PDF(Pubmed)
Abstract：
Events with no charged particles produced between the two leading jets are studied in proton-proton collisions at s = 7 TeV . The jets were required to have transverse momentum p T jet > 40 GeV and pseudorapidity 1.5 < | η jet | < 4.7 , and to have values of η jet with opposite signs. The data used for this study were collected with the CMS detector during low-luminosity running at the LHC, and correspond to an integrated luminosity of 8 pb - 1 . Events with no charged particles with p T > 0.2 GeV in the interval - 1 < η < 1 between the jets are observed in excess of calculations that assume no color-singlet exchange. The fraction of events with such a rapidity gap, amounting to 0.5-1% of the selected dijet sample, is measured as a function of the p T of the second-leading jet and of the rapidity separation between the jets. The data are compared to previous measurements at the Tevatron, and to perturbative quantum chromodynamics calculations based on the Balitsky-Fadin-Kuraev-Lipatov evolution equations, including different models of the non-perturbative gap survival probability.
摘要：
在s=7TeV的质子-质子碰撞中研究了在两个前导射流之间没有产生带电粒子的事件。要求射流的横向动量pT射流>40GeV，伪快度1.5<|η射流|<4.7，并具有符号相反的η喷射值。本研究使用的数据是在LHC低光度运行期间使用CMS检测器收集的，并对应于8pb-1的积分光度。在射流之间的间隔-1<η<1中观察到没有带电粒子且pT>0.2GeV的事件超过了假定没有颜色-单线态交换的计算。具有如此快速差距的事件的一小部分，相当于选定dijet样品的0.5-1%，作为第二前导射流的pT和射流之间的速度间隔的函数来测量。将数据与Tevatron的先前测量结果进行比较，并基于Balitsky-Fadin-Kuraev-Lipatov进化方程进行微扰量子色动力学计算，包括非扰动间隙生存概率的不同模型。
