PROSPECTS OF MEDIUM TOMOGRAPHY USING 2-, 3- AND 4-PARTICLE CORRELATIONS FOR A (SEMI)-HARD TRIGGER

Hard partons propagating through hot and dense matter lose energy, leading to the observed depletion of hard hadron spectra in nucleus nucleus collision as compared to scaled proton proton collisions. This lost energy has to be redistributed in the medium due to the conservation of energy, which is manifest in the pT dependence of the angular correlation pattern of hadrons associate with a (semi-) hard trigger. While at low pT a splitting of a broad peak is observed, at high pT the structure shows vacuum width, albeit with reduced yield. This sugests a transfer of energy from hard partons to a collectively recoiling medium. We present a systematic study of these phenomena using a realistic medium evolution and a Monte-Carlo simulation of the experimental trigger and show what information about the medium can be derived from multiparticle correlations.