Low-p(T) e(+)e(-) Pair Production in Au plus Au Collisions at root s(NN)=200 GeV and U plus U Collisions at root s(NN)=193 GeV at STAR
Low-p(T) e(+)e(-) Pair Production in Au plus Au Collisions at root s(NN)=200 GeV and U plus U Collisions at root s(NN)=193 GeV at STAR
复制标题
Au + Au 根部碰撞 s(NN)=200 GeV 中的低 p(T) e( )e(-) 对生成以及 STAR 处 U 加 U 根部碰撞 s(NN)=193 GeV
DOI：
10.1103/physrevlett.121.132301
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发表时间：
2018
影响因子：
8.6
通讯作者：
Bellwi
中科院分区：
文献类型：
--
作者：
Adam J;Adamczyk L;Adams J R;Adkins J K;Agakishiev G;Aggarwal M M;Ahammed Z;Ajitan;N N;Alekseev I;Anderson D M;Aoyama R;Aparin A;Arkhipkin D;Aschenauer E C;Ashraf M U;Atetalla F;Attri A;Averichev G S;Bai X;Bairathi V;Barish K;Bassill A J;Behera A;Bellwi
我们首次测量了非中心碰撞中低横向动量()的质量区和碰撞中的对的产生。在这些碰撞的40%-80%的中心度中，观察到显著的增强因子，表示为数据与已知强子贡献的比率。超额产额的峰值明显在低处，宽度()在40-40之间。超额部分的绝对截面弱依赖于中心性，而包含介质中加宽光谱函数的理论模型计算的超额部分的绝对截面和夸克胶子等离子体或强子鸡尾酒辐射的贡献随着参与核子的增加而显著增加。初始入射核和靶核产生的光子-光子相互作用的模型计算描述了观测到的超额产额，但不能再现分布。
We report first measurements ofpair production in the mass regionat low transverse momentum () in noncentralcollisions atandcollisions at. 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 lowwith a width () between 40 and. The absolute cross section of the excess depends weakly on centrality, while those from a theoretical model calculation incorporating an in-medium broadenedspectral 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 thedistributions.