 %</td></tr><tr><td>Γ70</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>[a] (8.99 ± 0.05) %</td></tr><tr><td>Γ71</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup> ≥ 1 neutrals ν<sub>τ</sub></td><td>(5.29 ± 0.05) %</td></tr></tbody></table>

<table><tbody><tr><td>Γ72</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup> ≥ 1π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(5.09 ± 0.05) %</td></tr><tr><td>Γ73</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(4.76 ± 0.05) %</td></tr><tr><td>Γ74</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(4.57 ± 0.05) %</td></tr><tr><td>Γ75</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>(2.79 ± 0.07) %</td></tr><tr><td>Γ76</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>(4.62 ± 0.05) %</td></tr><tr><td>Γ77</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(4.49 ± 0.05) %</td></tr><tr><td>Γ78</td><td>π<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>[a] (2.74 ± 0.07) %</td></tr><tr><td>Γ79</td><td>h<sup>-</sup>ρπ<sup>0</sup>ν<sub>τ</sub></td><td></td></tr><tr><td>Γ80</td><td>h<sup>-</sup>ρ<sup>+</sup>h<sup>-</sup>ν<sub>τ</sub></td><td></td></tr><tr><td>Γ81</td><td>h<sup>-</sup>ρ<sup>+</sup>h<sup>+</sup>ν<sub>τ</sub></td><td></td></tr><tr><td>Γ82</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup> ≥ 2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(5.17 ± 0.31) × 10<sup>-3</sup></td></tr><tr><td>Γ83</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>2π<sup>0</sup>ν<sub>τ</sub></td><td>(5.05 ± 0.31) × 10<sup>-3</sup></td></tr><tr><td>Γ84</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(4.95 ± 0.31) × 10<sup>-3</sup></td></tr><tr><td>Γ85</td><td>h<sup>-</sup>h<sup>-</sup>h<sup>+</sup>2π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω, η)</td><td>[a] (10 ± 4) × 10<sup>-4</sup></td></tr><tr><td>Γ86</td><td>h<sup>-</sup>h<sup>+</sup>3π<sup>0</sup>ν<sub>τ</sub></td><td>(2.13 ± 0.30) × 10<sup>-4</sup></td></tr><tr><td>Γ87</td><td>2π<sup>-</sup>π<sup>+</sup>3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.94 ± 0.30) × 10<sup>-4</sup></td></tr><tr><td>Γ88</td><td>2π<sup>-</sup>π<sup>+</sup>3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η, f<sub>1</sub>(1285))</td><td>(1.7 ± 0.4) × 10<sup>-4</sup></td></tr><tr><td>Γ89</td><td>2π<sup>-</sup>π<sup>+</sup>3π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η, ω, f<sub>1</sub>(1285))</td><td>(1.4 ± 2.7) × 10<sup>-5</sup></td></tr><tr><td>Γ90</td><td>K<sup>-</sup>h<sup>+</sup>h<sup>-</sup> ≥ 0 neutrals ν<sub>τ</sub></td><td>(6.29 ± 0.14) × 10<sup>-3</sup></td></tr><tr><td>Γ91</td><td>K<sup>-</sup>h<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(4.37 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ92</td><td>K<sup>-</sup>h<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(8.6 ± 1.2) × 10<sup>-4</sup></td></tr><tr><td>Γ93</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup> ≥ 0 neutrals ν<sub>τ</sub></td><td>(4.77 ± 0.14) × 10<sup>-3</sup></td></tr><tr><td>Γ94</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup> ≥ 0π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(3.73 ± 0.13) × 10<sup>-3</sup></td></tr><tr><td>Γ95</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>(3.45 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ96</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(2.93 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ97</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>[a] (2.93 ± 0.07) × 10<sup>-3</sup></td></tr><tr><td>Γ98</td><td>K<sup>-</sup>ρ<sup>0</sup>ν<sub>τ</sub> → K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>(1.4 ± 0.5) × 10<sup>-3</sup></td></tr><tr><td>Γ99</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.31 ± 0.12) × 10<sup>-3</sup></td></tr><tr><td>Γ100</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(7.9 ± 1.2) × 10<sup>-4</sup></td></tr><tr><td>Γ101</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η)</td><td>(7.6 ± 1.2) × 10<sup>-4</sup></td></tr><tr><td>Γ102</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>(3.7 ± 0.9) × 10<sup>-4</sup></td></tr><tr><td>Γ103</td><td>K<sup>-</sup>π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω, η)</td><td>(3.9 ± 1.4) × 10<sup>-4</sup></td></tr><tr><td>Γ104</td><td>K<sup>-</sup>π<sup>+</sup>K<sup>-</sup> ≥ 0 neut. ν<sub>τ</sub></td><td>&lt; 9 × 10<sup>-4</sup></td></tr><tr><td>Γ105</td><td>K<sup>-</sup>K<sup>+</sup>π<sup>-</sup> ≥ 0 neut. ν<sub>τ</sub></td><td>(1.496 ± 0.033) × 10<sup>-3</sup></td></tr><tr><td>Γ106</td><td>K<sup>-</sup>K<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>[a] (1.435 ± 0.027) × 10<sup>-3</sup></td></tr><tr><td>Γ107</td><td>K<sup>-</sup>K<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>[a] (6.1 ± 1.8) × 10<sup>-5</sup></td></tr><tr><td>Γ108</td><td>K<sup>-</sup>K<sup>+</sup>K<sup>-</sup>ν<sub>τ</sub></td><td>(2.2 ± 0.8) × 10<sup>-5</sup></td></tr><tr><td>Γ109</td><td>K<sup>-</sup>K<sup>+</sup>K<sup>-</sup>ν<sub>τ</sub> (ex. φ)</td><td>&lt; 2.5 × 10<sup>-6</sup></td></tr><tr><td>Γ110</td><td>K<sup>-</sup>K<sup>+</sup>K<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 4.8 × 10<sup>-6</sup></td></tr><tr><td>Γ111</td><td>π<sup>-</sup>K<sup>+</sup>π<sup>-</sup> ≥ 0 neut. ν<sub>τ</sub></td><td>&lt; 2.5 × 10<sup>-3</sup></td></tr><tr><td>Γ112</td><td>e<sup>-</sup>e<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>(2.8 ± 1.5) × 10<sup>-5</sup></td></tr><tr><td>Γ113</td><td>μ<sup>-</sup>e<sup>-</sup>e<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 3.2 × 10<sup>-5</sup></td></tr><tr><td>Γ114</td><td>π<sup>-</sup>e<sup>-</sup>e<sup>+</sup>ν<sub>τ</sub></td><td>seen</td></tr><tr><td>Γ115</td><td>π<sup>-</sup>μ<sup>-</sup>μ<sup>+</sup>ν<sub>τ</sub></td><td>&lt; 1.14 × 10<sup>-5</sup></td></tr></tbody></table>

