arXiv subjects

Xiaoping Zhang

Publications and source records attributed to Xiaoping Zhang.

40 records · Page 3Linked to original sources

arXiv2013

Beam energy dependence of strange hadron production from STAR at RHIC

We present STAR measurements of K^{0}_{S}, ϕ, Λ, Ξ, and Ωat mid-rapidity from Au+Au collisions at \sqrt{s_{NN}} = 7.7, 11.5, 19.6, 27, and 39 GeV from the Beam Energy Scan (BES) program at the BNL Relativistic Heavy Ion Collider (RHIC). Nuclear modification factors and baryon-to-meson ratios are measured to understand recombination and parton energy loss mechanisms. Implications on partonic versus hadronic dynamics at low beam energies are discussed.

nucl-ex↗

arXiv2012

Probe the QCD phase diagram with phi-meson production in relativistic nuclear collisions at STAR

We present phi-meson transverse momentum distribution as well as its elliptic flow (v_{2}) measurements in Au + Au collisions at center-of-mass energy per nucleon pair \sqrt{s_{NN}} = 7.7, 11.5 and 39 GeV with the data taken from STAR experiment at RHIC in the year 2010. We discuss the energy dependence of phi-meson elliptic flow (v_{2}) and central-to-peripheral nuclear modification factors (R_{CP}). The v_{2} of phi-mesons are compared to those from other hadron species. The implications on partonic-hadronic phase transition are discussed.

nucl-ex↗

arXiv2012

Near-Infrared Super Resolution Imaging with Metallic Nanoshell Particle Chain Array

We propose a near-infrared super resolution imaging system without a lens or a mirror but with an array of metallic nanoshell particle chain. The imaging array can plasmonically transfer the near-field components of dipole sources in the incoherent and coherent manners and the super resolution images can be reconstructed in the output plane. By tunning the parameters of the metallic nanoshell particle, the plasmon resonance band of the isolate nanoshell particle red-shifts to the near-infrared region. The near-infrared super resolution images are obtained subsequently. We calculate the field intensity distribution at the different planes of imaging process using the finite element method and find that the array has super resolution imaging capability at near-infrared wavelengths. We also show that the image formation highly depends on the coherence of the dipole sources and the image-array distance.

physics.optics↗

arXiv2010

Effect of final state interactions on particle production in $d$+Au collisions at RHIC

We show that particle species dependence of enhanced hadron production at intermediate transverse momentum (p_{T}) for d+Au collisions at RHIC can be understood in terms of the hadronic rescatterings in the final state. A multiphase transport model (AMPT) with two different hadronization mechanisms: string fragmentation or parton coalescence, is used in our study. When the hadrons are formed from string fragmentation, the subsequent hadronic rescatterings will result in particle mass dependence of nuclear modification factor R_{CP}, which is consistent with the present experimental data. On the other hand, in the framework of parton coalescence, the mass dependence disappears and the strangeness plays an important role. Both mechanisms failed to reproduce the p_{T} dependence of R_{CP} of pion, indicating that initial-state effects might be also important in such collisions.

nucl-th↗