标题： 光子碎裂函数的新信息 显示英文标题

标题： New information on photon fragmentation functions

摘要： 在重离子碰撞中辐射的热光子代表了一种新物质状态——禁闭夸克-胶子等离子体的重要的信号。然而，要清晰地识别这一信号，需要精确了解由夸克和胶子在硬碰撞中产生的即时光子，主要是通过它们的碎裂过程。 在这篇文章中，我们证明了由PHENIX实验组提供的在质子-质子碰撞中产生的低横动量光子数据能够提取关于这一碎裂过程的新信息。尽管现有的数据还没有明确地倾向于一种参数化（BFG II）而非另外两种常用的光子碎裂函数（BFG I 和 GRV NLO），但PHENIX和STAR实验组在BNL RHIC于2013年记录的数据集，其统计精度提高了十倍，应该能够进行这样的分析。 显示英文摘要

摘要： Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of the prompt photons produced simultaneously in hard collisions of quarks and gluons, mostly through their fragmentation. In this paper, we demonstrate that PHENIX data on photons produced in proton-proton collisions with low transverse momenta allow to extract new information on this fragmentation process. While existing data do not yet convincingly favor one parameterization (BFG II) over the two other frequently used photon fragmentation functions (BFG I and GRV NLO), the data sets recorded by PHENIX and STAR at BNL RHIC in 2013 with tenfold higher statistics should allow for such an analysis.