Search for Hidden-Sector Bosons inB0→K*0μ+μ

Abstract

A search is presented for hidden-sector bosons, χ, produced in the decay B(0)→K*(892)(0)χ, with K*(892)(0)→K(+)π(-) and χ→μ(+)μ(-). The search is performed using pp-collision data corresponding to 3.0 fb(-1) collected with the LHCb detector. No significant signal is observed in the accessible mass range 214≤m(χ)≤4350 MeV, and upper limits are placed on the branching fraction product B(B(0)→K*(892)(0)χ)×B(χ→μ(+)μ(-)) as a function of the mass and lifetime of the χ boson. These limits are of the order of 10(-9) for χ lifetimes less than 100 ps over most of the m(χ) range, and place the most stringent constraints to date on many theories that predict the existence of additional low-mass bosons.

Physics beyond colliders at CERN: beyond the Standard Model working group report

“…Searches for ALPs with fermion coupling are being pursued at the LHC, namely in the analysis of rare B decays as for example B + → K * 0 µ + µ − [243]. The geometry of the LHC experiments, on the other hand, is such that a search can be performed only if the ALP decays more or less instantaneously, hence has large couplings.…”

Probing the Higgs portal at the Fermilab short-baseline neutrino experiments

“…The regions enclosed by solid lines would be probed using our cuts, where we have conservatively assumed that sensitivity will require a minimum signal of 5 events or 100% of the background. We have also indicated, with dashed lines, where 5 events would occur in SBND on light Higgs portal scalars from CHARM [86,87], LHCb [88,89], E787/E949 [87,90] and SN 1987A [91]. Fig.…”

Light gauge boson interpretation for (g − 2)μ and the KL→ π0 + (invisible) anomaly at the J-PARC KOTO experiment

“…5, we show the preferred region of parameters (m X , g X and ) and the current experimental constraints. In model II, we have two allowed regions (120 MeV ∼ < m X ∼ < 160 MeV and 250 MeV ∼ < m X ∼ < 350 MeV) for the KOTO events, although higher mass region cannot explain (g − 2) µ simultaneously, due to the experimental constraints from 4µ search from BaBar [64] and the search of the muonic force coupled to b → sX FCNC vertex at LHCb [65]. In addition to down-type FCNC couplings (g eff dsX | B 3 , g eff sbX | B 3 and g eff dbX | B 3 ) which are proportional to g 2 16π 2 V ti V * tj F 1 (x t ), there are also tree-level up-type (left-handed) FCNC couplings due to SU (2) L gauge invariance as…”