Počet záznamů: 1  

Charge correlations using the balance function in Pb-Pb collisions at root s(NN)=2.76 TeV

  1. 1.
    0395297 - UJF-V 2014 RIV NL eng J - Článek v odborném periodiku
    Abelev, B. - Adam, J. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Čepila, J. - Křelina, M. - Krus, M. - Kushpil, Vasilij - Kushpil, Svetlana - Mareš, Jiří A. - Pachr, M. - Petráň, M. - Petráček, V. - Polák, Karel - Pospíšil, V. - Šmakal, R. - Šumbera, Michal - Tlustý, D. - Vajzer, Michal - Wagner, V. - Zach, Č. - Závada, Petr
    Charge correlations using the balance function in Pb-Pb collisions at root s(NN)=2.76 TeV.
    Physics Letters. B. Roč. 723, 4-5 (2013), s. 267-279. ISSN 0370-2693
    Grant CEP: GA MŠk(CZ) LG13031
    Institucionální podpora: RVO:68378271 ; RVO:61389005
    Klíčová slova: ALICE LHC * balance function * charge correlations
    Kód oboru RIV: BG - Jaderná, atomová a mol. fyzika, urychlovače; BF - Elementární částice a fyzika vys. energií (FZU-D)
    Impakt faktor: 6.019, rok: 2013

    In high-energy heavy-ion collisions, the correlations between the emitted particles can be used as a probe to gain insight into the charge creation mechanisms. In this Letter, we report the first results of such studies using the electric charge balance function in the relative pseudorapidity (Delta eta) and azimuthal angle (Delta phi) in Pb-Pb collisions at root s(NN) = 2.76 TeV with the ALICE detector at the Large Hadron Collider. The width of the balance function decreases with growing centrality (i.e. for more central collisions) in both projections. This centrality dependence is not reproduced by HIJING, while AMPT, a model which incorporates strings and parton rescattering, exhibits qualitative agreement with the measured correlations in Delta phi but fails to describe the correlations in Delta eta. A thermal blast-wave model incorporating local charge conservation and tuned to describe the p(T) spectra and v(2) measurements reported by ALICE, is used to fit the centrality dependence of the width of the balance function and to extract the average separation of balancing charges at freeze-out. The comparison of our results with measurements at lower energies reveals an ordering with root s(NN): the balance functions become narrower with increasing energy for all centralities. This is consistent with the effect of larger radial flow at the LHC energies but also with the late stage creation scenario of balancing charges. However, the relative decrease of the balance function widths in Delta eta and Delta phi, with centrality from the highest SPS to the LHC energy exhibits only small differences. This observation cannot be interpreted solely within the framework where the majority of the charge is produced at a later stage in the evolution of the heavy-ion collision.
    Trvalý link: http://hdl.handle.net/11104/0225422