Observation of the Ξ⁻b→ψ(2S)Ξ− decay and studies of the Ξb(5945)⁰ baryon in proton-proton collisions at √s = 13  TeV


Date

2024-07-01

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

The first observation of the decay Ξ⁻b → ψ(2S)Ξ⁻ and measurement of the branching ratio of Ξ⁻b → ψ(2S)Ξ⁻ to Ξ⁻b → J/ψΞ⁻ are presented. The J/ψ and ψ(2S) mesons are reconstructed using their dimuon decay modes. The results are based on proton-proton colliding beam data from the LHC collected by the CMS experiment at √s = 13  TeV in 2016–2018, corresponding to an integrated luminosity of 140  fb⁻¹. The branching fraction ratio is measured to be B(Ξ⁻b → ψ(2S)Ξ⁻)/B(Ξ⁻b → J/ψΞ⁻)=0.84⁺⁰.²¹₋₀.₁₉(stat)±0.10(syst)±0.02(B), where the last uncertainty comes from the uncertainties in the branching fractions of the charmonium states. New measurements of the Ξb(5945)0 baryon mass and natural width are also presented, using the Ξ⁻bπ⁺ final state, where the Ξ⁻b baryon is reconstructed through the decays J/ψΞ⁻, ψ(2S)Ξ⁻, J/ψΛK⁻, and J/ψΣ0K⁻. Finally, the fraction of Ξ⁻b baryons produced from Ξb(5945)⁰ decays is determined.

Publication status

published

Editor

Book title

Volume

110 (1)

Pages / Article No.

12002

Publisher

American Physical Society

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Branching fraction; Bottom quark; Hadron colliders

Organisational unit

09720 - de Cosa, Annapaola / de Cosa, Annapaola check_circle
03593 - Dissertori, Günther / Dissertori, Günther check_circle
03904 - Wallny, Rainer / Wallny, Rainer check_circle

Notes

Funding

758316 - Majorana neutrino discovery strategy with CMS (EC)

Related publications and datasets