论文标题
横向质量缩放棚可以阐明LHC $υ$介子生产的事件活动依赖性吗？
Can Transverse Mass Scaling Shed Light on the Event-Activity Dependence of $Υ$ Mesons Production at LHC?
论文作者
论文摘要
CMS实验的测量[CMS Collaboration，JHEP04（2014）103; CMS协作，JHEP11（2020）001]在具有较高$υ$（NS）州的事件中揭示了带电粒子轨道的不足。该观察结果被认为是$ pp $互动中激发的底部抑制作用的体现。横向质量（$ M _ {\ Mathrm {t}} $）可以暗示以独立的方式检查此假设。从SPS到RHIC和LHC的各种能量的质子蛋白碰撞中，已经观察到了广泛的粒子物种的缩放率。已知观察到的缩放率在重子和介子中是不同的，这项工作对$ m _ {\ mathrm {t}} $ - 在LHC Energies的梅森牛肉缩放的全面研究，重点是较重的ersons。该研究证明了与粒子夸克含量相关的介体性能中的模式。特别是，轻质物种和地下夸克尼亚遵守相同的缩放，而开放味的颗粒则偏离了它，因为它们的光谱更加困难。偏差的大小取决于介子中最重的夸克的风味。通过将$ m _ {\ mathrm {t}} $ - 缩放假设扩展到激发的底部态状态，可以观察到，与缩放量表的预期相比，测量的$υ$（2s）和$υ$（2s）和$υ$（3s）的跨部分减少了1.6和2.4。该观察结果与最近观察到的不同$υ$（NS）梅森状态的事件活性依赖性之间的差异是一致的。
Measurements by the CMS experiment [CMS Collaboration, JHEP04 (2014) 103; CMS Collaboration, JHEP11 (2020) 001] reveal a deficit of charged particle tracks in events with higher $Υ$(nS) states. This observation is suggested to be a manifestation of the excited bottomonia suppression in $pp$ interactions. Transverse mass ($m_{\mathrm{T}}$) scaling can be implied to check this assumption in an independent way. The scaling has been observed for a wide range of particle species in proton-proton collisions at various energies from the SPS to RHIC and the LHC. The observed scaling is known to be different for baryons and mesons, and this work presents a comprehensive study of the $m_{\mathrm{T}}$-scaling of mesons at LHC energies with a focus on heavier mesons. The study demonstrates patterns in the scaling properties of mesons, which are related to the particle quark content. In particular, light species and ground-state quarkonia obey the same scaling, whereas open-flavor particles deviate from it because their spectra are significantly harder. The magnitude of deviation depends on the flavor of the heaviest quark in the meson. By extending the $m_{\mathrm{T}}$-scaling assumption to the excited bottomonia states, it is observed that the measured cross sections of $Υ$(2S) and $Υ$(3S) are reduced by factors of 1.6 and 2.4 compared to the expectation from the scaling. This observation is consistent with recently observed differences between the event-activity dependence of different $Υ$(nS) meson states.
