Hayrapetyan, A.Tumasyan, A.Adam, W.Andrejkovic, J. W.Bergauer, T.Chatterjee, S.Zhokin, A.2025-01-102025-01-1020240031-90071079-7114https://doi.org/10.1103/PhysRevLett.133.142301Della Ricca, Giuseppe/0000-0003-2831-6982; Yalvac, Metin/0000-0003-4915-9162; Grunewald, Martin/0000-0002-5754-0388; Borshch, Vladislav/0000-0002-5479-1982; Tuominiemi, Jorma/0000-0003-0386-8633; Martikainen, Laura/0000-0003-1609-3515; Tedeschi, Tommaso/0000-0002-7125-2905; Asenov, Patrick/0000-0003-2379-9903; Garcia, Francisco/0000-0002-4023-7964; Dragicevic, Marko/0000-0003-1967-6783; Lunerti, Leonardo/0000-0002-8932-0283; Milosevic, Vukasin/0000-0002-1173-0696; Schieck, Jochen/0000-0002-1058-8093; Osterberg, Kenneth/0000-0003-4807-0414; Bharthuar, Shudhashil/0000-0001-5871-9622; Hernandez Calama, Jose Maria/0000-0001-6436-7547; Da Cruz E Silva, Cristovao/0000-0002-1231-3819; Hall, Geoffrey/0000-0002-6299-8385; Linden, Tomas/0009-0002-4847-8882; Cipriani, Marco/0000-0002-0151-4439; Giommi, Luca/0000-0003-3539-4313; Siikonen, Hannu/0000-0003-2039-5874; Moscatelli, Francesco/0000-0002-7676-3106; Lehti, Sami/0000-0003-1370-5598; Kara, Ozgun/0000-0002-4661-0096; Voutilainen, Mikko/0000-0002-5200-6477; Akgun, Bora/0000-0001-8888-3562; Myllymaki, Mikael/0000-0003-0510-3810; Luukka, Panja/0000-0003-2340-4641; Moran, Dermot/0000-0002-1941-9333; Zabolotny, Wojciech/0000-0002-6833-4846; Shevelev, Alexey/0000-0003-4600-0228; Martinez Rivero, Celso/0000-0002-3224-956X; Pozniak, Krzysztof/0000-0001-5426-1423; Hussain, Priya Sajid/0000-0002-4825-5278; Ligabue, Franco/0000-0002-1549-7107; Viinikainen, Jussi/0000-0003-2530-4265; Osherson, Marc/0000-0002-9760-9976; Lampen, Tapio/0000-0002-8398-4249; Chatterjee, Suman/0000-0003-2660-0349; Lassila-Perini, Kati/0000-0002-5502-1795; Kirschenmann, Henning/0000-0001-7369-2536; Ramos, Dayron/0000-0002-7165-1017; Navarrete Ramos, Efren/0000-0002-5180-4020; Shopova, Mariana/0000-0001-6664-2493; Heikkila, Jaana/0000-0002-0538-1469; Brucken, Jens Erik/0000-0001-6066-8756; Calderon, Dr. Alicia/0000-0002-7205-2040; Tapper, Alexander/0000-0003-4543-864X; Tuominen, Eija/0000-0002-7073-7767A 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.eninfo:eu-repo/semantics/openAccessArticle10.1103/PhysRevLett.133.1423012-s2.0-85206872004