Do you want to publish a course? Click here

Spectra and elliptic flow of charmed hadrons in HYDJET++ model

124   0   0.0 ( 0 )
 Added by Gyulnara Eyyubova
 Publication date 2015
  fields
and research's language is English
 Authors G. Eyyubova




Ask ChatGPT about the research

Heavy-flavour quarks are predominantly produced in hard scatterings on a short time-scale and traverse the medium interacting with its constituents, thus they are one of the effective probes of the transport properties of the medium formed in relativistic heavy ion collisions. On the other hand, the thermal production of heavy-flavour quarks in quark-gluon plasma (QGP) is itself of interest. In this report, the production and elliptic flow of the prompt charmed mesons $D^0$, $D^+$, $D^{*+}$ and $J/psi$ in PbPb collisions at the center-of-mass energy 2.76 TeV per nucleon pair are described in the framework of two-component HYDJET++ model. The model combines thermal and pQCD production mechanisms. The spectra and elliptic flow of charmed mesons are presented, the results are compared with LHC data.



rate research

Read More

383 - T.S.Biro , Z.Szendi 2013
Theory Summary Talk given by Tamas S. Biro at SQM 2013, Birmingham, UK.
We present a study of transverse momentum ($p_{T}$) spectra of unidentified charged particles in pp collisions at RHIC and LHC energies from $sqrt{s}$ = 62.4 GeV to 13 TeV using Tsallis/Hagedorn function. The power law of Tsallis/Hagedorn form gives excellent description of the hadron spectra in $p_{T}$ range from 0.2 to 300 GeV/$c$. The power index $n$ of the $p_T$ distributions is found to follow a function of the type $a+b/sqrt {s}$ with asymptotic value $a = 5.72$. The parameter $T$ governing the soft bulk contribution to the spectra remains almost same over wide range of collision energies. We also provide a Tsallis/Hagedorn fit to the $p_{T}$ spectra of hadrons in pPb and different centralities of PbPb collisions at $sqrt{s_{NN}}$ = 5.02 TeV. The data/fit shows deviations from the Tsallis distribution which become more pronounced as the system size increases. We suggest simple modifications in the Tsallis/Hagedorn power law function and show that the above deviations can be attributed to the transverse flow in low $p_T$ region and to the in-medium energy loss in high $p_T$ region.
Charmed dibaryon states with the spin-parity $J^{pi}=0^+$, $1^+$, and $2^+$are predicted for the two-body $Y_cN$ ($=Lambda_c$, $Sigma_c$, or $Sigma^*_c$) systems. We employ the complex scaling method for the coupled channel Hamiltonian with the $Y_cN$-CTNN potentials, which were proposed in our previous study. We find four sharp resonance states near the $Sigma_c N$ and $Sigma^*_c N$ thresholds. From the analysis of the binding energies of partial channel systems, we conclude that these resonance states are Feshbach resonances. We compare the results with the $Y_c N$ resonance states in the heavy quark limit, where the $Sigma_c N$ and $Sigma^*_c N$ thresholds are degenerate, and find that they form two pairs of the heavy-quark doublets in agreement with the heavy quark spin symmetry.
We introduce a framework called Heavy Quarkonium Quantum Dynamics (HQQD) which can be used to compute the dynamical suppression of heavy quarkonia propagating in the quark-gluon plasma using real-time in-medium quantum evolution. Using HQQD we compute large sets of real-time solutions to the Schr{o}dinger equation using a realistic in-medium complex-valued potential. We sample 2 million quarkonia wave packet trajectories and evolve them through the QGP using HQQD to obtain their survival probabilities. The computation is performed using three different HQQD model parameter sets in order to estimate our systematic uncertainty. After taking into account final state feed down we compare our results to existing experimental data for the suppression and elliptic flow of bottomonium states and find that HQQD predictions are good agreement with available data for $R_{AA}$ as a function of $N_{rm part}$ and $p_T$ collected at $sqrt{s_{rm NN}} =$ 5.02 TeV. In the case of $v_2$ for the various states, we find that the path-length dependence of $Upsilon(1s)$ suppression results in quite small $v_2$ for $Upsilon(1s)$. Our prediction for the integrated elliptic flow for $Upsilon(1s)$ in the $10{-}90$% centrality class, which now includes an estimate of the systematic error, is $v_2[Upsilon(1s)]$ = 0.003 $pm$ 0.0007 $pm,^{0.0006}_{0.0013}$. We also find that, due to their increased suppression, excited bottomonium states have a larger elliptic flow. Based on this observation we make predictions for $v_2[Upsilon(2s)]$ and $v_2[Upsilon(3s)]$ as a function of centrality and transverse momentum.
We compute the suppression and elliptic flow of bottomonium using real-time solutions to the Schr{o}dinger equation with a realistic in-medium complex-valued potential. To model the initial production, we assume that, in the limit of heavy quark masses, the wave-function can be described by a lattice-smeared (Gaussian) Dirac delta wave-function. The resulting final-state quantum-mechanical overlaps provide the survival probability of all bottomonium eigenstates. Our results are in good agreement with available data for $R_{AA}$ as a function of $N_{rm part}$ and $p_T$ collected at $sqrt{s_{rm NN}} =$ 5.02 TeV. In the case of $v_2$ for the various states, we find that the path-length dependence of $Upsilon(1s)$ suppression results in quite small $v_2$ for $Upsilon(1s)$. Our prediction for the integrated elliptic flow for $Upsilon(1s)$ in the $10{-}90$% centrality class is $v_2[Upsilon(1s)] = 0.0026 pm 0.0007$. We additionally find that, due to their increased suppression, excited bottomonium states have a larger elliptic flow and we make predictions for $v_2[Upsilon(2s)]$ and $v_2[Upsilon(3s)]$ as a function of centrality and transverse momentum. Similar to prior studies, we find that it is possible for bottomonium states to have negative $v_2$ at low transverse momentum.
comments
Fetching comments Fetching comments
Sign in to be able to follow your search criteria
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا