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Title: Light, long-lived B − L gauge and Higgs bosons at the DUNE near detector
The low-energy U(1)B−L gauge symmetry is well-motivated as part of beyond Standard Model physics related to neutrino mass generation. We show that a light B − L gauge boson Z′ and the associated U(1)B−L-breaking scalar φ can both be effectively searched for at high-intensity facilities such as the near detector complex of the Deep Underground Neutrino Experiment (DUNE). Without the scalar φ, the Z′ can be probed at DUNE up to mass of 1GeV, with the corresponding gauge coupling gBL as low as 10−9 . In the presence of the scalar φ with gauge coupling to Z ′ , the DUNE capability of discovering the gauge boson Z′ can be significantly improved, even by one order of magnitude in gBL, due to additional production from the decay φ → Z′Z′. The DUNE sensitivity is largely complementary to other long-lived Z′ searches at beam-dump facilities such as FASER and SHiP, as well as astrophysical and cosmological probes. On the other hand, the prospects of detecting φ itself at DUNE are to some extent weakened in presence of Z′, compared to the case without the gauge interaction.  more » « less
Award ID(s):
1914731
NSF-PAR ID:
10354000
Author(s) / Creator(s):
Date Published:
Journal Name:
JHEP reports
Volume:
07 (2021) 166
Issue:
07
ISSN:
2589-5559
Page Range / eLocation ID:
166
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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