Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

I G (J P ) = 1− (0− )π±We have omitted some results that have been superseded by later
experiments. The omitted results may be found in our 1988 edition
Physics Letters B204 1 (1988).

π ± MASS
The most accurate charged pion mass measurements are based upon xray wavelength measurements for transitions in π − -mesonic atoms. The
observed line is the blend of three components, corresponding to different
K-shell occupancies. JECKELMANN 94 revisits the occupancy question,with the conclusion that two sets of occupancy ratios, resulting in two different pion masses (Solutions A and B), are equally probable. We choose
the higher Solution B since only this solution is consistent with a positive
mass-squared for the muon neutrino, given the precise muon momentum
measurements now available (DAUM 91, ASSAMAGAN 94, and ASSAMAGAN 96) for the decay of pions at rest. Earlier mass determinations with
pi-mesonic atoms may have used incorrect K-shell screening corrections.
Measurements with an error of > 0.005 MeV have been omitted from thisListing.
VALUE (MeV)

DOCUMENT ID

TECN

CHG

COMMENT

139.57039± 0.00018 OUR FIT Error includes scale factor of 1.8.
139.57039± 0.00017 OUR AVERAGE Error includes scale factor of 1.6. See the ideogram
below.
1 DAUM
139.57021± 0.00014
19 SPEC
π + → µ+ ν µ2139.57077± 0.00018
TRASSINELLI 16 CNTR
X-ray transitions in pionicN2
3 LENZ
139.57071± 0.00053
98 CNTR −pionic N2-atoms gas target
4 JECKELMANN 94 CNTR −139.56995± 0.00035
π − atom, Soln. B• • • We do not use the following data for averages, fits, limits, etc. • • •5 ASSAMAGAN 96 SPEC +139.57022± 0.00014
π + → µ+ ν µ
6 JECKELMANN 94 CNTR −139.56782± 0.00037
π − atom, Soln. A
7139.56996± 0.00067
DAUM
91 SPEC +π + → µ+ ν
8139.56752± 0.00037
JECKELMANN 86B CNTR −Mesonic atoms
7 ABELA
139.5704 ± 0.0011
84 SPEC +See DAUM 91
9 LU
139.5664 ± 0.0009
80 CNTR −Mesonic atoms
139.5686 ± 0.0020
CARTER
76 CNTR −Mesonic atoms
9,10 MARUSHEN... 76 CNTR −139.5660 ± 0.0024
Mesonic atoms
1 DAUM 19 value is based on their previous (1991+1996) measurements of the µ+momentum of 29.79200 ± 0.00011 MeV for π + decay at rest. It also uses m µ =105.6583745 ± 0.0000024 MeV, and assumes conservatively m ν = 2.0 ± 2.0 MeV. Itµ
is the most precise charged pion mass determination.
2 TRASSINELLI 16 use the muonic oxygen line for online energy calibration of the pionicline.
3 LENZ 98 result does not suffer K-electron configuration uncertainties as does JECKELMANN 94.

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

4 JECKELMANN 94 Solution B (dominant 2-electron K-shell occupancy), chosen for consistency with positive m 2 .
νµ5 ASSAMAGAN 96 measures the µ+ momentum p in π + → µ+ ν decay at rest toµµ
be 29.79200 ± 0.00011 MeV/c. Combined with the µ+ mass and the assumption m νµ= 0, this gives the π + mass above; if m ν> 0, m + given above is a lower limit.
πµand (assuming CPT) the π − mass of JECKELMANN 94,

Combined instead with m µpµ gives an upper limit on m ν(see the νµ ).
µ6 JECKELMANN 94 Solution A (small 2-electron K-shell occupancy) in combination witheither the DAUM 91 or ASSAMAGAN 94 pion decay muon momentum measurement
yields a significantly negative m 2 . It is accordingly not used in our fits.
νµ7 The DAUM 91 value includes the ABELA 84 result. The value is based on a measurementof the µ+ momentum for π + decay at rest, pµ = 29.79179 ± 0.00053 MeV, uses m µ =105.658389 ± 0.000034 MeV, and assumes that m ν = 0. The last assumption meansµthat in fact the value is a lower limit.
8 JECKELMANN 86B gives m /m = 273.12677(71). We use m = 0.51099906(15)πeeMeV from COHEN 87. The authors note that two solutions for the probability distributionof K-shell occupancy fit equally well, and use other data to choose the lower of the two
possible π ± masses.
9 These values are scaled with a new wavelength-energy conversion factor Vλ =1.23984244(37) × 10−6 eV m from COHEN 87. The LU 80 screening correction relies upon a theoretical calculation of inner-shell refilling rates.
10 This MARUSHENKO 76 value used at the authors’ request to use the accepted set ofcalibration γ energies. Error increased from 0.0017 MeV to include QED calculation errorof 0.0017 MeV (12 ppm).
WEIGHTED AVERAGE
139.57039±0.00017 (Error scaled by 1.6)
Values above of weighted average, error,and scale factor are based upon the data inthis ideogram only. They are not necessarily the same as our ‘best’ values,
obtained from a least-squares constrained fit
utilizing measurements of other (related)
quantities as additional information.

χ
DAUM
19
TRASSINELLI 16
LENZ
98
JECKELMANN 94

2

1.7
4.4
0.4
1.6
8.1
(Confidence Level = 0.045)

139.569

139.57139.571139.572

SPEC
CNTR
CNTR
CNTR

139.573

π ± mass (MeV)

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

m π + − m µ+
Measurements with an error > 0.05 MeV have been omitted from thisListing.
VALUE (MeV)EVTS

DOCUMENT ID

TECN

CHG

COMMENT• • • We do not use the following data for averages, fits, limits, etc. • • •1 DAUM
33.91157± 0.00067
91 SPEC +π + → µ+ ν
33.9111 ± 0.0011
ABELA
84 SPEC
See DAUM 91
33.925 ± 0.025
BOOTH
70 CNTR +Magnetic spect.
33.881 ± 0.035
145
HYMAN
67 HEBC +K − He1 The DAUM 91 value assumes that m
νµ = 0 and uses our m µ = 105.658389 ± 0.000034
MeV.

(m π + − m π − ) / m average
A test of CPT invariance.
VALUE (units 10−4 )DOCUMENT ID

2± 5

AYRES

TECN

71

CNTR

π ± MEAN LIFE
Measurements with an error > 0.02 × 10−8 s have been omitted.
VALUE (10−8 s)

DOCUMENT ID

TECN

CHG

COMMENT

2.6033 ± 0.0005 OUR AVERAGE Error includes scale factor of 1.2.
1 KOPTEV
2.60361± 0.00052
95 SPEC +Surface µ+ ’s
2.60231± 0.00050 ± 0.00084
NUMAO
95 SPEC +Surface µ+ ’s
2.609 ± 0.008
DUNAITSEV 73 CNTR +2.602 ± 0.004
AYRES
71 CNTR ±2.604 ± 0.005
NORDBERG 67 CNTR +2.602 ± 0.004
ECKHAUSE
65 CNTR +• • • We do not use the following data for averages, fits, limits, etc. • • •2 KINSEY
2.640 ± 0.008
66 CNTR +1 KOPTEV 95 combines the statistical and systematic errors; the statistical error dominates.
2 Systematic errors in the calibration of this experiment are discussed by NORDBERG 67.

(τ π + − τ π − ) / τ average
A test of CPT invariance.
VALUE (units 10−4 )DOCUMENT ID

TECN

5.5± 7.1
AYRES
71 CNTR• • • We do not use the following data for averages, fits, limits, etc. • • •− 14 ± 29
40 ± 70
23 ± 40https://pdg.lbl.gov

PETRUKHIN 68
BARDON66
1 LOBKOWICZ 66

Page 3

CNTR
CNTR
CNTR

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

1 This is the most conservative value given by LOBKOWICZ 66.

π ELECTRIC POLARIZABILITY απ
See HOLSTEIN 14 for a general review on hadron polarizability.
VALUE (10−4 fm3 )EVTS

DOCUMENT ID

TECN

1 ADOLPH

2.0± 0.6± 0.7
63k
15A SPEC
1 Value is derived assuming α = −β .
ππCOMMENTπ − γ → π − γ Compton scatt.

π + DECAY MODES
π − modes are charge conjugates of the modes below.
For decay limits to particles which are not established, see the section on
Searches for Axions and Other Very Light Bosons.

