Journal Article

IMPULSE-2021-00175

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Limit on the Fierz Interference Term b from a Measurement of the Beta Asymmetry in Neutron Decay

Saul, H.MLZ* ; Roick, C. ; Abele, H. ; Mest, H. ; Klopf, M. ; Petukhov, A. K. ; Soldner, T. ; Wang, X.MLZ* ; Werder, D. ; Maerkisch, B.MLZ*

2020
APS College Park, Md.

Please use a persistent id in citations: doi:10.1103/PhysRevLett.125.112501

Abstract: In the standard model of particle physics, the weak interaction is described by vector and axial-vector couplings only. Nonzero scalar or tensor interactions would imply an additional contribution to the differential decay rate of the neutron, the Fierz interference term. We derive a limit on this hypothetical term from a measurement using spin-polarized neutrons. This method is statistically less sensitive than the determination from the spectral shape but features much cleaner systematics. We obtain a limit of b=0.017(21) at 68.27% C.L., improving the previous best limit from neutron decay by a factor of four.

Keyword(s): Nuclei and Particles (1st) ; Particle Physics (2nd)

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Contributing Institute(s):

1. E18 (E18)
2. MLZ (MLZ)

Experiment(s):

1. MEPHISTO: Facility for particle physics with cold neutrons (SR4b)

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Electronics and Telecommunications Collection ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; Nationallizenz ; SCOAP3 sponsored Journal ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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