Study of the angular correlation between heavy-flavour decay electrons and charged unidentified particles in pp and p-Pb collisions with ALICE

摘要

The aim of relativistic heavy-ion collisions is to investigate the properties of the Quark-Gluon Plasma (QGP) phase, that is achieved at high-enough temperatures and/or densities. In this context, light on heavy-ion collisions (e. g. p-Pb) are used to assess Cold Nuclear Matter effects (CNM), while elementary hadronic collisions (e. g. proton-proton) provide tests for QCD (Quantum Chromodynamics) based calculations and baseline for studies with heavy- ions. Heavy quarks, i. e. charm and beauty, are very convenient in the characterization of the QGP. They are produced via initial hard parton-parton scatterings at the early stages of the collision and, therefore, they are a self-generated probe for the system created in the reaction. In this work the angular correlation between electrons from heavy-flavour hadron decays and charged particles was studied in pp (2.76 and 7 TeV) and p-Pb (5.02 TeV) collisions at the CERN Large Hadron Collider, using the ALICE detector. The correlation strengths were evaluated as a function of multiplicity in p-Pb collisions. In pp collisions the relative beauty (and charm) contribution to the total heavy-flavour decay electron yield was estimated using the measured correlation distribution and Monte Carlo templates.