Szczegóły publikacji
Opis bibliograficzny
Dielectron production in central Pb-Pb collisions at $\sqrt{s}_{NN}$=5.02 TeV / S. Acharya, [et al.], B. BALIŚ, [et al.], M. GORGOŃ, [et al.], A. HORZYK, [et al.], M. JABŁOŃSKI, [et al.], J. P. KITOWSKI, [et al.], S. D. KORYCIAK, [et al.], T. M. LELEK, [et al.], E. M. MAJERZ, [et al.], R. W. MARCJAN, [et al.], P. G. RUSSEK, [et al.] // Physical Review . C ; ISSN 2469-9985. — Tytuł poprz.: Physical Review. C, Nuclear Physics ; ISSN: 0556-2813. — 2025 — vol. 112 iss. 5 art no. 054906, s. 054906-1-054906-27. — Bibliogr. s. 054906-19-054906-22, Abstr. — Publikacja dostępna online od: 2025-11-18
Autorzy (1063)
Dane bibliometryczne
| ID BaDAP | 164940 |
|---|---|
| Data dodania do BaDAP | 2025-12-18 |
| Tekst źródłowy | URL |
| DOI | 10.1103/xl6m-vbqk |
| Rok publikacji | 2025 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Creative Commons | |
| Czasopismo/seria | Physical Review, C |
Abstract
The first measurement of the 𝑒+𝑒− pair production at midrapidity and low invariant mass in central Pb-Pb collisions at √𝑠𝑁𝑁=5.02TeV at the Large Hadron Collider is presented. The yield of 𝑒+𝑒− pairs is compared with a cocktail of expected hadronic decay contributions in the invariant mass (𝑚𝑒𝑒 ) and pair transverse momentum (𝑝T,𝑒𝑒 ) ranges 𝑚𝑒𝑒<3.5GeV/𝑐2 and 𝑝T,𝑒𝑒<8GeV/𝑐 . For 0.18<𝑚𝑒𝑒<0.5GeV/𝑐2 the ratio of data to the cocktail of hadronic contributions amounts to 1.40±0.11(stat.)±0.23(syst.)±0.16(cocktail) and 1.42±0.11(stat.)±0.23(syst.)+0.24 −0.29(cocktail) , including or not including medium effects in the estimation of the heavy-flavor background, respectively. It is consistent with predictions from two different models for an additional contribution of thermal 𝑒+𝑒− pairs from the hadronic and partonic phases. In the intermediate-mass range (1.2<𝑚𝑒𝑒<2.6GeV/𝑐2 ), the pair transverse impact parameter of the 𝑒+𝑒− pairs (DCA𝑒𝑒 , where “DCA” denotes “distance of closest approach”) is used for the first time in Pb-Pb collisions to separate displaced dielectrons from heavy-flavor hadron decays from a possible (thermal) contribution produced at the interaction point. The data are consistent with a suppression of 𝑒+𝑒− pairs from 𝑐 ‾ 𝑐 and an additional prompt component. Finally, the first direct-photon measurement in the 10% most central Pb-Pb collisions at √𝑠𝑁𝑁=5.02TeV is reported via the study of virtual direct photons in the transverse momentum range 1<𝑝T<5GeV/𝑐 . A model including prompt photons, as well as photons from the preequilibrium and fluid-dynamic phases, can reproduce the result, while being at the upper edge of the data uncertainties.