Modes with five charged particles

<table><tbody><tr><td>Γ116</td><td>3h<sup>-</sup>2h<sup>+</sup> ≥ 0 neutrals ν<sub>τ</sub> (ex. K<sup>0</sup> → π<sup>+</sup>π<sup>-</sup>)<br/>("5-prong")</td><td>(9.9 ± 0.4) × 10<sup>-4</sup></td></tr><tr><td>Γ117</td><td>3h<sup>-</sup>2h<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(8.29 ± 0.31) × 10<sup>-4</sup></td></tr><tr><td>Γ118</td><td>3π<sup>-</sup>2π<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω)</td><td>(8.27 ± 0.31) × 10<sup>-4</sup></td></tr><tr><td>Γ119</td><td>3π<sup>-</sup>2π<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, ω, f<sub>1</sub>(1285))</td><td>[a] (7.75 ± 0.30) × 10<sup>-4</sup></td></tr><tr><td>Γ120</td><td>K<sup>-</sup>2π<sup>-</sup>2π<sup>+</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (6 ± 12) × 10<sup>-7</sup></td></tr><tr><td>Γ121</td><td>K<sup>+</sup>3π<sup>+</sup>π<sup>-</sup>ν<sub>τ</sub></td><td>&lt; 5.0 × 10<sup>-6</sup></td></tr><tr><td>Γ122</td><td>K<sup>+</sup>K<sup>-</sup>2π<sup>-</sup>π<sup>+</sup>ν<sub>τ</sub></td><td>&lt; 4.5 × 10<sup>-7</sup></td></tr><tr><td>Γ123</td><td>3h<sup>-</sup>2h<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.65 ± 0.11) × 10<sup>-4</sup></td></tr><tr><td>Γ124</td><td>3π<sup>-</sup>2π<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>(1.64 ± 0.11) × 10<sup>-4</sup></td></tr><tr><td>Γ125</td><td>3π<sup>-</sup>2π<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η, f<sub>1</sub>(1285))</td><td>(1.11 ± 0.10) × 10<sup>-4</sup></td></tr><tr><td>Γ126</td><td>3π<sup>-</sup>2π<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>, η, ω, f<sub>1</sub>(1285))</td><td>(3.8 ± 0.9) × 10<sup>-5</sup></td></tr><tr><td>Γ127</td><td>K<sup>-</sup>2π<sup>-</sup>2π<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub> (ex. K<sup>0</sup>)</td><td>[a] (1.1 ± 0.6) × 10<sup>-6</sup></td></tr><tr><td>Γ128</td><td>K<sup>+</sup>3π<sup>+</sup>π<sup>-</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 8 × 10<sup>-7</sup></td></tr><tr><td>Γ129</td><td>3h<sup>-</sup>2h<sup>+</sup>2π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 3.4 × 10<sup>-6</sup></td></tr></tbody></table>

