ترغب بنشر مسار تعليمي؟ اضغط هنا

Charm production in Pb+Pb collisions at the Large Hadron Collider energy

70   0   0.0 ( 0 )
 نشر من قبل Taesoo Song
 تاريخ النشر 2015
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We study charm production in Pb+Pb collisions at $sqrt{s_{rm NN}}=$2.76 TeV in the Parton-Hadron-String-Dynamics transport approach and the charm dynamics in the partonic and hadronic medium. The charm quarks are produced through initial binary nucleon-nucleon collisions by using the PYTHIA event generator taking into account the (anti-)shadowing incorporated in the EPS09 package. The produced charm quarks interact with off-shell massive partons in the quark-gluon plasma and are hadronized into $D$ mesons through coalescence or fragmentation close to the critical energy density, and then interact with hadrons in the final hadronic stage with scattering cross sections calculated in an effective Lagrangian approach with heavy-quark spin symmetry. The PHSD results show a reasonable $R_{rm AA}$ and elliptic flow of $D$ mesons in comparison to the experimental data for Pb+Pb collisions at $sqrt{s_{NN}}$ = 2.76 TeV from the ALICE Collaboration. We also study the effect of temperature-dependent off-shell charm quarks in relativistic heavy-ion collisions. We find that the scattering cross sections are only moderately affected by off-shell charm degrees of freedom. However, the position of the peak of $R_{rm AA}$ for $D$ mesons depends on the strength of the scalar partonic forces which also have an impact on the $D$ meson elliptic flow. The comparison with experimental data on the $R_{rm AA}$ suggests that the repulsive force is weaker for off-shell charm quarks as compared to that for light quarks. Furthermore, the effects from radiative charm energy loss appear to be low compared to the collisional energy loss up to transverse momenta of $sim$ 15 GeV/c.



قيم البحث

اقرأ أيضاً

293 - V. Topor Pop 2013
Effects of strong longitudinal colour electric fields (SCF), shadowing, and quenching on the open prompt charm mesons (D$^0$, D$^+$, D$^{*+}$, D${_s}{^+}$) production in central Pb + Pb collisions at $sqrt{s_{rm NN}}$ = 2.76 TeV are investigated with in the framework of the {small HIJING/B=B v2.0} model. We compute the nuclear modification factor $R_{rm PbPb}^{rm D}$, and show that the above nuclear effects constitute important dynamical mechanisms in the description of experimental data. The strength of colour fields (as characterized by the string tension $kappa$), partonic energy loss and jet quenching process lead to a suppression factor consistent with recent published data. Predictions for future beauty mesons measurements have been included. Ratios of strange to non-strange prompt charm mesons in central Pb + Pb and minimum bias (MB) $ p + p$ collisions at 2.76 TeV are also discussed. Minimum bias $p + p$ collisions which constitute theoretical baseline in our calculations are studied at the centre of mass energies $sqrt{s}$ = 2.76 TeV and 7 TeV.
We briefly review the predictions of the thermal model for hadron production in comparison to latest data from RHIC and extrapolate the calculations to LHC energy. Our main emphasis is to confront the model predictions with the recently released data from ALICE at the LHC. This comparison reveals an apparent anomaly for protons and anti-protons which we discuss briefly. We also demonstrate that our statistical hadronization predictions for J/$psi$ production agree very well with the most recent LHC data, lending support to the picture in which there is complete charmonium melting in the quark-gluon plasma (QGP) followed by statistical generation of J/$psi$ mesons at the phase boundary.
114 - Sushanta Tripathy 2020
Recent results for high multiplicity pp and p-Pb collisions have revealed that they exhibit heavy-ion-like behaviors. To understand the origin(s) of these unexpected phenomena, event shape observables such as transverse spherocity ($S_{rm 0}^{p_{rm T } = 1}$) and the relative transverse activity classifier ($R_{rm{T}}$) can be exploited as a powerful tools to disentangle soft (non-perturbative) and hard (perturbative) particle production. Here, the production of light-flavor hadrons is shown for various $S_{rm 0}^{p_{rm T} = 1}$ classes in pp collisions at $sqrt{s}$ = 13 $textrm{TeV}$ measured with the ALICE detector at the LHC are presented. The evolution of average transverse momentum ($langle p_{rm T}rangle$) with charged-particle multiplicity, and identified particle ratios as a function of $p_{rm T}$ for different $S_{rm 0}^{p_{rm T} = 1}$ are also presented. In addition, the system size dependence of charged-particle production in pp, p-Pb, and Pb-Pb collisions at $sqrt{s_{rm NN}}$ = 5.02 TeV is presented. The evolution of $langle p_{rm T}rangle$ in different topological regions as a function of $R_{rm{T}}$ are presented. Finally, using the same approach, we present a search for jet quenching behavior in small collision systems.
We study cold and hot nuclear matter effects on charmonium production in p+Pb collisions at $sqrt{s_text{NN}}=5.02$ TeV in a transport approach. At the forward rapidity, the cold medium effect on all the $cbar c$ states and the hot medium effect on t he excited $cbar c$ states only can explain well the $J/psi$ and $psi$ yield and transverse momentum distribution measured by the ALICE collaboration, and we predict a significantly larger $psi$ $p_text{T}$ broadening in comparison with $J/psi$. However, we can not reproduce the $J/psi$ and $psi$ data at the backward rapidity with reasonable cold and hot medium effects.
Using the EPOS3 model with UrQMD to describe the hadronic phase, we study the production of short-lived hadronic resonances and the modification of their yields and $p_{T}$ spectra in p-Pb collisions at $sqrt{s_{NN}}$ = 5.02 TeV. High-multiplicity p- Pb collisions exhibit similar behavior to mid-peripheral Pb-Pb collisions at LHC energies, and we find indications of a short-lived hadronic phase in p-Pb collisions that can modify resonance yields and $p_{T}$ spectra through scattering processes. The evolution of resonance production is investigated as a function of the system size, which is related to the lifetime of the hadronic phase, in order to study the onset of collective effects in p-Pb collisions. We also study hadron production separately in the core and corona parts of these collisions, and explore how this division affects the total particle yields as the system size increases.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا