Szczegóły publikacji
Opis bibliograficzny
Low-${p_T e^+e^−}$ pair production in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV and U+U collisions at $\sqrt{s_{NN}}$=193 GeV at STAR / J. Adam, L. ADAMCZYK, [et al.], Ł. FULEK, [et al.], M. PRZYBYCIEŃ, [et al.], R. SIKORA, [et al.] // Physical Review Letters ; ISSN 0031-9007. — 2018 — vol. 121 iss. 13 art. no. 132301, s. 132301-1–132301-8. — Bibliogr. s. 132301-7–132301-8
Autorzy (350)
Dane bibliometryczne
| ID BaDAP | 117746 |
|---|---|
| Data dodania do BaDAP | 2018-11-22 |
| Tekst źródłowy | URL |
| DOI | 10.1103/PhysRevLett.121.132301 |
| Rok publikacji | 2018 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Creative Commons | |
| Czasopismo/seria | Physical Review Letters |
Abstract
We report first measurements of e+e- pair production in the mass region 0.4<Mee<2.6 GeV/c2 at low transverse momentum (pT<0.15 GeV/c) in noncentral Au+Au collisions at sNN=200 GeV and U+U collisions at sNN=193 GeV. Significant enhancement factors, expressed as ratios of data over known hadronic contributions, are observed in the 40%-80% centrality of these collisions. The excess yields peak distinctly at low pT with a width (âpT2â ©) between 40 and 60 MeV/c. The absolute cross section of the excess depends weakly on centrality, while those from a theoretical model calculation incorporating an in-medium broadened ρ spectral function and radiation from a quark gluon plasma or hadronic cocktail contributions increase dramatically with an increasing number of participant nucleons. Model calculations of photon-photon interactions generated by the initial projectile and target nuclei describe the observed excess yields but fail to reproduce the pT2 distributions.
