arXiv subjects

Fenglan Shao

Publications and source records attributed to Fenglan Shao.

3 recordsLinked to original sources

arXiv2022

Collision centrality and energy dependence of strange hadron production in Au + Au collisions at \sqrt{s_{NN}}= 7.7-54.4 GeV

We apply an equal-velocity quark combination model to systematically study the transverse momentum (p_{T}) spectra of strange hadrons K_{S}^{0}, \phi, \Lambda, \Xi^{-}, \Omega^{-}, \bar{\Lambda}, \bar{\Xi}^{+} and \bar{\Omega}^{+} at mid-rapidity in Au+Au collisions at \sqrt{s_{NN}}= 7.7, 11.5, 19.6, 27, 39, 54.4 GeV. Relative deviation between the model calculation and experimental data of these eight hadrons is generally about 2-3% at \sqrt{s_{NN}}= 27, 39, 54.4 GeV and in central collisions at 7.7, 11.5, 19.6 GeV. The deviation slightly increases up to about 4% in the semi-central and peripheral collision at \sqrt{s_{NN}}= 7.7, 11.5, 19.6 GeV. We systematically explain the dependence of two baryon-to-meson ratios \bar{\Lambda}/K_{S}^{0} and \Omega/\phi on p_{T}, collision centrality and collision energy by the property of quark p_{T} spectra at hadronization. We derive the analytic relations between R_{CP} of hadrons and those of quarks, and we use them to naturally explain the species and p_{T} dependence of R_{CP} of those strange hadrons.

hep-ph↗

arXiv2022

Energy Dependence of the Breit-Wheeler process in Heavy-Ion Collisions and its Application to Nuclear Charge Radius Measurements

The collision energy dependence of the cross section and the transverse momentum distribution of dielectrons from the Breit-Wheeler process in heavy-ion collisions are computed in the lowest-order QED and found to be sensitive to the nuclear charge distribution and the infrared-divergence of the ultra-Lorentz boosted Coulomb field. Within a given experimental kinematic acceptance, the cross section is found to increase while the pair transverse momentum ($\sqrt{\langle p_{T}^{2} \rangle}$) decreases with increasing beam energy. We demonstrate that the transverse-momentum component of Weizsacker-Williams photons is due to the finite extent of the charge source and electric field component in the longitudinal direction. We further clarify the connection between the nuclear charge distribution and the kinematics of produced $e^+e^-$ from the Breit-Wheeler process, and propose a criterion for the validity of the Breit-Wheeler process in relativistic heavy-ion collisions. Following this approach we demonstrate that the experimental measurements of the Breit-Wheeler process in ultra-relativistic heavy-ion collisions can be used to quantitatively constrain the nuclear charge radius. The extracted parameters show sensitivity to the impact parameter dependence, and can be used to study the initial-state and final-state effects in hadronic interactions.

nucl-th↗

arXiv2016

Production of the $X_b$ in $Υ(5S, 6S)\to γX_b$ radiative decays

In this work, we investigate the production of $X_b$ in the process $Υ(5S,6S)\to γX_b$, where $X_b$ is assumed to be the counterpart of $X(3872)$ in the bottomonium sector as a $B {\bar B}^*$ molecular state. We use the effective Lagrangian based on the heavy quark symmetry to explore the rescattering mechanism and calculate their production ratios. Our results have shown that the production ratios for the $Υ(5S,6S) \to γX_b$ are orders of $10^{-5}$ with reasonable cutoff parameter range $α\simeq 2\sim 3$. The sizeable production ratios may be accessible at the future experiments like forthcoming BelleII, which will provide important clues to the inner structures of the exotic state $X_b$.

hep-ph↗