LoboVault Home

Evolution of pi^ 0 suppression in Au+ Au collisions from sqrt (s_NN)= 39 to 200 GeV

LoboVault

Please use this identifier to cite or link to this item: http://hdl.handle.net/1928/20523

Evolution of pi^ 0 suppression in Au+ Au collisions from sqrt (s_NN)= 39 to 200 GeV

Show full item record

Title: Evolution of pi^ 0 suppression in Au+ Au collisions from sqrt (s_NN)= 39 to 200 GeV
Author: Fields, Douglas E.; PHENIX Collaboration; Aidala, C.; Brooks, M.L.; Guo, L.; Jiang, X.; Kapustinsky, J.; Kunde, G.J.; Lee, D.M.; Leitch, M.J.; Liu, M.X.; McGaughey, P.L.; Sondheim, W.E.; Van Hecke, H.W.; You, Z.; Bassalleck, B.; Butsyk, S.; Younus, I.; Al-Ta’ani, H.; Dharmawardane, K.V.; Kyle, G.S.; Papavassiliou, V.; Pate, S.F.; Tennant, E.; Wang, X.R.
Abstract: Neutral-pion, _0, spectra were measured at midrapidity (|y| < 0.35) in Au+Au collisions at psNN = 39 and 62.4GeV and compared to earlier measurements at 200GeV in the 1 < pT < 10GeV/c transverse-momentum (pT ) range. The high-pT tail is well described by a power law in all cases and the powers decrease significantly with decreasing center-of-mass energy. The change of powers is very similar to that observed in the corresponding p+p-collision spectra. The nuclear-modification factors (RAA) show significant suppression and a distinct energy dependence at moderate pT in central collisions. At high pT , RAA is similar for 62.4 and 200GeV at all centralities. Perturbative-quantum-chromodynamics calculations that describe RAA well at 200GeV, fail to describe the 39GeV data, raising the possibility that the relative importance of initial-state effects and soft processes increases at lower energies. A conclusion that the region where hard processes are dominant is reached only at higher pT , is also supported by the xT dependence of the xT -scaling power-law exponent.
Date: 2012-05-10
Description: Preprint
URI: http://hdl.handle.net/1928/20523


Files in this item

Files Size Format View
Fields et al Ev ... ollisions from sqrt (s_NN) 192.2Kb Unknown View/Open

This item appears in the following Collection(s)

Show full item record

UNM Libraries

Search LoboVault


Browse

My Account