From In-In to Pb-Pb collisions: Lessons from high-precision Dilepton   Measurements
  The NA60 experiment has studied low mass muon pair production in In-In collisions at 158 AGeV with unprecedented precision. With these measurements one can constrain the in-medium modifications of hadrons embedded in nuclear matter more thoroughly than from previous experiments. In the present paper we argue that these constraints could be significantly further tightened and theoretical uncertainties in modeling of the medium evolution reduced by an additional experiment measuring low mass di-muon production in Pb-Pb collisions at 158 AGeV with the same resolution as provided by NA60 for the In-In system. 
Thorsten Renk, Joerg Ruppert