This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of $1.4<|\mathrm{\Delta }\eta |<1.8$ and a transverse momentum of $1<p_{\mathrm{T}}<2\mathrm{GeV}/c$, as a function of the charged-particle multiplicity measured at midrapidity. This Letter extends the measurements of the ridge yield to the low multiplicity region, where in hadronic collisions it is typically conjectured that a strongly interacting medium is unlikely to be formed. The precision of the new low multiplicity results allows for the first direct quantitative comparison with the results obtained in ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ collisions at $\sqrt{s}=91\mathrm{GeV}$ and $\sqrt{s}=183–209\mathrm{GeV}$, where initial-state effects such as preequilibrium dynamics and collision geometry are not expected to play a role. In the multiplicity range $8\lesssim ⟨N_{\mathrm{ch}}⟩\lesssim 24$ where the ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ results have good precision, the measured ridge yields in $pp$ collisions are substantially larger than the limits set in ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ annihilations. Consequently, the findings presented in this Letter suggest that the processes involved in ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ annihilations do not contribute significantly to the emergence of long-range correlations in $pp$ collisions.

中文翻译：

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低多重质子-质子碰撞中长程角相关性的出现

这封信介绍了近侧相关每次触发产量（表示为脊产量）的测量，来自对质子-质子碰撞中带电强子的角度相关性的分析$\sqrt{s}=13\mathrm{TeV}$。长距离脊产率是针对伪快差为带电粒子对提取的$1.4<|\mathrm{\Delta }\eta |<1.8$和横向动量$1<p_{\mathrm{时间}}<2\mathrm{GeV}/C$，作为中速测量的带电粒子多重性的函数。这封信将脊产量的测量扩展到低重数区域，在强子碰撞中，通常推测不太可能形成强相互作用介质。新的低多重性结果的精度允许与中获得的结果进行首次直接定量比较${\mathrm{e}}^{+}{\mathrm{e}}^{-}$碰撞于$\sqrt{s}=91\mathrm{GeV}$和$\sqrt{s}=183–209\mathrm{GeV}$，其中预平衡动力学和碰撞几何等初始状态效应预计不会发挥作用。在多重性范围内$8\lesssim ⟨{氮}_{\mathrm{ch}}⟩\lesssim 24$哪里的${\mathrm{e}}^{+}{\mathrm{e}}^{-}$结果精度良好，测量的脊产量$pp$碰撞远远大于中设定的限制${\mathrm{e}}^{+}{\mathrm{e}}^{-}$湮灭。因此，这封信中提出的调查结果表明，涉及的过程${\mathrm{e}}^{+}{\mathrm{e}}^{-}$湮灭对长期相关性的出现没有显着贡献$pp$碰撞。