Miscellaneous other allowed modes

<table><tbody><tr><td>Γ130</td><td>(5π)<sup>-</sup>ν<sub>τ</sub></td><td>(7.8 ± 0.5) × 10<sup>-3</sup></td></tr><tr><td>Γ131</td><td>4h<sup>-</sup>3h<sup>+</sup> ≥ 0 neutrals ν<sub>τ</sub> ("7-prong")</td><td>&lt; 3.0 × 10<sup>-7</sup></td></tr><tr><td>Γ132</td><td>4h<sup>-</sup>3h<sup>+</sup>ν<sub>τ</sub></td><td>&lt; 4.3 × 10<sup>-7</sup></td></tr><tr><td>Γ133</td><td>4h<sup>-</sup>3h<sup>+</sup>π<sup>0</sup>ν<sub>τ</sub></td><td>&lt; 2.5 × 10<sup>-7</sup></td></tr></tbody></table>
# Lepton Particle Listings

τ

Γ134 X⁻(S=-1)ντ ( 2.92 ± 0.04 ) %
Γ135 K⁺(892)⁻ ≥ 0 neutrals ≥ 0K⁰ντ ( 1.42 ± 0.18 ) % S=1.4

Γ136 K⁺(892)⁻ντ ( 1.20 ± 0.07 ) % S=1.8

Γ137 K⁺(892)⁻ντ → π⁻K⁰ντ ( 7.82 ± 0.26 ) × 10⁻³

Γ138 K⁺(892)⁰K⁻ ≥ 0 neutrals ντ ( 3.2 ± 1.4 ) × 10⁻³

Γ139 K⁺(892)⁰K⁻ντ ( 2.1 ± 0.4 ) × 10⁻³

Γ140 K⁺(892)⁰π⁻ ≥ 0 neutrals ντ ( 3.8 ± 1.7 ) × 10⁻³

Γ141 K⁺(892)⁰π⁻ντ ( 2.2 ± 0.5 ) × 10⁻³
Γ142 (K⁺(892)π⁻)ντ → π⁻K⁰π⁰ντ ( 1.0 ± 0.4 ) × 10⁻³

