Related papers: Evidence for higher order QED in e+ e- pair produc…
Lowest order and higher order QED calculations have been carried out for the RHIC high mass e+ e- pairs observed by PHENIX with single ZDC triggers. The lowest order QED results for the experimental acceptance are about two standard…
A higher order QED calculation of the ultraperipheral heavy ion cross section for mu+ mu- pair production at RHIC and LHC is carried out. The so-called "Coulomb corrections" lead to an even greater percentage decrease of mu+ mu- production…
The STAR collaboration at RHIC is measuring the production of electron-positron pairs at small impact parameters, larger than but already close to the range, where the ions interact strongly with each other. We calculate the total cross…
This thesis presents a measurement of the cross-section of the purely electromagnetic production of $e^+e^-$ pairs accompanied by mutual nuclear Coulomb excitation $AuAu\to Au^*Au^*+e^+e^-$, in ultra-peripheral gold-gold collisions at RHIC…
The RHIC Beam Energy Scan focuses on the study of the QCD phase diagram --- temperature ($T$) vs. baryon chemical potential ($\mu_B$). The aim is to verify some predictions from QCD: that a cross-over occurs at $\mu_B$ = 0, that there…
The heavy ion cross section for continuum e+ e- pair production has been calculated to all orders in Z alpha. Comparison is made with available CERN SPS and RHIC STAR data. Computed cross sections are found to be reduced from perturbation…
The higher order quantum electrodynamics (QED) effect for vacuum pair production has been searched without success since 1954. In this paper, we show that the lowest order QED calculations for lepton pair vacuum production in heavy-ion…
Recent experimental results obtained in STAR experiment at the Relativistic heavy-ion collider (RHIC) with ion beams will be discussed. Investigations of different nuclear collisions in some recent years focus on two main tasks, namely,…
Recently, significant enhancements of $e^{+} e^{-}$ pair production at very low transverse momentum ($p_{T} < 0.15$ GeV/c) were observed by the STAR collaboration in peripheral hadronic A+A collisions. This excesses can not be described by…
A current focus at RHIC is the Beam Energy Scan to study the QCD phase diagram -- temperature ($T$) vs. baryon chemical potential ($\mu_{B}$). The STAR experiment has collected data for Au+Au collisions at $\sqrt{s_{NN}}=$ 7.7 GeV, 11.5…
The moments of proton and net-proton multiplicity distributions are observables expected to be sensitive to the QCD critical point and the nature of the QCD phase transition from QGP to hadron gas. Hyper-order cumulants are measured in wide…
The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is carrying out a spin physics program colliding transversely or longitudinally polarized proton beams at = 200-500 GeV to gain deeper…
In the search of QCD phase boundary and critical point, higher-order cumulants of conserved quantities are proposed as promising observables and have been studied extensively both experimentally and theoretically. In this paper we present…
In this report we present the first test run results from Au+Au collisions at $\sqrt{s_{NN}}$ = 9.2 GeV at RHIC. The large acceptance STAR detector has collected ~3k minimum bias collisions during this test run. The azimuthal anisotropy,…
Theoretical models suggest that the Quantum Chromo-Dynamics (QCD) phase diagram has a critical point demarcating the order of transition between the two phases: the hadron gas, in which the quarks are confined and the Quark-Gluon Plasma…
Recent progress in full jet reconstruction in heavy-ion collisions at RHIC makes it a promising tool for the quantitative study of the QCD at high energy density. Measurements in d+Au collisions are important to disentangle initial state…
Jets serve as an important tool to probe QCD both in the vacuum and in the hot and dense medium. The STAR experiment at RHIC plays a key role in studying QCD phenomena across different collision systems ($p$+$p$, $p$+A, A+A), offering…
The Beam Energy Scan program has been undertaken at the Relativistic Heavy Ion Collider (RHIC) to search for the QCD critical point. The presence of the critical point is expected to lead to non-monotonic behavior of several quantities.…
Top-quark pair production with an additional jet is an important signal and background process at the LHC. We present the next-to-leading order QCD calculation for this process and show results for integrated as well as differential cross…
One of the primary goals of high-energy heavy-ion collisions is to establish the QCD phase diagram and search for possible phase boundaries. The planned RHIC energy scan program will explore this exciting physics topic using heavy-ion…