Decisive test of color coherence in proton-nucleus collisions at the LHC.
Proton-nucleus collisions (p+A) at LHC energies provide a rigorous test of color glass condensate (CGC), a model proposed to describe the high energy limit of quantum chromodynamics. In the CGC the average multiplicity of charged particles at midrapidity in p+A collisions depends logarithmically on the number of participants, N(part). In contrast, the wounded nucleon model of independent nucleon-nucleon scatterings, verified at RHIC energies, predicts that multiplicity in p+A depends linearly on N(part). We argue that the dependence of mean multiplicity on N(part) in p+A collisions at LHC energies can single out a model of particle production, thus offering a stringent test of the CGC and the wounded nucleon model. Based on this observation we propose a novel experimental test of color coherence in p+A collisions.
RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA.
Adam
A
Bzdak
Vladimir
V
Skokov