Γ143 K₁(1270)⁻ντ ( 4.7 ± 1.1 ) × 10⁻³

Γ144 K₁(1400)⁻ντ ( 1.7 ± 2.6 ) × 10⁻³ S=1.7

Γ145 K⁺(1410)⁻ντ ( 1.5 ± 1.4 ) × 10⁻³

Γ146 K⁰(1430)⁻ντ < 5 × 10⁻⁴ CL=95%

Γ147 K²(1430)⁻ντ < 3 × 10⁻³ CL=95%

Γ148 a₀(980)⁻ ≥ 0 neutrals ντ ( 9.9 ) × 10⁻⁵ CL=95%

Γ149 ηπ⁻ντ (a) ( 1.39 ± 0.07 ) × 10⁻³

Γ150 ηπ⁻π⁰ντ (a) ( 1.9 ± 0.4 ) × 10⁻⁴

Γ151 ηπ⁻π⁰π⁰ντ (a) ( 1.55 ± 0.08 ) × 10⁻⁴

Γ152 ηK⁻ντ (a) ( 1.38 ± 0.15 ) × 10⁻⁴

Γ153 ηK⁺(892)⁻ντ (a) ( 4.8 ± 1.2 ) × 10⁻⁵

Γ154 ηK⁻π⁰ντ (a) ( 9.4 ± 1.5 ) × 10⁻⁵ CL=90%

Γ155 ηK⁻π⁰(non-K⁺(892))ντ (a) ( 5.0 ) × 10⁻⁵ CL=90%

Γ156 ηK⁰π⁻ντ (a) ( 9.4 ± 1.5 ) × 10⁻⁵ CL=90%

Γ157 ηK⁰π⁻π⁰ντ (a) ( 5.0 ) × 10⁻⁵ CL=90%

Γ158 ηK⁻K⁰ντ (a) ( 9.0 ) × 10⁻⁶ CL=90%

Γ159 ηπ⁺π⁻π⁻ ≥ 0 neutrals ντ (a) ( 3.4 ± 0.6 ) × 10⁻⁵ CL=90%

Γ160 ηπ⁻π⁺π⁻ντ (ex.K⁰) (a) ( 2.20 ± 0.13 ) × 10⁻⁴

Γ161 ηπ⁻π⁺π⁻ντ (ex.K⁰,f₁(1285)) ( 9.9 ± 1.6 ) × 10⁻⁵ CL=90%

Γ162 ηa₁(1260)⁻ντ → ηπ⁻ρ⁰ντ (a) ( 3.9 ) × 10⁻⁴ CL=90%

Γ163 ηηπ⁻ντ (a) ( 7.4 ) × 10⁻⁶ CL=90%

Γ164 ηηπ⁻π⁰ντ (a) ( 2.0 ) × 10⁻⁴ CL=95%

Γ165 ηηK⁻ντ (a) ( 3.0 ) × 10⁻⁶ CL=90%

Γ166 η'(958)π⁻ντ (a) ( 4.0 ) × 10⁻⁶ CL=90%

Γ167 η'(958)π⁻π⁰ντ (a) ( 1.2 ) × 10⁻⁵ CL=90%

Γ168 η'(958)K⁻ντ (a) ( 2.4 ) × 10⁻⁶ CL=90%

Γ169 φπ⁻ντ (a) ( 3.4 ± 0.6 ) × 10⁻⁵ CL=90%

Γ170 φK⁻ντ (a) ( 4.4 ± 1.6 ) × 10⁻⁵ CL=90%

Γ171 f₁(1285)π⁻ντ (a) ( 5.2 ± 0.4 ) × 10⁻⁵ CL=90%

Γ172 f₁(1285)π⁻ντ → ηπ⁻π⁺π⁻ντ (a) ( 1.18 ± 0.07 ) × 10⁻⁴ S=1.3

Γ173 f₁(1285)π⁻ντ → 3π⁻2π⁺ντ (a) ( 5.2 ± 0.4 ) × 10⁻⁵ CL=90%

Γ174 π(1300)⁻ντ → (ρπ)⁻ντ → (3π)⁻ντ (a) ( 1.0 ) × 10⁻⁴ CL=90%

Γ175 π(1300)⁻ντ → ((ππ)S-wave π)⁻ντ → (3π)⁻ντ (a) ( 1.9 ) × 10⁻⁴ CL=90%

Γ176 h⁻ω ≥ 0 neutrals ντ (a) ( 2.40 ± 0.08 ) % CL=90%

Γ177 h⁻ωντ (a) ( 1.99 ± 0.06 ) % CL=90%

Γ178 π⁻ωντ (a) ( 1.95 ± 0.06 ) % CL=90%

Γ179 K⁻ωντ (a) ( 4.1 ± 0.9 ) × 10⁻⁴ CL=90%

Γ180 h⁻ωπ⁰ντ (a) ( 4.1 ± 0.4 ) × 10⁻³ CL=90%

Γ181 h⁻ω2π⁰ντ (a) ( 1.4 ± 0.5 ) × 10⁻⁴ CL=90%

Γ182 π⁻ω2π⁰ντ (a) ( 7.2 ± 1.6 ) × 10⁻⁵ CL=90%

Γ183 h⁻2ωντ (a) ( 5.4 ) × 10⁻⁷ CL=90%

Γ184 2h⁻h⁺ωντ (a) ( 1.20 ± 0.22 ) × 10⁻⁴ CL=90%

Γ185 2π⁻π⁺ωντ (ex.K⁰) (a) ( 8.4 ± 0.6 ) × 10⁻⁵ CL=90%