Mode

Fraction (Γi /Γ)Confidence level

Γ1
Γ2
Γ3
Γ4
Γ5
Γ6
Γ7
Γ8

µ+ νµ
µ+ νµ γe + νee + νe γ+e νe π 0e + νe e + e −µ+ νµ ν ν
e + νe ν ν

Γ9
Γ10
Γ11

Lepton Family number (LF ) or Lepton number (L) violating modesµ+ ν eL[c] < 1.5
× 10−3 90%µ+ νe
LF[c] < 8.0
× 10−3 90%−++µ e e νLF
< 1.6
× 10−6 90%[a](99.98770± 0.00004) %[b]( 2.00± 0.25[a][b]( 1.230( 7.39± 0.004± 0.05( 1.036( 3.2± 0.006± 0.5) × 10−4) × 10−4) × 10−7< 9) × 10−8) × 10−9
× 10−690%< 1.6

× 10−790%[a] Measurements of Γ(e + νe )/Γ(µ+ νµ ) always include decays with γ’s, andmeasurements of Γ(e + νe γ) and Γ(µ+ νµ γ) never include low-energy γ’s.
Therefore, since no clean separation is possible, we consider the modes
with γ’s to be subreactions of the modes without them, and let [Γ(e + νe )+ Γ(µ+ νµ )]/Γtotal = 100%.
[b] See the Particle Listings below for the energy limits used in this measurement; low-energy γ’s are not included.
[c] Derived from an analysis of neutrino-oscillation experiments.

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

π + BRANCHING RATIOSΓ e + νe /Γtotal

Γ3 /Γ
+See note [a] in the list of π decay modes just above, and see also the next block ofdata. See also the note on “Decay Constants of Charged Pseudoscalar Mesons” in the
D + Listings.
s
VALUE (units 10−4 )DOCUMENT ID

1.230± 0.004 OUR EVALUATION


 


Γ e + νe + Γ e + νe γ / Γ µ+ νµ + Γ µ+ νµ γ

(Γ3 +Γ4 )/(Γ1 +Γ2 )+See note [a] in the list of π decay modes above. See NUMAO 92 for a discussionof e-µ universality. See also the note on “Decay Constants of Charged Pseudoscalar
Mesons” in the D + Listings.
s
VALUE (units 10−4 )EVTS

DOCUMENT ID

TECN

CHG

COMMENT

1.2327± 0.0023 OUR AVERAGE
1.2344± 0.0023 ± 0.0019 400k
AGUILAR-AR...15 CNTR +Stopping π +1.2346± 0.0035 ± 0.0036 120k
CZAPEK
93 CALO
Stopping π +1.2265± 0.0034 ± 0.0044 190k
BRITTON
92 CNTR
Stopping π +1.218 ± 0.014
32k
BRYMAN
86 CNTR
Stopping π +• • • We do not use the following data for averages, fits, limits, etc. • • •1 DICAPUA
1.273 ± 0.028
11k
64 CNTR
1.21 ± 0.07
ANDERSON 60 SPEC
1 DICAPUA 64 has been updated using the current mean life.

Γ µ+ νµ γ /Γtotal

Γ2 /Γ

Note that measurements here do not cover the full kinematic range.

VALUE (units 10−4 )EVTS

DOCUMENT ID

TECN

CHG

COMMENT

1 BRESSI

2.0 ± 0.24±
0.24 ± 0.08
98 CALO +Stopping π +• • • We do not use the following data for averages, fits, limits, etc. • • •1.24± 0.25

26

CASTAGNOLI 58

EMUL

KEµ < 3.38 MeV

1 BRESSI 98 result is given for E

γ > 1 MeV only. Result agrees with QED expectation,−42.283 × 10
and does not confirm discrepancy of earlier experiment CASTAGNOLI 58.

Γ e + νe γ /Γtotal

Γ4 /Γ
The very different values reflect the very different kinematic ranges covered (bigger
range, bigger value). And none of them covers the whole kinematic range.

VALUE (units 10−8 )EVTS

DOCUMENT ID

TECNCOMMENT1 BYCHKOV

73.86± 0.54
65k
09 PIBE e + ν γ at rest• • • We do not use the following data for averages, fits, limits, etc. • • •2 BOLOTOV
16.1 ± 2.3
90B SPEC 17 GeV π − → e − ν e γ
3 STETZ
5.6 ± 0.7
226
78 SPEC Pe > 56 MeV/c
3.0
143
DEPOMMIER 63B CNTR (KE) + > 48 MeV
e γ
1 This BYCHKOV 09 value is for E > 10 MeV and Θ◦> 40 .
γe+ γ
2 BOLOTOV 90B is for E > 21 MeV, E > 70 − 0.8 E .
γeγ
3 STETZ 78 is for an e − γ opening angle > 132◦ . Obtains 3.7 when using same cutoffs
as DEPOMMIER 63B.

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)Γ e + νe π 0 /Γtotal

VALUE (units 10−8 )

Γ5 /Γ

EVTS

DOCUMENT ID

TECN

CHG

COMMENT

1.036± 0.006 OUR AVERAGE
1,2 POCANIC
1.036± 0.006
64k
04 PIBE +π decay at rest
3 MCFARLANE 85 CNTR +1.026± 0.039
1224
Decay in flight+ 0.081.00 −
332
DEPOMMIER 68 CNTR +0.10
4 BACASTOW 65 OSPK +1.07 ± 0.21
38
4
1.10 ± 0.26
BERTRAM65 OSPK +4 DUNAITSEV 65 CNTR +1.1 ± 0.2
43
4 BARTLETT
0.97 ± 0.20
3664 OSPK +• • • We do not use the following data for averages, fits, limits, etc. • • •4 DEPOMMIER 63 CNTR +1.15 ± 0.22
52
See DEPOMMIER 68
1 POCANIC 04 normalizes to e + ν decays, using the PDG 2004 value B(π + → e + ν )ee= (1.230 ± 0.004) × 10−4 . We add their statistical (0.004 × 10−8 ), systematic (0.004 ×
10−8 ) and systematic error due to the uncertainty of B(π + → e + νe ) (0.003 × 10−8 )in quadrature.
2 This result can be used to calculate V
P IBET A = 0.9728 ±ud from pion beta decay: Vud
0.0030.
3 MCFARLANE 85 combines a measured rate (0.394 ± 0.015)/s with 1982 PDG meanlife.
4 DEPOMMIER 68 says the result of DEPOMMIER 63 is at least 10% too large becauseof a systematic error in the π 0 detection efficiency, and that this may be true of all theprevious measurements (also V. Soergel, private communication, 1972).

Γ e + νe e + e − /Γ µ+ νµ
VALUE (units 10−9 )

CL%

EVTS

3.2 ± 0.5 ± 0.2

98Γ6 /Γ1
DOCUMENT ID

EGLI

TECN

89

COMMENT

SPEC

Uses RPCAC =0.068 ± 0.004• • • We do not use the following data for averages, fits, limits, etc. • • •1 BARANOV
0.46± 0.16 ± 0.07
7
92 SPEC Stopped π +< 4.8
90KORENCHE... 76B SPEC
<34
90
KORENCHE... 71 OSPK
1 This measurement by BARANOV 92 is of the structure-dependent part of the decay.
The value depends on values assumed for ratios of form factors.

Γ µ+ νµ ν ν /Γ µ+ νµ
VALUE

CL%

EVTS

DOCUMENT ID<8.6 × 10−6

90

9.1M

AGUILAR-AR...20A SPEC
Γ e + νe ν ν /Γtotal
VALUE

CL%

Γ7 /Γ1TECNCOMMENT

fit E µ spectrum

Γ8 /Γ
EVTS

DOCUMENT ID

TECNCOMMENT<1.6 × 10−790
1.3M
AGUILAR-AR...20A SPEC fit E e spectrum• • • We do not use the following data for averages, fits, limits, etc. • • •<5 × 10−690
PICCIOTTO 88 SPECΓ µ+ ν e /Γtotal

Γ9 /Γ
Forbidden by total lepton number conservation. See the note on “Decay Constants ofCharged Pseudoscalar Mesons” in the D + Listings.
s

VALUE (units 10−3 )

CL%

<1.5

90

https://pdg.lbl.gov

DOCUMENT ID

1 COOPER

Page 6TECN

82COMMENTHLBC Wideband ν beamCreated: 7/25/2024 17:21

Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

1 COOPER 82 limit on ν observation is here interpreted as a limit on lepton numbereviolation.

Γ µ+ νe /Γtotal

Γ10 /Γ

Forbidden by lepton family number conservation.

VALUE (units 10−3 )CL%

DOCUMENT ID

TECNCOMMENT

1 COOPER<8.0
90
82 HLBC Wideband ν beam
1 COOPER 82 limit on ν observation is here interpreted as a limit on lepton family numbereviolation.

Γ µ− e + e + ν /Γtotal

Γ11 /Γ

Forbidden by lepton family number conservation.

VALUE (units 10−6 )CL%

DOCUMENT ID

TECN

CHG

<1.6
90
BARANOV
91B SPEC +• • • We do not use the following data for averages, fits, limits, etc. • • •
<7.7

90

KORENCHE... 87

SPEC

+

π + — POLARIZATION OF EMITTED µ+
π + → µ+ νTests the Lorentz structure of leptonic charged weak interactions.
VALUE

CL%

DOCUMENT ID

TECN

CHG

COMMENT• • • We do not use the following data for averages, fits, limits, etc. • • •1 FETSCHER<(− 0.9959)
90
84 RVUE +2− 0.99± 0.16
ABELA
83 SPEC −µ X-rays
1 FETSCHER 84 uses only the measurement of CARR 83.
2 Sign of measurement reversed in ABELA 83 to compare with µ+ measurements.

See the related review(s):Form Factors for Semileptonic Kaon (Kℓ3 ), Radiative Pion (πℓ 2γ )and Kaon (Kℓ 2γ ) Decays
π ± FORM FACTORSFV , VECTOR FORM FACTOR
VALUE

EVTS

DOCUMENT ID

TECNCOMMENT

0.0254± 0.0017 OUR AVERAGE
1 BYCHKOV
0.0258± 0.0017
65k
09 PIBE e + ν γ at rest20.014 ± 0.009
BOLOTOV
90B SPEC 17 GeV π − → e − ν e γ+ 0.015
0.023 −98
EGLI
89 SPEC π + → e + νe e + e −0.013
1 The BYCHKOV 09 F and F results are highly (anti-)correlated: F + 1.0286 F
AV
AV= 0.03853 ± 0.00014.
2 BOLOTOV 90B only determines the absolute value.

FA , AXIAL-VECTOR FORM FACTOR
VALUE

0.0119± 0.0001

https://pdg.lbl.gov

EVTS

65k

DOCUMENT ID

1,2 BYCHKOV

Page 709

TECN

COMMENTPIBE

e + ν γ at rest

Created: 7/25/2024 17:21

Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)• • • We do not use the following data for averages, fits, limits, etc. • • •1,3 FRLEZ
0.0115± 0.0004
41k
04 PIBE π + → e + ν γ at rest
1,4 BOLOTOV
0.0106± 0.0060
90B SPEC 17 GeV π − → e − ν e γ+ 0.0110.021 −98
EGLI
89 SPEC π + → e + νe e + e −0.013
1,4 BAY
0.0135± 0.0016
86 SPEC π + → e + ν γ
1,4 PIILONEN
0.006 ± 0.003
86 SPEC π + → e + ν γ
1,4,5
0.011 ± 0.003
STETZ
78 SPEC π + → e + ν γ
1 These values come from fixing the vector form factor at the CVC prediction, F =V
0.0259 ± 0.0005.
2 When F is released, the BYCHKOV 09 F is 0.0117 ± 0.0017, and F and F results
VAA
V
are highly (anti-)correlated: FA + 1.0286 FV = 0.03853 ± 0.00014.
3 The sign of γ = F /F is determined to be positive.
AV
4 Only the absolute value of F is determined.
A
5 The result of STETZ 78 has a two-fold ambiguity. We take the solution compatible withlater determinations.

VECTOR FORM FACTOR SLOPE PARAMETER a
This is a in FV (q2 ) = FV (0) (1 + a q2 )

