Systematic study of nuclear effects in <i>p</i> plus Al, <i>p</i> plus Au, <i>d</i> + Au, and <SUP>3</SUP>He + Au collisions at √<i>S<sub>NN</sub></i>=200 GeV using π<SUP>0</SUP> production
PHYSICAL REVIEW C, cilt.105, sa.6, 2022 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 105 Sayı: 6
- Basım Tarihi: 2022
- Doi Numarası: 10.1103/physrevc.105.064902
- Dergi Adı: PHYSICAL REVIEW C
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC
- Yıldız Teknik Üniversitesi Adresli: Hayır
Özet
The PHENIX Collaboration presents a systematic study of inclusive pi(0) production from p + p, p + Al, p + Au, d + Au, and He-3 + Au collisions at root S-NN = 200 GeV. Measurements were performed with different centrality selections as well as the total inelastic, 0-100%, selection for all collision systems. For 0-100% collisions, the nuclear-modification factors, R-xA, are consistent with unity for P-T above 8 GeV/c, but exhibit an enhancement in peripheral collisions and a suppression in central collisions. The enhancement and suppression characteristics are similar for all systems for the same centrality class. It is shown that for high-p(T)-pi(0) production, the nucleons in the d and He-3 interact mostly independently with the Au nucleus and that the counterintuitive centrality dependence is likely due to a physical correlation between multiplicity and the presence of a hard scattering process. These observations disfavor models where parton energy loss has a significant contribution to nuclear modifications in small systems. Nuclear modifications at lower p(T) resemble the Cronin effect-an increase followed by a peak in central or inelastic collisions and a plateau in peripheral collisions. The peak height has a characteristic ordering by system size as p + Au > d + Au > He-3 + Au > p + Al. For collisions with Au ions, current calculations based on initial-state cold nuclear matter effects result in the opposite order, suggesting the presence of other contributions to nuclear modifications, in particular at lower p(T).