Testing nuclear parton distributions with pA collisions at the TeV scale

作者:Quiroga Arias Paloma*; Milhano Jose Guilherme; Wiedemann Urs Achim
来源:Physical Review C, 2010, 82(3): 034903.
DOI:10.1103/PhysRevC.82.034903

摘要

Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution PDF) in the proton. The extension of these analyses to nuclear parton distribution functions (nPDFs) has attracted much interest in recent years. nPDFs are needed as benchmarks for the characterization of hot QCD matter in nucleus-nucleus collisions, and attract further interest since they may show novel signatures of nonlinear density-dependent QCD evolution. However, it is not known from first principles whether the factorization of long-range phenomena into process-independent parton distribution, which underlies global PDF extractions for the proton, extends to nuclear effects. As a consequence, assessing the reliability of nPDFs for benchmark calculations goes beyond testing the numerical accuracy of their extraction and requires phenomenological tests of the factorization assumption. Here, we argue that a proton-nucleus collision program at the Large Hadron Collider would provide a set of measurements, which allow for unprecedented tests of the factorization assumption, underlying global nPDF fits.

  • 出版日期2010-9-9