VALUE

EVTS

DOCUMENT ID

0.10± 0.06

65k

BYCHKOV09

TECN

COMMENTPIBE

e + ν γ at rest

TECN

COMMENTSPEC

π + → e + νe e + e −R, SECOND AXIAL-VECTOR FORM FACTOR
VALUE

EVTS

+ 0.0090.059 −
0.008

98

DOCUMENT ID

EGLI

89

π ± CHARGE RADIUSq
r2 is defined in relation to the form
The charge radius of the pionπfactor of the pion electromagnetic vertex, called vector form factor VFF,
FV . The VFF is a function of the squared four-momentum transfer t,π
or of the squared c.m. energy s, depending on the channel in which thephoton exchange takes place. In both cases, it is related to the slope of
the VFF at zero, namely
V (q)
dF π
r2 = 6(q=0) where q = t, s.
πdq
The quantity cannot be measured directly. It can be extracted from thecross sections of three processes: pion electroproduction, e N → e N π,
and pion electron scattering e π → e π, for the t channel, and positronelectron annihilation into two charged pions, e + e − → π + π − , for the schannel. We encode all measurements, but we do not use electroproduction data in averaging because the extraction of the pion radius involves,in this case, theoretical uncertainties that cannot be controlled at theneeded level of accuracy. In case of analyses based on the same dataset, as ANANTHANARAYAN 17 and COLANGELO 19, which cannot beaveraged, we combine the results into a common value, with the uncertainty range chosen to cover both analyses. Note that for consistency
the form factor needs to be defined in both channels with the vacuum
polarisation removed. For details see COLANGELO 19 or Appendix B of
ANANTHANARAYAN 16A.

https://pdg.lbl.gov

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

VALUE (fm)DOCUMENT ID

TECNCOMMENT

0.659 ± 0.004 OUR AVERAGE
1 PDG
0.656 ± 0.005
19 FIT
0.65 ± 0.05 ± 0.06
ESCHRICH
01 CNTR π e → π e
0.663 ± 0.006
AMENDOLIA 86 CNTR π e → π e
0.663 ± 0.023
DALLY
82 CNTR π e → π e• • • We do not use the following data for averages, fits, limits, etc. • • •2 CUI
0.640 ± 0.007
21A FITFit existing data
30.655 ± 0.004
COLANGELO 19 FIT
Fit existing data
4 ANANTHANA...17 FIT
0.657 ± 0.003
Fit existing data
5 HANHART
0.6603± 0.0005 ± 0.0004
17 FITFit existing data
60.740 ± 0.031
LIESENFELD 99 CNTR e p → e π + n70.661 ± 0.012
BIJNENS
98 CNTR χPT extraction
0.660 ± 0.024
AMENDOLIA 84 CNTR π e → π e
6 BEBEK
0.711 ± 0.009 ± 0.016
78 CNTR e N → e π N
8 QUENZER
0.678 ± 0.004 ± 0.008
78 CNTR e + e − → π + π −+ 0.090.78 −ADYLOV
77 CNTR π e → π e
0.10+ 0.110.74 −BARDIN
77 CNTR e p → e π + n
0.13
0.56 ± 0.04
DALLY
77 CNTR π e → π e
1 This value combines the measurements of ANANTHANARAYAN 17 and COLANGELO 19 which are based on the same data set. The uncertainty range is chosen
to cover both results.
2 CUI 21A perform a fit including spacelike data only. Employ a new mathematical procedure based on interpolation via continued fractions augmented by statistical sampling.
Also do not impose the charge conserving normalization condition F(0) = 1.
3 COLANGELO 19 fit existing F data, using an extended Omnes dispersive representaVtion. This analysis is based on the same data set of ANANTHANARAYAN 17 . Accordingly, they cannot be averaged. We combine the results into a common value, with theuncertainty range chosen to cover the uncertainty ranges of both analyses.
4 ANANTHANARAYAN 17 fit existing F data, using a mixed phase-modulus dispersiveV
representation. This analysis is based on the same data set of COLANGELO 19. Accordingly, they cannot be averaged. We combine the results into a common value, withthe uncertainty range chosen to cover the uncertainty ranges of both analyses.
5 According to the authors the uncertainty could be underestimated. The value quotedomits the BaBar data AUBERT 09.
6 The extractions could contain an additional theoretical uncertainty which cannot be
sufficiently quantified.
7 BIJNENS 98 fits existing data.
8 The extraction is based on a parametrization that does not have correct analytic properties.

π ± REFERENCES
We have omitted some papers that have been superseded by later experiments. The omitted papers may be found in our 1988 edition Physics
Letters B204 1 (1988).
CUI
21A
AGUILAR-AR... 20A
COLANGELO 19
DAUM
19
PDG
19
ANANTHANA...17

PL B822 136631
PR D102 012001
JHEP 1902 006
PL B796 11
RPP 2019 at pdg.lbl.gov
PRL 119 132002

https://pdg.lbl.gov

Z.-F. Cui et al.
(NJU, ECT, HZDR)
A. Aguilar-Arevalo et al.
(PIENU Collab.)
G. Colangelo, M. Hoferichter, P. Stoffer(BERN+)
M. Daum, R. Frosch, P.-R. Kettle(PSI)
M. Tanabashi et al.
(PDG Collab.)
B. Ananthanarayan, I. Caprini, D. Das

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HANHART
17
ANANTHANA...16A
TRASSINELLI 16
ADOLPH
15A
AGUILAR-AR... 15
HOLSTEIN
14
AUBERT
09
BYCHKOV
09
FRLEZ
04
POCANIC04
ESCHRICH
01
LIESENFELD 99
BIJNENS98
BRESSI98
LENZ
98
ASSAMAGAN 96
KOPTEV
95
NUMAO
95
ASSAMAGAN 94
JECKELMANN 94
CZAPEK93
BARANOV92
BRITTONAlso
NUMAO
BARANOV92

DAUM
BOLOTOV
EGLI
Also
PDG
PICCIOTTO
COHEN
KORENCHE...

91
90B
89

92
91B

88
88
87
87

AMENDOLIA 86
BAY86
BRYMAN86
Also
JECKELMANN 86B
Also
PIILONEN86MCFARLANE 85
ABELA
84
Also
Also
AMENDOLIA 84
FETSCHER
84
ABELA
83
CARR
83
COOPER
82
DALLY
82
LU
80
BEBEK
78
QUENZER
78
STETZ
78
ADYLOV77
BARDIN
77
DALLY
77
CARTER76
KORENCHE... 76B
MARUSHEN... 76
Also
Also
DUNAITSEV73

EPJ C77 98
C. Hanhart et al.
PR D93 116007
B. Ananthanarayan et al.
PL B759 583
M. Trassinelli et al.
PRL 114 062002
C. Adolph et al.
(COMPASS Collab.)
PRL 115 071801
A. Aguilar-Arevalo et al.
(PIENU Collab.)
ARNPS 64 51
B. Holstein, S. Scherer(MASA, MAINZ)PR D79 011102
B. Aubert et al.
(BABAR Collab.)
PRL 103 051802
M. Bychkov et al.
(PSI PIBETA Collab.)
PRL 93 181804
E. Frlez et al.
(PSI PIBETA Collab.)
PRL 93 181803
D. Pocanic et al.
(PSI PIBETA Collab.)
PL B522 233
I. Eschrich et al.
(FNAL SELEX Collab.)
PL B468 20
A. Liesenfeld et al.
JHEP 9805 014
J. Bijnens et al.
NP B513 555
G. Bressi et al.
PL B416 50
S. Lenz et al.
PR D53 6065
K.A. Assamagan et al.
(PSI, ZURI, VILL+)JETPL 61 877
V.P. Koptev et al.
(PNPI)
Translated from ZETFP 61 865.
PR D52 4855
T. Numao et al.
(TRIU, BRCO)
PL B335 231
K.A. Assamagan et al.
(PSI, ZURI, VILL+)PL B335 326
B. Jeckelmann, P.F.A. Goudsmit, H.J. Leisi(WABRN+)PRL 70 17
G. Czapek et al.
(BERN, VILL)SJNP 55 1644
V.A. Baranov et al.
(JINR)
Translated from YAF 55 2940.
PRL 68 3000
D.I. Britton et al.
(TRIU, CARL)PR D49 28
D.I. Britton et al.
(TRIU, CARL)MPL A7 3357
T. Numao(TRIU)SJNP 54 790
V.A. Baranov et al.
(JINR)
Translated from YAF 54 1298.
PL B265 425
M. Daum et al.
(VILL)PL B243 308
V.N. Bolotov et al.
(INRM)PL B222 533
S. Egli et al.
(SINDRUM Collab.)
PL B175 97
S. Egli et al.
(AACH3, ETH, SIN, ZURI)PL B204 1
G.P. Yost et al.
(LBL+)
PR D37 1131
C.E. Picciotto et al.
(TRIU, CNRC)
RMP 59 1121
E.R. Cohen, B.N. Taylor(RISC, NBS)SJNP 46 192
S.M. Korenchenko et al.
(JINR)
Translated from YAF 46 313.
NP B277 168
S.R. Amendolia et al.
(CERN NA7 Collab.)
PL B174 445
A. Bay et al.
(LAUS, ZURI)PR D33 1211
D.A. Bryman et al.
(TRIU, CNRC)
PRL 50 7
D.A. Bryman et al.
(TRIU, CNRC)
NP A457 709
B. Jeckelmann et al.
(ETH, FRIB)PRL 56 1444
B. Jeckelmann et al.
(ETH, FRIB)PRL 57 1402
L.E. Piilonen et al.
(LANL, TEMP, CHIC)PR D32 547
W.K. McFarlane et al.
(TEMP, LANL)
PL 146B 431
R. Abela et al.
(SIN)
PL 74B 126
M. Daum et al.
(SIN)
PR D20 2692
M. Daum et al.
(SIN)
PL 146B 116
S.R. Amendolia et al.
(CERN NA7 Collab.)
PL 140B 117
W. Fetscher(ETH)
NP A395 413
R. Abela et al.
(BASL, KARLK, KARLE)
PRL 51 627
J. Carr et al.
(LBL, NWES, TRIU)
PL 112B 97
A.M. Cooper et al.
(RL)
PRL 48 375
E.B. Dally et al.
PRL 45 1066
D.C. Lu et al.
(YALE, COLU, JHU)
PR D17 1693
C.J. Bebek et al.
PL 76B 512
A. Quenzer et al.
(LALO)NP B138 285
A.W. Stetz et al.
(LBL, UCLA)NP B128 461
G.T. Adylov et al.
NP B120 45
G. Bardin et al.
PRL 39 1176
E.B. Dally et al.
PRL 37 1380
A.L. Carter et al.
(CARL, CNRC, CHIC+)JETP 44 35
S.M. Korenchenko et al.
(JINR)
Translated from ZETF 71 69.
JETPL 23 72
V.I. Marushenko et al.
(PNPI)
Translated from ZETFP 23 80.
Private Comm.
R.E. Shafer(FNAL)
Private Comm.
A. Smirnov(PNPI)SJNP 16 292
A.F. Dunaitsev et al.
(SERP)
Translated from YAF 16 524.

