Observation of Enhanced Long-Range Elliptic Anisotropies Inside High-Multiplicity Jets in pp Collisions at √s=13 TeV
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Tarih
2024
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Physical Soc
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
A search for collective effects inside jets produced in proton-proton collisions is performed via correlation measurements of charged particles using the CMS detector at the CERN LHC. The analysis uses data collected at a center-of-mass energy of root s = 13 TeV, corresponding to an integrated luminosity of 138 fb(-1). Jets are reconstructed with the anti-kT algorithm with a distance parameter of 0.8 and are required to have transverse momentum greater than 550 GeV and pseudorapidity vertical bar eta(jet)vertical bar < 1.6. Two-particle correlations among the charged particles within the jets are studied as functions of the particles' azimuthal angle and pseudorapidity separations (Delta phi* and Delta eta*) in a jet coordinate basis, where particles' eta*, phi* are defined relative to the direction of the jet. The correlation functions are studied in classes of in-jet chargedparticle multiplicity up to N-ch(J) approximate to 100. Fourier harmonics are extracted from long-range azimuthal correlation functions to characterize azimuthal anisotropy for vertical bar Delta eta*vertical bar > 2. For low-N-ch(j) jets, the long-range elliptic anisotropic harmonic, v(2)*, is observed to decrease with N-ch(j). This trend is well described by Monte Carlo event generators. However, a rising trend for v(2)* emerges at N-ch(j) greater than or similar to 80, hinting at a possible onset of collective behavior, which is not reproduced by the models tested. This observation yields new insights into the dynamics of jet evolution in the vacuum.
Açıklama
Anahtar Kelimeler
Plus Au Collisions
Kaynak
Physical Review Letters
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
133
Sayı
14
