Search for the radiative $$ {\Xi}_b^{-} $$ → Ξ−γ decay

Abstract

The first search for the rare radiative decay $$ {\Xi}_b^{-} $$ Ξ b − → Ξ−γ is performed using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb−1. The $$ {\Xi}_b^{-} $$ Ξ b − → Ξ−J/ψ channel is used as normalization. No $$ {\Xi}_b^{-} $$ Ξ b − → Ξ−γ signal is found and an upper limit of $$ \mathcal{B} $$ B ($$ {\Xi}_b^{-} $$ Ξ b − → Ξ−γ) < 1.3 × 10−4 at 95% confidence level is obtained.

Experimental status of $b \to s \{\gamma, e^+e^-, \mu^+\mu^-\}$ at the LHC

“…fraction at B (𝛯 𝑏 → 𝛯 0 𝛾) < 1.3 (0.6) × 10 −4 at 95% (90%) confidence level [69]. This limit is somewhat in tension with SM predictions based on light-cone sum rule calculations from Ref.…”

The LHCb Upgrade I

“…The most widely adopted fast-simulation option (see for example refs. [231][232][233][234]) is implemented in the ReDecay package [235]. Once a signal process is identified, for example the production of a heavy hadron, multiple random instances of its decay products are propagated through the detector while the detector response to the rest of the event is computed only once and superposed to the decay products of the signal particle.…”

WG3 Summary -- Rare B, D and K decays

“…An angular analysis of this mode [53,54] allowed recently to measure the photon polarization = 0.82 +0.17 −0.26 +0.04 −0.13 [55], which is in good agreement with the SM prediction. A search for the radiative -baryon decay Ξ − → Ξ − results in an upper limit of B (Ξ − → Ξ − ) < 1.3 × 10 −4 at 95% CL [56].…”