Effects of momentum conservation and flow on angular correlations observed in experiments at the BNL Relativistic Heavy Ion Collider

摘要

When modeling heavy-ion collisions, one usually ignoresnmomentum conservation. Given the thousands of hadronsnemitted in central collisions at RHIC (the Relativistic HeavynIon Collider), such effects are of the order of a fraction ofna percent. However, as will be illustrated here, high-qualityndata sets measured by the STAR collaboration have sufficientnstatistics and coverage to identify and analyze correlations atnlevels better than 10−4, enabling the identification and analysisnof correlations due to momentum conservation.nIn the past year STAR has reported two-particle angularncorrelations of the form [1,2]