Naslov
Observation of a New Excited Beauty Strange Baryon Decaying to Ξ−bπ+π−

Autori
Sirunyan, Albert M ; ... ; Antunović, Željko ; Brigljević, Vuko ; Ferenček, Dinko ; Giljanović, Duje ; Godinović, Nikola ; Kovač, Marko ; Lelas, Damir ; Majumder, Devdatta ; Puljak, Ivica ; Roguljić, Matej ; Starodumov, Andrey ; Đurić, Senka ; Šuša, Tatjana ; Šćulac, Toni ; ... ; Vetens, Wren

Kolaboracija
CMS Collaboration

Izvornik
Physical review letters (0031-9007) 126 (2021), 25; 252003, 19

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
High energy physics ; Experimental particle physics ; LHC ; CMS ; Radiation-hard detectors ; Si microstrip and pad detectors ; Radiation damage to detector materials (solid state) ; Particle tracking detectors (Solid-state detectors) ; radiation: damage ; CMS: upgrade ; tracking detector ; semiconductor detector: design ; semiconductor detector: microstrip ; performance ; Hadron-Hadron scattering (experiments) ; Top physics ; p p: scattering ; p p: colliding beams ; top: single production

Sažetak
The Ξ−bπ+π− invariant mass spectrum is investigated with an event sample of proton-proton collisions at √s=13 TeV, collected by the CMS experiment at the LHC in 2016–2018 and corresponding to an integrated luminosity of 140 fb−1. The ground state Ξ−b is reconstructed via its decays to J/ψΞ− and J/ψΛK−. A narrow resonance, labeled Ξb(6100)−, is observed at a Ξ−bπ+π− invariant mass of 6100.3±0.2(stat) ±0.1(syst)±0.6(Ξ−b) MeV, where the last uncertainty reflects the precision of the Ξ−b baryon mass. The upper limit on the Ξb(6100)− natural width is determined to be 1.9 MeV at 95% confidence level. The low Ξb(6100)− signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξc baryon states, the new Ξb(6100)− resonance and its decay sequence are consistent with the orbitally excited Ξ−b baryon, with spin and parity quantum numbers JP=3/2−

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA