Thu·Sep 7, 2017Thursday·September 7, 2017

1. 01*

   Energy dependent forward B $\to$ $J/\psi$ measurements in p+p collisions at PHENIX

   Xuan Li (for the PHENIX Collaboration)🇺🇸

   The heavy flavor studies at RHIC help improve the knowledge of the bottom/charm quark production and can test Quantum Chromodynamics (QCD). Compared to the LHC/Tevatron, the RHIC heavy flavor production originates from different partonic sub-processes and has a complementary kinematic coverage. The PHENIX forward rapidity silicon vertex detector (FVTX) provides precise determination of the event vertex, tracking and the Distance of Closest Approach (DCA) of charged tracks. This detector allows direct access to the $B$ meson production via measurements of non-prompt $J/\psi \to {\mu }^{+}+{\mu }^{-}$ within $1.2<|y|<2.2$ rapidity in $p$+$p$ collisions at $\sqrt{s}=$ 510 and 200 GeV. Comparison among PHENIX measurements of the $B\to J/\psi$ fraction with integrated $J/\psi$ $p_T$ up to 5 GeV$/c$ and higher energy results at the Tevatron and the LHC presents a smooth center of mass energy dependence from 0.2 to 13 TeV in $p$+$p$ ($p$+$\bar{p}$) collisions. The Next-To-Leading order Perturbative QCD (NLO pQCD) calculations are in reasonable agreement with the extracted total $b\bar{b}$ cross section based on the $B\to J/\psi$ fraction measurements at PHENIX.

   nucl-exhep-exhep-phPoS(2018)·0 citations
2. 02*

   Kaon femtoscopy in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV

   ALICE Collaboration

   We present the results of three-dimensional femtoscopic analyses for charged and neutral kaons recorded by ALICE in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV. Femtoscopy is used to measure the space-time characteristics of particle production from the effects of quantum statistics and final-state interactions in two-particle correlations. Kaon femtoscopy is an important supplement to that of pions because it allows one to distinguish between different model scenarios working equally well for pions. In particular, we compare the measured 3D kaon radii with a purely hydrodynamical calculation and a model where the hydrodynamic phase is followed by a hadronic rescattering stage. The former predicts an approximate transverse mass ($m_{\mathrm{T}}$) scaling of source radii obtained from pion and kaon correlations. This $m_{\mathrm{T}}$ scaling appears to be broken in our data, which indicates the importance of the hadronic rescattering phase at LHC energies. A $k_{\mathrm{T}}$ scaling of pion and kaon source radii is observed instead. The time of maximal emission of the system is estimated using the three-dimensional femtoscopic analysis for kaons. The measured emission time is larger than that of pions. Our observation is well supported by the hydrokinetic model predictions.

   nucl-exhep-exPRC(2017)·70 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.