Skewness and kurtosis of mean transverse momentum fluctuations at the LHC energies

0585802 - ÚJF 2025 RIV NL eng J - Journal Article
Acharya, S. - Adamová, Dagmar - Aglieri Rinella, G. - Agnello, M. - Bielčík, J. - Bielčíková, Jana - Broz, M. - Contreras, J. G. - Filová, V. - Grecká, Ekaterina - Grund, D. - Haidlová, S. - Herman, T. - Isakov, Artem - Khuntia, A. - Kotliarov, Artem - Křížek, Filip - Kushpil, Svetlana - Šafařík, K. - Torres, S. R. - Závada, Petr … Total 1054 authors
Skewness and kurtosis of mean transverse momentum fluctuations at the LHC energies.
Physics Letters. B. Roč. 850, MAR (2024), č. článku 138541. ISSN 0370-2693. E-ISSN 1873-2445
Research Infrastructure: CERN-CZ III - 90240
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * heavy ion coliisions
OECD category: Nuclear physics; Particles and field physics (FZU-D)
Impact factor: 4.3, year: 2022
Method of publishing: Open access
https://doi.org/10.1016/j.physletb.2024.138541

The first measurements of skewness and kurtosis of mean transverse momentum ( p(T)) fluctuations are reported in Pb-Pb collisions at root s(NN) = 5.02 TeV, Xe-Xe collisions at root s(NN) = 5.44 TeV and pp collisions at root s = 5.02 TeV using the ALICE detector. The measurements are carried out as a function of system size < dN(ch)/d eta >(1/3)(vertical bar eta vertical bar<0.5), using charged particles with transverse momentum (p(T)) and pseudorapidity (eta), in the range 0.2 < p(T) < 3.0 GeV/c and vertical bar eta vertical bar < 0.8, respectively. In Pb-Pb and Xe-Xe collisions, positive skewness is observed in the fluctuations of p(T) for all centralities, which is significantly larger than what would be expected in the scenario of independent particle emission. This positive skewness is considered a crucial consequence of the hydrodynamic evolution of the hot and dense nuclear matter created in heavy-ion collisions. Furthermore, similar observations of positive skewness for minimum bias pp collisions are also reported here. Kurtosis of p(T) fluctuations is found to be in good agreement with the kurtosis of Gaussian distribution, for most central Pb-Pb collisions. Hydrodynamic model calculations with MUSIC using Monte Carlo Glauber initial conditions are able to explain the measurements of both skewness and kurtosis qualitatively from semicentral to central collisions in Pb-Pb system. Color reconnection mechanism in PYTHIA8 model seems to play a pivotal role in capturing the qualitative behavior of the same measurements in pp collisions.
Permanent Link: https://hdl.handle.net/11104/0353475