Investigation İnto The Event-Activity Dependence Of ?(Ns) Relative Production İn Proton-Proton Collisions At ? S = 7 Tev

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Küçük Resim

Tarih

2020

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

The CMS Collaboration

Erişim Hakkı

Özet

The ratios of the production cross sections between the excited ?(2S) and ?(3S) mesons and the ?(1S) ground state, detected via their decay into two muons, are studied as a function of the number of charged particles in the event. The data are from proton-proton collisions at s?= 7 TeV, corresponding to an integrated luminosity of 4.8 fb?1, collected with the CMS detector at the LHC. Evidence of a decrease in these ratios as a function of the particle multiplicity is observed, more pronounced at low transverse momentum p??T. For ?(nS) mesons with p??T > 7 GeV, where most of the data were collected, the correlation with multiplicity is studied as a function of the underlying event transverse sphericity and the number of particles in a cone around the ?(nS) direction. The ratios are found to be multiplicity independent for jet-like events. The mean p??T values for the ?(nS) states as a function of particle multiplicity are also measured and found to grow more steeply as their mass increases.

Açıklama

Anahtar Kelimeler

High Energy Physics, Experiment (hep-ex)

Kaynak

WoS Q Değeri

N/A

Scopus Q Değeri

Q2

Cilt

Sayı

Künye

JHEP 11 (2020) 001