Measurements of the heavy-flavour nuclear modification factor in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV with ALICE at the LHC

Abstract

The heavy-flavour nuclear modification factor $R_{\rm pPb}$ has been measured with the ALICE detector in p--Pb collisions at the nucleon--nucleon center of mass energy $\sqrt{s_{\rm NN}}$ = 5.02 TeV at the CERN LHC in a wide rapidity and transverse momentum range, as well as in several decay channels. $R_{\rm pPb}$ is consistent with unity within uncertainties at mid-rapidity and forward rapidity. In the backward region a slight enhancement of the yield of heavy-flavour decay muons is found in the region $2<p_{\rm T}<4$ GeV/$c$. The results are described within uncertainties by theoretical calculations that include initial-state effects. The measurements add experimental evidence that the suppression of heavy-flavour production observed at high $p_{\rm T}$ in central Pb--Pb collisions with respect to pp collisions is due to a medium effect induced by the interaction of heavy quarks with the partonic matter.