Γ186 e⁻γ (a) ( 3.3 ) × 10⁻⁸ CL=90%

Γ187 e⁻γγ (a) ( 2.5 ) × 10⁻⁴ CL=90%

Γ188 μ⁻γ (a) ( 4.2 ) × 10⁻⁸ CL=90%

Γ189 μ⁻γγ (a) ( 5.8 ) × 10⁻⁴ CL=90%

Γ190 e⁻π⁰ (a) ( 8.0 ) × 10⁻⁸ CL=90%

Γ191 μ⁻π⁰ (a) ( 1.1 ) × 10⁻⁷ CL=90%

Γ192 e⁻K⁰S (a) ( 2.6 ) × 10⁻⁸ CL=90%

Γ193 μ⁻K⁰S (a) ( 2.3 ) × 10⁻⁸ CL=90%

Γ194 e⁻η (a) ( 9.2 ) × 10⁻⁸ CL=90%

Γ195 μ⁻η (a) ( 6.5 ) × 10⁻⁸ CL=90%

Γ196 e⁻ρ⁰ (a) ( 2.2 ) × 10⁻⁸ CL=90%

Γ197 μ⁻ρ⁰ (a) ( 1.7 ) × 10⁻⁸ CL=90%

Γ198 e⁻ω (a) ( 2.4 ) × 10⁻⁸ CL=90%

Γ199 μ⁻ω (a) ( 3.9 ) × 10⁻⁸ CL=90%

Γ200 e⁻K⁺(892)⁰ (a) ( 1.9 ) × 10⁻⁸ CL=90%

Γ201 μ⁻K⁺(892)⁰ (a) ( 2.9 ) × 10⁻⁸ CL=90%

Γ202 e⁻K⁺(892)⁰ (a) ( 1.7 ) × 10⁻⁸ CL=90%

Γ203 μ⁻K⁺(892)⁰ (a) ( 4.3 ) × 10⁻⁸ CL=90%

Γ204 e⁻η'(958) (a) ( 1.6 ) × 10⁻⁷ CL=90%

Γ205 μ⁻η'(958) (a) ( 1.3 ) × 10⁻⁷ CL=90%

Γ206 e⁻f₀(980) → e⁻π⁺π⁻ (a) ( 3.2 ) × 10⁻⁸ CL=90%

Γ207 μ⁻f₀(980) → μ⁻π⁺π⁻ (a) ( 3.4 ) × 10⁻⁸ CL=90%

Γ208 e⁻φ (a) ( 2.0 ) × 10⁻⁸ CL=90%

Γ209 μ⁻φ (a) ( 2.3 ) × 10⁻⁸ CL=90%

Γ210 e⁻e⁺e⁻ (a) ( 2.7 ) × 10⁻⁸ CL=90%

Γ211 e⁻μ⁺μ⁻ (a) ( 2.7 ) × 10⁻⁸ CL=90%

Γ212 e⁺μ⁺μ⁻ (a) ( 1.7 ) × 10⁻⁸ CL=90%

Γ213 μ⁻e⁺e⁻ (a) ( 1.8 ) × 10⁻⁸ CL=90%

Γ214 μ⁺e⁺e⁻ (a) ( 1.5 ) × 10⁻⁸ CL=90%

Γ215 μ⁻μ⁺μ⁻ (a) ( 2.1 ) × 10⁻⁸ CL=90%

Γ216 e⁻π⁺π⁻ (a) ( 2.3 ) × 10⁻⁸ CL=90%

Γ217 e⁺π⁺π⁻ (a) ( L ) ( 2.0 ) × 10⁻⁸ CL=90%

Γ218 μ⁻π⁺π⁻ (a) ( L ) ( 2.1 ) × 10⁻⁸ CL=90%

Γ219 μ⁺π⁺π⁻ (a) ( L ) ( 3.9 ) × 10⁻⁸ CL=90%

Γ220 e⁻π⁺K⁻ (a) ( L ) ( 3.7 ) × 10⁻⁸ CL=90%

Γ221 e⁻π⁺K⁺ (a) ( L ) ( 3.1 ) × 10⁻⁸ CL=90%

Γ222 e⁺π⁺K⁻ (a) ( L ) ( 3.2 ) × 10⁻⁸ CL=90%

Γ223 e⁻K⁰K⁰S (a) ( L ) ( 7.1 ) × 10⁻⁸ CL=90%

Γ224 e⁻K⁺K⁻ (a) ( L ) ( 3.4 ) × 10⁻⁸ CL=90%

Γ225 e⁺K⁻K⁻ (a) ( L ) ( 3.3 ) × 10⁻⁸ CL=90%

Γ226 μ⁻π⁺K⁻ (a) ( L ) ( 8.6 ) × 10⁻⁸ CL=90%

Γ227 μ⁻π⁻K⁺ (a) ( L ) ( 4.5 ) × 10⁻⁸ CL=90%

Γ228 μ⁺π⁻K⁻ (a) ( L ) ( 4.8 ) × 10⁻⁸ CL=90%

Γ229 μ⁻K⁰K⁰S (a) ( L ) ( 8.0 ) × 10⁻⁸ CL=90%

Γ230 μ⁻K⁺K⁻ (a) ( L ) ( 4.4 ) × 10⁻⁸ CL=90%

Γ231 μ⁺K⁻K⁻ (a) ( L ) ( 4.7 ) × 10⁻⁸ CL=90%

Γ232 e⁻π⁰π⁰ (a) ( L ) ( 6.5 ) × 10⁻⁶ CL=90%

Γ233 μ⁻π⁰π⁰ (a) ( L ) ( 1.4 ) × 10⁻⁵ CL=90%

Γ234 e⁻ηη (a) ( L ) ( 3.5 ) × 10⁻⁵ CL=90%

Γ235 μ⁻ηη (a) ( L ) ( 6.0 ) × 10⁻⁵ CL=90%

Γ236 e⁻π⁰η (a) ( L ) ( 2.4 ) × 10⁻⁵ CL=90%

Γ237 μ⁻π⁰η (a) ( L ) ( 2.2 ) × 10⁻⁵ CL=90%

Γ238 ρe⁻e⁺ (a) ( L,B ) ( 3.0 ) × 10⁻⁸ CL=90%

Γ239 ρe⁺e⁻ (a) ( L,B ) ( 3.0 ) × 10⁻⁸ CL=90%

Γ240 ρe⁺μ⁻ (a) ( L,B ) ( 2.0 ) × 10⁻⁸ CL=90%

Γ241 ρe⁻μ⁺ (a) ( L,B ) ( 1.8 ) × 10⁻⁸ CL=90%

Γ242 ρμ⁻μ⁻ (a) ( L,B ) ( 4.0 ) × 10⁻⁸ CL=90%

Γ243 ρμ⁺μ⁺ (a) ( L,B ) ( 1.8 ) × 10⁻⁸ CL=90%

Γ244 ργ (a) ( L,B ) ( 3.5 ) × 10⁻⁶ CL=90%

Γ245 ρπ⁰ (a) ( L,B ) ( 1.5 ) × 10⁻⁵ CL=90%

Γ246 ρ2π⁰ (a) ( L,B ) ( 3.3 ) × 10⁻⁵ CL=90%

Γ247 ρη (a) ( L,B ) ( 8.9 ) × 10⁻⁶ CL=90%

Γ248 ρπ⁰η (a) ( L,B ) ( 2.7 ) × 10⁻⁵ CL=90%

Γ249 Λπ⁻ (a) ( L,B ) ( 7.2 ) × 10⁻⁸ CL=90%

Γ250 Λπ⁻ (a) ( L,B ) ( 1.4 ) × 10⁻⁷ CL=90%

Γ251 e⁻light boson (a) ( L,F ) ( 9 ) × 10⁻⁴ CL=95%

Γ252 μ⁻light boson (a) ( L,F ) ( 6 ) × 10⁻⁴ CL=95%

[a] Basis mode for the τ.

[b] See the Particle Listings below for the energy limits used in this measurement.

L means lepton number violation (e.g. τ⁻ → e⁺π⁻π⁻). Following common usage, LF means lepton family violation and not lepton number violation (e.g. τ⁻ → e⁺π⁺π⁻). B means baryon number violation.

Γ186 e⁻γ (a) ( 3.3 ) × 10⁻⁸ CL=90%

Γ187 e⁻γγ (a) ( 2.5 ) × 10⁻⁴ CL=90%

Γ188 μ⁻γ (a) ( 4.2 ) × 10⁻⁸ CL=90%

Γ189 μ⁻γγ (a) ( 5.8 ) × 10⁻⁴ CL=90%

Γ190 e⁻π⁰ (a) ( 8.0 ) × 10⁻⁸ CL=90%

Γ191 μ⁻π⁰ (a) ( 1.1 ) × 10⁻⁷ CL=90%

Γ192 e⁻K⁰S (a) ( 2.6 ) × 10⁻⁸ CL=90%

Γ193 μ⁻K⁰S (a) ( 2.3 ) × 10⁻⁸ CL=90%

Γ194 e⁻η (a) ( 9.2 ) × 10⁻⁸ CL=90%
CONSTRAINED FIT INFORMATION

An overall fit to 85 branching ratios uses 170 measurements and one constraint to determine 46 parameters. The overall fit has a $\chi^2 = 135.0$ for 125 degrees of freedom.

The following off-diagonal array elements are the correlation coefficients $\langle \delta x_i \delta x_j \rangle / (\delta x_i \delta x_j)$, in percent, from the fit to the branching fractions, $x_i \equiv \Gamma_i / \Gamma_{\text{total}}$. The fit constrains the $x_i$ whose labels appear in this array to sum to one.

