Anomalous Evolution of the Near-Side Jet Peak Shape in Pb-Pb Collisions at root S-NN=2.76 TeV

0479646 - ÚJF 2018 RIV US eng J - Článek v odborném periodiku
Adam, J. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Čepila, J. - Contreras, J. G. - Eyyubova, G. - Ferencei, Jozef - Hladký, Jan - Horák, D. - Křížek, Filip - Kučera, Vít - Kushpil, Svetlana - Mareš, Jiří A. - Petráček, V. - Pospíšil, Jan - Šumbera, Michal - Vaňát, Tomáš - Závada, Petr … celkem 1005 autorů
Anomalous Evolution of the Near-Side Jet Peak Shape in Pb-Pb Collisions at root S-NN=2.76 TeV.
Physical Review Letters. Roč. 119, č. 10 (2017), č. článku 102301. ISSN 0031-9007. E-ISSN 1079-7114
Grant CEP: GA MŠMT(CZ) LG15052
Institucionální podpora: RVO:68378271 ; RVO:61389005
Klíčová slova: ALICE collaboration * heavy ion collisions * LHC
Obor OECD: Nuclear physics; Particles and field physics (FZU-D)
Impakt faktor: 8.839, rok: 2017

The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a p(T) region inaccessible by direct jet identification. In these measurements pseudorapidity (Delta(eta)) and azimuthal (Delta phi) differences are used to extract the shape of the near-side peak formed by particles associated with a higher p(T) trigger particle (1 < p(T,trig) < 8 GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at root s(NN) = 2.76 TeV. A significant broadening of the peak in the Delta(eta) direction at low p(T) is found from peripheral to central collisions, which vanishes above 4 GeV/c, while in the Delta(phi) direction the peak is almost independent of centrality. For the 10% most central collisions and 1 < p(T,assoc) < 2 GeV/c, 1 < p(T,trig) < 3 GeV/c a novel feature is observed: a depletion develops around the center of the peak. The results are compared to pp collisions at the same center of mass energy and AMPT model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.
Trvalý link: http://hdl.handle.net/11104/0275618