Gamma-induced background in the KATRIN main spectrometer
Creators: name: Altenmüller, K.
name: Arenz, M.
name: Baek, W. -J.
name: Beck, M.
name: Beglarian, A.
name: Behrens, J.
name: Berlev, A.
name: Besserer, U.
name: Blaum, K.
name: Block, F.
name: Bobien, S.
name: Bode, T.
name: Bornschein, B.
name: Bornschein, L.
name: Bouquet, H.
name: Brunst, T.
name: Buzinsky, N.
name: Chilingaryan, S.
name: Choi, W. Q.
name: Deffert, M.
name: Doe, P. J.
name: Dragoun, O.
name: Drexlin, G.
name: Dyba, S.
name: Eitel, K.
name: Ellinger, E.
name: Engel, R.
name: Enomoto, S.
name: Erhard, M.
name: Eversheim, D.
name: Fedkevych, M.
name: Formaggio, J. A.
name: Fränkle, F. M.
name: Franklin, G. B.
name: Friedel, F.
name: Fulst, A.
name: Gil, W.
name: Glück, F.
name: Ureña, A. Gonzalez
name: Grössle, R.
name: Gumbsheimer, R.
name: Hackenjos, M.
name: Hannen, V.
name: Harms, F.
name: Haußmann, N.
name: Heizmann, F.
name: Helbing, K.
name: Herz, W.
name: Hickford, S.
name: Hilk, D.
name: Hillesheimer, D.
name: Howe, M. A.
name: Huber, A.
name: Jansen, A.
name: Karl, C.
name: Kellerer, J.
name: Kernert, N.
name: Kippenbrock, L.
name: Klein, M.
name: Kopmann, A.
name: Korzeczek, M.
name: Kovalík, A.
name: Krasch, B.
name: Kraus, A.
name: Kraus, M.
name: Lasserre, T.
name: Lebeda, O.
name: Lehnert, B.
name: Letnev, J.
name: Lokhov, A.
name: Machatschek, M.
name: Marsteller, A.
name: Martin, E. L.
name: Mertens, S.
name: Mirz, S.
name: Monreal, B.
name: Neumann, H.
name: Niemes, S.
name: Osipowicz, A.
name: Otten, E.
name: Parno, D. S.
name: Pollithy, A.
name: Poon, A. W. P.
name: Priester, F.
name: Ranitzsch, P. C. -O.
name: Rest, O.
name: Robertson, R. G. H.
name: Rodenbeck, C.
name: Röllig, M.
name: Röttele, C.
name: Ryšavý, M.
name: Sack, R.
name: Saenz, A.
name: Schimpf, L.
name: Schlösser, K.
name: Schlösser, M.
name: Schlüter, L.
name: Schrank, M.
name: Seitz-Moskaliuk, H.
name: Sibille, V.
name: Slezák, M.
name: Steidl, M.
name: Steinbrink, N.
name: Sturm, M.
name: Suchopar, M.
name: Tcherniakhovski, D.
name: Telle, H. H.
name: Thorne, L. A.
name: Thümmler, T.
name: Titov, N.
name: Tkachev, I.
name: Trost, N.
name: Valerius, K.
name: Vénos, D.
name: Vianden, R.
name: Hernández, A. P. Vizcaya
name: Weber, M.
name: Weinheimer, C.
name: Weiss, C.
name: Welte, S.
name: Wendel, J.
name: Wilkerson, J. F.
name: Wolf, J.
name: Wüstling, S.
name: Zadoroghny, S.
name: Zeller, G.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The KATRIN experiment aims to measure the effective electron antineutrino mass $m_{\overlineν_e}$ with a sensitivity of 0.2 eV/c$^2$ using a gaseous tritium source combined with the MAC-E filter technique. A low background rate is crucial to achieving the proposed sensitivity, and dedicated measurements have been performed to study possible sources of background electrons. In this work, we test the hypothesis that gamma radiation from external radioactive sources significantly increases the rate of background events created in the main spectrometer (MS) and observed in the focal-plane detector. Using detailed simulations of the gamma flux in the experimental hall, combined with a series of experimental tests that artificially increased or decreased the local gamma flux to the MS, we set an upper limit of 0.006 count/s (90% C.L.) from this mechanism. Our results indicate the effectiveness of the electrostatic and magnetic shielding used to block secondary electrons emitted from the inner surface of the MS.