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Citation: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)

AYRES
71
Also
Also
Also
Also
KORENCHE... 71
BOOTH
DEPOMMIERPETRUKHIN
HYMAN
NORDBERGBARDONKINSEYLOBKOWICZBACASTOWBERTRAMDUNAITSEV

70
68
68
67
67
66
66
66
65
65
65

ECKHAUSEBARTLETTDICAPUA
Also
DEPOMMIER
DEPOMMIER
ANDERSONCASTAGNOLI

65
64
64
63
63B
60
58

PR D3 1051
D.S. Ayres et al.
(LRL, UCSB)PR 157 1288
D.S. Ayres et al.
(LRL)
PRL 21 261
D.S. Ayres et al.
(LRL, UCSB)
Thesis UCRL 18369
D.S. Ayres(LRL)
PRL 23 1267
A.J. Greenberg et al.
(LRL, UCSB)SJNP 13 189
S.M. Korenchenko et al.
(JINR)
Translated from YAF 13 339.
PL 32B 723
P.S.L. Booth et al.
(LIVP)NP B4 189
P. Depommier et al.
(CERN)JINR P1 3862
V.I. Petrukhin et al.
(JINR)PL 25B 376
L.G. Hyman et al.
(ANL, CMU, NWES)
PL 24B 594
M.E. Nordberg, F. Lobkowicz, R.L. Burman(ROCH)
PRL 16 775
M. Bardon et al.
(COLU)PR 144 1132
K.F. Kinsey, F. Lobkowicz, M.E. Nordberg(ROCH)
PRL 17 548
F. Lobkowicz et al.
(ROCH, BNL)PR 139 B407
R.B. Bacastow et al.
(LRL, SLAC)PR 139 B617
W.K. Bertram et al.
(MICH, CMU)JETP 20 58
A.F. Dunaitsev et al.
(JINR)
Translated from ZETF 47 84.
PL 19 348
M. Eckhause et al.
(WILL)PR 136 B1452
D. Bartlett et al.
(COLU)PR 133 B1333
M. di Capua et al.
(COLU)
Private Comm.
L. Pondrom(WISC)PL 5 61
P. Depommier et al.
(CERN)PL 7 285
P. Depommier et al.
(CERN)PR 119 2050
H.L. Anderson et al.
(EFI)
PR 112 1779
C. Castagnoli, M. Muchnik(ROMA)

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Page 11Created: 7/25/2024 17:21