<table><tbody><tr><td>x<sub>5</sub></td><td>18</td></tr><tr><td>x<sub>9</sub></td><td>2 -1</td></tr><tr><td>x<sub>10</sub></td><td>3 4 5</td></tr><tr><td>x<sub>14</sub></td><td>-18 -19 -17 -5</td></tr><tr><td>x<sub>16</sub></td><td>-1 -1 0 -2 -9</td></tr><tr><td>x<sub>20</sub></td><td>-11 -11 -14 -4 -46 -1</td></tr><tr><td>x<sub>23</sub></td><td>-1 0 -2 -3 -1 -14 -10</td></tr><tr><td>x<sub>27</sub></td><td>-6 -5 -10 -1 0 1 -39 1</td></tr><tr><td>x<sub>28</sub></td><td>0 -1 -1 -2 0 -13 -3 -23 -11</td></tr><tr><td>x<sub>30</sub></td><td>-4 -3 -11 -1 -9 0 7 -2 -44 2</td></tr><tr><td>x<sub>36</sub></td><td>-2 -2 -3 -1 -1 -1 -2 0 -1 0</td></tr><tr><td>x<sub>38</sub></td><td>-1 -1 1 0 0 0 0 -2 0 -2</td></tr><tr><td>x<sub>41</sub></td><td>-2 -2 -2 -1 -1 0 -2 0 -1 0</td></tr><tr><td>x<sub>43</sub></td><td>-1 -1 -1 -1 0 -3 0 -5 0 -5</td></tr><tr><td>x<sub>45</sub></td><td>-5 -5 -5 -2 -3 -1 -4 -2 -1 -2</td></tr><tr><td>x<sub>48</sub></td><td>-1 -1 2 0 -1 2 -1 -1 0 -1</td></tr><tr><td>x<sub>49</sub></td><td>-5 -5 -5 -2 -3 -1 -5 -2 -1 -2</td></tr><tr><td>x<sub>52</sub></td><td>0 0 0 0 0 0 0 -1 0 -1</td></tr><tr><td>x<sub>56</sub></td><td>-2 -2 -2 -1 -1 -2 -1 -1 -1</td></tr><tr><td>x<sub>61</sub></td><td>-5 -5 -5 -2 -3 -1 -4 -2 -1 -2</td></tr><tr><td>x<sub>70</sub></td><td>-7 -9 4 -2 -6 3 -12 -2 -7 -1</td></tr><tr><td>x<sub>78</sub></td><td>-4 -4 -5 0 -9 0 1 1 -1 1</td></tr><tr><td>x<sub>85</sub></td><td>0 0 -2 0 -2 0 0 0 2 0</td></tr><tr><td>x<sub>89</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>97</sub></td><td>-2 -2 -1 -1 -1 -1 -3 -1 -2 -1</td></tr><tr><td>x<sub>103</sub></td><td>1 1 0 -1 1 -1 -1 -1 0 -1</td></tr><tr><td>x<sub>106</sub></td><td>-1 -2 2 -1 -1 1 -2 -1 -1 -1</td></tr><tr><td>x<sub>107</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>119</sub></td><td>-1 -1 1 0 -1 1 -2 -1 -1 0</td></tr><tr><td>x<sub>120</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>126</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>127</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>150</sub></td><td>-1 -1 -1 0 -1 0 -2 -1 0 -1</td></tr><tr><td>x<sub>151</sub></td><td>-1 -1 0 0 -1 0 -1 0 0 0</td></tr><tr><td>x<sub>152</sub></td><td>0 0 0 0 0 0 0 -1 0 -1</td></tr><tr><td>x<sub>154</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>156</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>160</sub></td><td>-1 -1 1 0 -1 1 -1 0 -1 0</td></tr><tr><td>x<sub>170</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>173</sub></td><td>0 -1 1 0 0 1 -1 0 0 0</td></tr><tr><td>x<sub>178</sub></td><td>-3 -3 -3 -1 -4 0 -1 0 -1 0</td></tr><tr><td>x<sub>179</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>180</sub></td><td>-2 -2 -5 -1 -3 0 -2 -1 2 -1</td></tr><tr><td>x<sub>182</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>185</sub></td><td>-1 -1 0 0 -1 1 -1 0 0 0</td></tr><tr><td>x<sub>3</sub></td><td>x<sub>5</sub></td><td>x<sub>9</sub></td><td>x<sub>10</sub></td><td>x<sub>14</sub></td><td>x<sub>16</sub></td><td>x<sub>20</sub></td><td>x<sub>23</sub></td><td>x<sub>27</sub></td><td>x<sub>28</sub></td></tr></tbody></table>

