Explanation of systematics of CMS<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="bold">p</mml:mi><mml:mo mathvariant="bold">+</mml:mo><mml:mi>Pb</mml:mi></mml:math>high multiplicity dihadron data at<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mi>NN</mml:mi></mml:msub><mml:mo mathvariant="bold">=</mml:mo><mml:mn>5.02</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math>

In a recent article [K. Dusling and R. Venugopalan, arXiv:1210.3890 [Phys. Rev. D (to be published)]], we showed that high multiplicity dihadron proton-proton ($\mathrm{p}+\mathrm{p}$) data from the CMS experiment are in excellent agreement with computations in the color glass condensate effective field theory. This agreement of the theory with several hundred data points provides a nontrivial description of both nearside (``ridge'') and awayside azimuthal collimations of long range rapidity correlations in $\mathrm{p}+\mathrm{p}$ collisions. Our prediction in Dusling and Venugopalan [arXiv:1210.3890 [Phys. Rev. D (to be published)]] for proton-lead ($\mathrm{p}+\mathrm{Pb}$) collisions is consistent with results from the recent CMS $\mathrm{p}+\mathrm{Pb}$ run at ${\sqrt{s}}_{\mathrm{NN}}=5.02\text{ }\text{ }\mathrm{TeV}$ for the largest track multiplicity ${N}_{\mathrm{track}}\ensuremath{\sim}40$ we considered. The CMS $\mathrm{p}+\mathrm{Pb}$ data shows the following striking features: (i) a strong dependence of the ridge yield on ${N}_{\mathrm{track}}$, with a significantly larger signal than in $\mathrm{p}+\mathrm{p}$ for the same ${N}_{\mathrm{track}}$, (ii) a stronger ${p}_{T}$ dependence than in $\mathrm{p}+\mathrm{p}$ for large ${N}_{\mathrm{track}}$, and (iii) a nearside collimation for large ${N}_{\mathrm{track}}$ comparable to the awayside for the lower ${p}_{T}={p}_{T}^{\mathrm{trig}}={p}_{T}^{\mathrm{assoc}}$ dihadron windows. We show here that these systematic features of the CMS $\mathrm{p}+\mathrm{Pb}$ di-hadron data are all described by the color glass condensate (with parameters fixed by the $\mathrm{p}+\mathrm{p}$ data) when we extend our prediction in Dusling and Venugopalan [arXiv:1210.3890 [Phys. Rev. D (to be published)]] to rarer high multiplicity events. We also predict the azimuthally collimated yield for yet unpublished windows in the ${p}_{T}^{\mathrm{trig}}$ and ${p}_{T}^{\mathrm{assoc}}$ matrix.

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