Detection of D mesons via hadronic decays in Pb–Pb collisions at LHC with ALICE

The ALICE experiment is devoted to the study of heavy-ion collisions at the CERN LHC collider. We present the results of a feasibility study for the detection of D → Kπ decays in Pb–Pb collisions with ALICE. 1 Physics motivation The aim of the ALICE [1] experiment is to study the behaviour of nuclear matter in the conditions of high densities and temperatures in which a transition to a deconfined QCD phase (Quark Gluon Plasma) is expected. The study of open charm production is of primary interest for two main reasons: • the interaction of the produced charm quarks with the plasma may reduce their momenta because of elastic collisions and in-medium gluon emissions (see e.g. Ref. [2] and references therein); • secondary parton scattering in the high-density partonic system produced may provide an additional source of charm quarks [3]. The measurement of the total charm production cross section and of the transverse momentum distribution of charm quarks in Pb–Pb collisions, as well as in pp and in pA interactions, is essential to study these open issues. The exclusive reconstruction of D mesons in the hadronic decay channel (D → Kπ, branching ratio = 3.83%) will provide a direct measurement of charm kinematical distributions.