<table><tbody><tr><td>x<sub>36</sub></td><td>0</td></tr><tr><td>x<sub>38</sub></td><td>0 -15</td></tr><tr><td>x<sub>41</sub></td><td>0 -13 2</td></tr><tr><td>x<sub>43</sub></td><td>0 -1 -14 -20</td></tr><tr><td>x<sub>45</sub></td><td>0 -3 0 -6 0</td></tr><tr><td>x<sub>48</sub></td><td>0 -2 3 -4 1 0</td></tr><tr><td>x<sub>49</sub></td><td>0 -5 0 -4 -1 -10 -1</td></tr><tr><td>x<sub>52</sub></td><td>0 1 5 -1 6 0 -7 0</td></tr><tr><td>x<sub>56</sub></td><td>0 -2 0 -2 -1 -4 0 -8 0</td></tr><tr><td>x<sub>61</sub></td><td>0 -2 0 -2 0 -4 0 -4 0 -2</td></tr><tr><td>x<sub>70</sub></td><td>-5 -2 3 -2 -1 -4 5 -4 0 -2</td></tr><tr><td>x<sub>78</sub></td><td>3 1 -1 1 0 2 -1 2 0 1</td></tr><tr><td>x<sub>85</sub></td><td>2 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>89</sub></td><td>0 0 0 0 0 0 0 -1 0</td></tr><tr><td>x<sub>97</sub></td><td>-1 -1 0 -1 0 -2 0 -2 0 -1</td></tr><tr><td>x<sub>103</sub></td><td>-1 -1 0 -1 0 -1 0 -1 0 -1</td></tr><tr><td>x<sub>106</sub></td><td>-1 -1 1 0 0 0 -1 2 -1 0</td></tr><tr><td>x<sub>107</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>119</sub></td><td>-1 -1 1 0 0 -1 2 -1 0 0</td></tr><tr><td>x<sub>120</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>126</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>127</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>150</sub></td><td>-2 -1 0 0 0 -1 0 -1 0 0</td></tr><tr><td>x<sub>151</sub></td><td>0 0 0 0 0 0 -1 0 -1 0</td></tr><tr><td>x<sub>152</sub></td><td>0 0 1 0 0 0 1 0 0 0</td></tr><tr><td>x<sub>154</sub></td><td>0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>156</sub></td><td>0 0 0 0 0 0 0 -1 0 0</td></tr><tr><td>x<sub>160</sub></td><td>-1 0 1 0 0 0 -1 1 -1 0 0</td></tr><tr><td>x<sub>170</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>173</sub></td><td>-1 0 1 0 0 0 1 0 0 0</td></tr><tr><td>x<sub>178</sub></td><td>1 0 0 0 0 -1 0 -1 0 0</td></tr><tr><td>x<sub>179</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>180</sub></td><td>2 -1 0 0 0 -1 0 -1 0 0</td></tr><tr><td>x<sub>182</sub></td><td>0 0 0 0 0 0 0 0 0 0</td></tr><tr><td>x<sub>185</sub></td><td>-1 0 1 0 0 0 1 -1 0 0</td></tr><tr><td>x<sub>30</sub></td><td>x<sub>36</sub></td><td>x<sub>38</sub></td><td>x<sub>41</sub></td><td>x<sub>43</sub></td><td>x<sub>45</sub></td><td>x<sub>48</sub></td><td>x<sub>49</sub></td><td>x<sub>52</sub></td><td>x<sub>56</sub></td></tr><tr><td>x<sub>70</sub></td><td>-4</td></tr><tr><td>x<sub>78</sub></td><td>2 -19</td></tr><tr><td>x<sub>85</sub></td><td>0 -1 -8</td></tr><tr><td>x<sub>89</sub></td><td>0 -1 -1 0</td></tr><tr><td>x<sub>97</sub></td><td>-2 19 -6 0 0</td></tr><tr><td>x<sub>103</sub></td><td>-1 -4 -14 -1 0 -1</td></tr><tr><td>x<sub>106</sub></td><td>-1 15 -4 0 0 0 -1</td></tr><tr><td>x<sub>107</sub></td><td>0 -1 -1 0 0 0 -3 0</td></tr><tr><td>x<sub>119</sub></td><td>-1 3 -1 0 -4 -1 0 1 0</td></tr><tr><td>x<sub>120</sub></td><td>0 0 0 0 0 0 0 0 0 -1</td></tr><tr><td>x<sub>126</sub></td><td>0 0 0 0 0 0 0 0 0 3</td></tr><tr><td>x<sub>127</sub></td><td>0 0 0 0 0 0 0 0 0 -1</td></tr><tr><td>x<sub>150</sub></td><td>-1 0 0 -5 0 0 0 0 0 0</td></tr><tr><td>x<sub>151</sub></td><td>-1 0 0 0 -11 0 0 0 0 0</td></tr><tr><td>x<sub>152</sub></td><td>0 2 0 0 0 0 -1 1 0 1</td></tr><tr><td>x<sub>154</sub></td><td>0 0 0 -1 0 0 0 0 0 0</td></tr><tr><td>x<sub>156</sub></td><td>0 0 0 0 -2 0 0 0 0 0</td></tr><tr><td>x<sub>160</sub></td><td>-1 1 -1 0 -8 -1 0 1 0 46</td></tr><tr><td>x<sub>170</sub></td><td>0 -1 0 0 0 1 0 1 0 0</td></tr><tr><td>x<sub>173</sub></td><td>0 1 0 0 -2 0 0 1 0 34</td></tr><tr><td>x<sub>178</sub></td><td>-1 -9 -67 -3 0 -2 10 -2 0 -1</td></tr><tr><td>x<sub>179</sub></td><td>0 0 12 0 0 -2 -58 0 0 0</td></tr><tr><td>x<sub>180</sub></td><td>-1 -2 -11 -64 -1 -1 -1 -1 0 0</td></tr><tr><td>x<sub>182</sub></td><td>0 0 0 0 -16 0 0 0 0 7</td></tr><tr><td>x<sub>185</sub></td><td>0 1 -1 0 -4 0 0 1 0 39</td></tr><tr><td>x<sub>61</sub></td><td>x<sub>70</sub></td><td>x<sub>78</sub></td><td>x<sub>85</sub></td><td>x<sub>89</sub></td><td>x<sub>97</sub></td><td>x<sub>103</sub></td><td>x<sub>106</sub></td><td>x<sub>107</sub></td><td>x<sub>119</sub></td></tr></tbody></table>