Comparison of the color glass condensate to dihadron correlations in proton-proton and proton-nucleus collisions

Abstract

We perform a detailed comparison of long-range rapidity correlations in the color glass condensate framework to high multiplicity dihadron data in proton-proton and proton-lead collisions from the CMS, ALICE and ATLAS experiments at the LHC. The overall good agreement thus far of the nontrivial systematics of theory with data is strongly suggestive of gluon saturation and the presence of subtle quantum interference effects between rapidity separated gluons. In particular, the yield of pairs collimated in their relative azimuthal angle $\ensuremath{\Delta}\ensuremath{\phi}\ensuremath{\sim}0$, is sensitive to the shape of unintegrated gluon distributions in the hadrons that are renormalization group evolved in rapidity from the beam rapidities to those of the measured hadrons. We present estimates for the collimated dihadron yield expected in central deuteron-gold collisions at the Relativistic Heavy Ion Collider.