New results and perspectives on R_{AA} measurements below 20 GeV CM-energy at fixed target machines

Abstract

Transverse momentum spectra of pi^{+/-} at midrapidity are measured at high p_T in p+p and p+Pb collisions at 158 GeV/nucleon beam energy by the NA49 experiment. This study is complementary to our previous results on the same spectra from Pb+Pb collisions. The nuclear modification factors R_{A+A/p+p}, R_{p+A/p+p} and R_{A+A/p+A} as a function of p_T are extracted and compared to RHIC measurements, thus providing insight into the energy dependence of nuclear modification. The modification factor R_{A+A/p+A} proved to be consistent with our previous results on the central to peripheral modification factor R_{CP}. The limitation of our current p_T range is discussed and planned future upgrades are outlined. Some aspects of the FAIR-CBM experiment are also presented as a natural future continuation of the measurements at very high p_T.