Speaker
Tsubasa Okubo
(Hiroshima University (JP))
Description
Strong suppression of high $p_{\rm T}$ particles has been observed in heavy-ion collisions at LHC energies,
which can be interpreted by various processes involving transport properties of the QCD medium and the initial
state effect. Proton-nucleus ($p$-$A$) collisions are intermediate between proton-proton ($pp$) and nucleus-nucleus
($A$-$A$) collisions in terms of system size and number of produced particles. Comparing particle production in $pp$,
$p$-$A$, $A$-$A$ reactions has frequently been used to separate initial state effects of colliding nuclei from final
state effects in quark matter created by the collisions. We have measured neutral pions emitted in $p$-Pb collisions
at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV with PHOS at the ALICE experiment.
The PHOS is a unique and precise photon spectrometer composed of lead-tungstate crystals. With its outstanding
performances of fine granularity and high energy resolution, neutral pions can be identified via two photon decays
at an excellent mass resolution $\sigma_{\rm m}$/m = 3 %. Raw yields of pions out of a 90 million minimum-bias event
sample were counted in invariant mass spectra. We will present the current status and results of the analysis.
| On behalf of collaboration: | ALICE |
|---|
Author
Tsubasa Okubo
(Hiroshima University (JP))
