"Table 13" of "Evidence for collectivity in pp collisions at the LHC"

CERN-LHC. Measurements of two- and multi-particle angular correlations in pp collisions at sqrt(s) = 5, 7, and 13 TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0 inverse picobarn (5 TeV), 6.2 inverse picobarns (7 TeV), and 0.7 inverse picobarns (13 TeV), were collected using the CMS detector at the LHC. The second-order (v[2]) and third-order (v[3]) azimuthal anisotropy harmonics of unidentified charged particles, as well as v[2] of K0 short and Lambda/anti-Lambda particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v[2] values of charged hadrons (mostly pions), K0 short, and Lambda/anti-Lambda, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pt of about 2 GeV/c. For 13 TeV data, the v[2] signals are also extracted from four- and six-particle correlations for the first time in pp collisions, with comparable magnitude to those from two-particle correlations. These observations are similar to those seen in pPb and PbPb collisions, and support the interpretation of a collective origin for the observed long-range correlations in high-multiplicity pp collisions.

本数据集呈现了质心系能量√s=5、7和13 TeV的质子-质子（pp）碰撞中，两粒子及多粒子角关联随带电粒子多重数的测量结果。所用实验数据的积分亮度分别为1.0 逆皮可靶恩（pb⁻¹，5 TeV）、6.2 逆皮可靶恩（pb⁻¹，7 TeV）及0.7 逆皮可靶恩（pb⁻¹，13 TeV），由大型强子对撞机（LHC）上的紧凑缪子线圈（CMS，Compact Muon Solenoid）探测器采集获取。研究从长程两粒子关联中提取了未鉴别带电粒子的二阶（v₂）与三阶（v₃）方位各向异性谐波，以及K⁰_S介子（K-short）、Λ超子与反Λ超子（Λ/anti-Λ）的二阶方位各向异性谐波v₂，提取结果以粒子多重数和横向动量（Transverse Momentum, p_T）为自变量。在高多重数pp碰撞事件中，带电强子（主要为π介子）、K⁰_S介子与Λ/anti-Λ超子的v₂值呈现质量依赖的排序规律：在横向动量p_T约2 GeV/c以下时，粒子质量越轻，其方位各向异性信号越强。针对13 TeV的数据，本研究首次在pp碰撞中通过四粒子与六粒子关联提取得到v₂信号，其强度与两粒子关联得到的信号相当。上述观测结果与pPb及PbPb碰撞中的已有观测结果一致，支持高多重数pp碰撞中观测到的长程关联起源于集体效应的理论解释。