Quark Matter 2014 - XXIV International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

Neutral Pions Measured in the ALICE Electromagnetic Calorimeter in pp and p-Pb Collisions at sNN = 5.02 TeV

20 May 2014, 16:30

2h

spectrum (darmstadtium)

Board: E-12

Poster Jets Poster session

Speaker

Jason Adrian Kamin (Johann-Wolfgang-Goethe Univ. (DE))

Description

Light neutral mesons are among the most plentiful particles produced at the LHC and therefore serve as an ideal testing ground for pQCD in both pp and A-A collisions. Additionally, they provide a critical foundation upon which other analyses (direct photon, dilepton, etc) base their background determination. The nuclear modification factor $R_{\mathrm{AA}}$ shows a dramatic suppression in heavy ion collisions with respect to the pp baseline expectation presumably due to the formation of quark-gluon plasma (QGP). However, in order to disentangle how much of this phenomenon is simply a result of effects from "cold" nuclear matter in the initial state, p-A collisions are a necessary and useful control measurement. The ALICE electromagnetic calorimeter (EMCal) encompasses a large geometric acceptance of 100 degrees in azimuth and $|\eta |<0.7$ in pseudorapidity leading to a high statistics dataset. ${\pi }^0$ production is measured via the diphoton decay channel in pp collisions at $\sqrt{s}=2.76$TeV and in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$TeV. The status of the analysis of the differential invariant cross section for neutral pions as well as $R_{\mathrm{p}\mathrm{P}\mathrm{b}}$ will be presented for various centralities measured in the EMCal.