English

$U(1)_{B_3-L_2}$ Explanation of the Neutral Current $B-$Anomalies

High Energy Physics - Phenomenology 2021-03-26 v6 High Energy Physics - Experiment

Abstract

We investigate a speculative short-distance force, proposed to explain discrepancies observed between measurements of certain neutral current decays of BB hadrons and their Standard Model predictions. The force derives from a spontaneously broken, gauged U(1)B3L2U(1)_{B_3-L_2} extension to the Standard Model, where the extra quantum numbers of Standard Model fields are given by third family baryon number minus second family lepton number. The only fields beyond those of the Standard Model are three right-handed neutrinos, a gauge field associated with U(1)B3L2U(1)_{B_3-L_2} and a Standard Model singlet complex scalar which breaks U(1)B3L2U(1)_{B_3-L_2}, a `flavon'. This simple model, via interactions involving a TeV scale force-carrying ZZ^\prime vector boson, can successfully explain the neutral current BB-anomalies whilst accommodating other empirical constraints. In an ansatz for fermion mixing, a combination of up-to-date BB-anomaly fits, LHC direct ZZ^\prime search limits and other bounds rule out the domain 0.15 TeV<MZ<< M_{Z^\prime} < 1.9 TeV at the 95%\% confidence level. For more massive ZZ^\primes, the model possesses a {\em flavonstrahlung}\ signal, where pppp collisions produce a ZZ^\prime and a flavon, which subsequently decays into two Higgs bosons.

Keywords

Cite

@article{arxiv.2009.02197,
  title  = {$U(1)_{B_3-L_2}$ Explanation of the Neutral Current $B-$Anomalies},
  author = {B. C. Allanach},
  journal= {arXiv preprint arXiv:2009.02197},
  year   = {2021}
}

Comments

11 pages, 7 figures, v4 has a discussion of the anomalous magnetic moment of the muon. v3 was version accepted for publication. v4 fixes errors in (21),(22) which makes slight changes to trident bound in Figs. 8,9