Scholarlink

In ultraperipheral collisions (UPCs) involving relativistic heavy ions, the production of heavy-flavor coherent vector mesons through photon-nuclear interactions is a key focus due to its direct sensitivity to the nuclear gluon density. However, because the collision involves two lead ions that can function as both a target and a projectile for photons, experimental observations are subject to a two-way ambiguity. This ambiguity limits our capacity to investigate the very small-x zone where nonlinear QCD effects are expected by making it difficult to distinguish between contributions from high and low-energy photon-nucleus interactions. By using a forward neutron tagging approach in UPC PbPb collisions at 5.02 TeV, this article resolves the two-way ambiguity and reveals the observation of coherent heavy quarkonium photoproduction.

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Probing a New Regime of Ultra-Dense Gluonic Matter Using High-Energy Photons with the CMS Experiment

  • 会议论文

  • 发表日期：

    2025年

查看全文
  • Pranjal Verma

摘要

In ultraperipheral collisions (UPCs) involving relativistic heavy ions, the production of heavy-flavor coherent vector mesons through photon-nuclear interactions is a key focus due to its direct sensitivity to the nuclear gluon density. However, because the collision involves two lead ions that can function as both a target and a projectile for photons, experimental observations are subject to a two-way ambiguity. This ambiguity limits our capacity to investigate the very small-x zone where nonlinear QCD effects are expected by making it difficult to distinguish between contributions from high and low-energy photon-nucleus interactions. By using a forward neutron tagging approach in UPC PbPb collisions at 5.02 TeV, this article resolves the two-way ambiguity and reveals the observation of coherent heavy quarkonium photoproduction.