English

Anomalies in Bottom from new physics in Top

High Energy Physics - Phenomenology 2018-08-07 v2

Abstract

We analyze the possibility to accommodate current bs+b \to s \ell^+ \ell^- anomalies with TeV-scale mediators that couple to right-handed top quarks and muons, contributing to bs+b \to s \ell^+ \ell^-\, at the one-loop level. We use the Standard Model Effective Field Theory (SMEFT) framework but also look at specific scenarios by taking into account all possible irreducible representations of the Lorentz and Standard Model gauge group for the mediators. From a global fit of bs+b \to s \ell^+ \ell^- data and LEP-I observables we find that the Wilson coefficients of two SMEFT operators: Ou=(ˉLμγαLμ)(tˉRγαtR)\mathcal{O}_{\ell u}= (\bar \ell_{ L \mu} \gamma^{\alpha} \ell_{ L \mu}) (\bar t_R \gamma_{\alpha} t_R ) and Oeu=(μˉRγαμR)(tˉRγαtR)\mathcal{O}_{e u}= (\bar \mu_{R} \gamma^{\alpha} \mu_{R}) (\bar t_R \gamma_{\alpha} t_R ) need to satisfy CeuCu\mathcal{C}_{eu} \sim \mathcal{C}_{\ell u}. New physics enters then in bs+b \to s \ell^+ \ell^- mainly through the operator O9=(sˉγμPLb)(ˉγμ)\mathcal{O}_9 = ( \bar s \gamma_{\mu} P_{L} b )( \bar \ell \gamma^{\mu} \ell ) of the Weak Effective Theory. After discussing all possible mediators, we concentrate on two scenarios: A vector boson in the irreducible representation Zμ(1,1,0)Z_{\mu}^{\prime} \sim (1,1,0) of the Standard Model gauge group with vectorial coupling to muons, and a combination of two leptoquarks: the scalar R2(3,2,7/6)R_2 \sim (3,2,7/6) and the vector U~1μ(3,1,5/3)\widetilde U_{1 \mu} \sim (3,1,5/3). We derive LHC constraints by recasting di-muon resonance, ppttˉttˉpp \to t \bar t t \bar t and SUSY searches. Additionally, we analyze the prospects for discovering these mediators during the high-luminosity phase of the LHC.

Keywords

Cite

@article{arxiv.1805.04917,
  title  = {Anomalies in Bottom from new physics in Top},
  author = {José Eliel Camargo-Molina and Alejandro Celis and Darius A. Faroughy},
  journal= {arXiv preprint arXiv:1805.04917},
  year   = {2018}
}

Comments

13 pages, 10 figures, 4 tables -- v2: Overview section removed, added Table IV, added B meson mixing discussion, added refs, version accepted for publication in Phys. Lett. B

R2 v1 2026-06-23T01:53:23.129Z