Thu·Mar 26, 2015Thursday·March 26, 2015

1. 01*

   Rapidity and transverse-momentum dependence of the inclusive J/$\psi$ nuclear modification factor in p-Pb collisions at $\sqrt{{\text{s}}_{\mathbf{NN}}}=5.02$ TeV

   ALICE Collaboration

   We have studied the transverse-momentum ($p_{\mathrm{T}}$) dependence of the inclusive J/$\psi$ production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, in three center-of-mass rapidity ($y_{\mathrm{cms}}$) regions, down to zero $p_{\mathrm{T}}$. Results in the forward and backward rapidity ranges ($2.03<y_{\mathrm{cms}}<3.53$ and $-4.46<y_{\mathrm{cms}}<-2.96$) are obtained by studying the J/$\psi$ decay to ${\mu }^{+}{\mu }^{-}$, while the mid-rapidity region ($-1.37<y_{\mathrm{cms}}<0.43$) is investigated by measuring the ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ decay channel. The $p_{\mathrm{T}}$ dependence of the J/$\psi$ production cross section and nuclear modification factor are presented for each of the rapidity intervals, as well as the J/$\psi$ mean $p_{\mathrm{T}}$ values. Forward and mid-rapidity results show a suppression of the J/$\psi$ yield, with respect to pp collisions, which decreases with increasing $p_{\mathrm{T}}$. At backward rapidity no significant J/$\psi$ suppression is observed. Theoretical models including a combination of cold nuclear matter effects such as shadowing and partonic energy loss, are in fair agreement with the data, except at forward rapidity and low transverse momentum. The implications of the p-Pb results for the evaluation of cold nuclear matter effects on J/$\psi$ production in Pb-Pb collisions are also discussed.

   nucl-exhep-exJHEP(2015)·122 citations
2. 02*

   Sub-threshold $\varphi$ and ${\Xi }^{-}$ production by high mass resonances with UrQMD

   Jan Steinheimer🇩🇪 · Marcus Bleicher🇩🇪

   We present a possible explanation for the deep sub-threshold, $\varphi$ and ${\Xi }^{-}$ production yields measured with the HADES experiment in Ar+KCl reactions at $E_{\mathrm{lab}}=1.76$ A GeV and present predictions for Au+Au reactions at $E_{\mathrm{lab}}=1.23$ A GeV. To explain the surprisingly high yields of $\varphi$ and ${\Xi }^{-}$ hadrons we propose new decay channels for high mass baryon resonances. These new decay channels are constrained by elementary $\mathrm{p}+\mathrm{p}\to \mathrm{p}+\mathrm{p}+\varphi$ cross sections, and ${\Xi }^{-}$ production in p+Nb. Based on the fits to the elementary reactions one obtains a satisfactorily description of $\varphi$ and ${\Xi }^{-}$ production in deep sub-threshold Ar+KCl reactions as well as the observed nuclear transparency ratio in proton induced $\varphi$ production in cold nuclear matter. The results implicate that no new medium effects are required to describe the rare strange particle production data in low energy nuclear collisions.

   ↳ nucl-thnucl-exJ.Phys.G(2016)·74 citations
3. 03*

   Hydrodynamic modeling of pseudorapidity flow correlations in relativistic heavy-ion collisions and the torque effect

   Piotr Bozek🇵🇱 · Wojciech Broniowski🇵🇱 · Adam Olszewski🇵🇱

   We analyze correlations between the event-plane angles in different intervals of pseudorapidity within the 3+1-dimensional viscous hydrodynamics with the Glauber-model initial conditions. As predicted earlier, the fluctuations in the particle production mechanism in the earliest stage, together with asymmetry of the emission profiles in pseudorapidity from the forward- and backward going wounded nucleons, lead to the torque effect, namely, decorrelation of the event-plane angles in distant pseudorapidity bins. We use two- or three-bin measures of correlation functions to quantify the effect, with the latter compared to the recent data from the CMS collaboration. We find a sizable torque effect, with magnitude larger at RHIC than at the LHC.

   ↳ nucl-thhep-phnucl-exPRC(2015)·31 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.