Dielectron production in proton-proton and proton-lead collisions at root s(NN)=5.02 TeV

0538354 - ÚJF 2021 RIV US eng J - Journal Article
Acharya, S. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Contreras, J. G. - Herman, T. - Horák, D. - Isakov, Artem - Křížek, Filip - Křížková Gajdošová, K. - Kushpil, Svetlana - Lavička, R. - Mareš, Jiří A. - Petráček, V. - Šafařík, K. - Šumbera, Michal - Závada, Petr … Total 1007 authors
Dielectron production in proton-proton and proton-lead collisions at root s(NN)=5.02 TeV.
Physical Review C. Roč. 102, č. 5 (2020), č. článku 055204. ISSN 2469-9985. E-ISSN 2469-9993
R&D Projects: GA MŠMT(CZ) LTT17018; GA MŠMT(CZ) LM2018104
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * heavy ion collisions
OECD category: Nuclear physics; Particles and field physics (FZU-D)
Impact factor: 3.296, year: 2020
Method of publishing: Open access
https://doi.org/10.1103/PhysRevC.102.055204

The first measurements of dielectron production at midrapidity (vertical bar eta(e)vertical bar < 0.8) in proton-proton and proton-lead collisions at root s(NN) = 5.02 TeV at the LHC are presented. The dielectron cross section is measured with the ALICE detector as a function of the invariant mass m(ee) and the pair transverse momentum p(T,ee) in the ranges m(ee) < 3.5 GeV/c(2) and p(T,ee) < 8 GeV/c, in both collision systems. In proton-proton collisions, the charm and beauty cross sections are determined at midrapidity from a fit to the data with two different event generators. This complements the existing dielectron measurements performed at root s = 7 and 13 TeV. The slope of the root s dependence of the three measurements is described by FONLL calculations. The dielectron cross section measured in proton-lead collisions is in agreement, within the current precision, with the expected dielectron production without any nuclear matter effects for e(+)e(-) pairs from open heavy-flavor hadron decays. For the first time at LHC energies, the dielectron production in proton-lead and proton-proton collisions are directly compared at the same root s(NN) via the dielectron nuclear modification factor R-pPb. The measurements are compared to model calculations including cold nuclear matter effects, or additional sources of dielectrons from thermal radiation.
Permanent Link: http://hdl.handle.net/11104/0316168