Journal Article

IMPULSE-2021-00176

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Accurate Measurement of the Beta-Asymmetry in Neutron Decay Rules out Dark Decay Mode

Maerkisch, B.MLZ* ; Abele, H. ; Dubbers, D. ; Saul, H.MLZ* ; Soldner, T.

2020
Springer Science+Business Media Berlin

Please use a persistent id in citations: doi:10.1134/S1027451020070319

Abstract: The question of the nature of dark matter is one of the major challenges of elementary particle physics. Not surprisingly, the recent suggestion of a dark decay channel as a solution to persisting discrepancies in neutron lifetime measurements has initiated substantial research activity. We discuss the accurate measurement of the parity violating β-asymmetry using Perkeo III. The result is about five times more precise than the current world average and resolves a long-standing discrepancy. Based on this, we largely rule out the dark decay mode interpretation. We derive a new world average of the weak axial coupling and obtain a competitive value of the first element of the quark mixing matrix Vud from neutron decay.

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 ; DEAL Springer ; Emerging Sources Citation Index ; SCOPUS ; Web of Science Core Collection

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