NA61/SHINE ion program

Abstract

The Super Proton Synchrotron (SPS) at CERN covers one of the most interesting regions of the phase diagram (T - μ_{B}) of strongly interacting matter. The study of central Pb+Pb collisions by NA49 indicate that the threshold for deconfinement is reached already at the low SPS energies. Theoretical considerations predict a critical point of strongly interacting matter at energies accessible at the SPS. The NA61/SHINE experiment, a successor of the NA49 project, will study hadron production in p+p, p+A, h+A, and A+A reactions at various energies. The broad physics program includes the investigation of the properties of strongly interacting matter, as well as precision measurements of hadron spectra for the T2K neutrino experiment and for the Pierre Auger Observatory and KASCADE cosmic-ray projects. The main physics goals of the NA61/SHINE ion program are to study the properties of the onset of deconfinement at low SPS energies and to find signatures of the critical point of strongly interacting matter. To achieve these goals a broad range in the (T - μ_{B}) phase diagram will be covered by performing an energy (10A-158A GeV/c) and system size (p+p, B+C, Ar+Ca, Xe+La) scan. The first data for this 2-D scan were taken in 2009, i.e. p+p interactions at 20, 30, 40, 80, 158 GeV/c beam energy. This contribution will summarize physics arguments for the NA61/SHINE ion program, show the detector performance and present the current status of the experiment and plans for the next years.