arXiv subjects

Mehmet Cem Güçlü

Publications and source records attributed to Mehmet Cem Güçlü.

3 recordsLinked to original sources

arXiv2026

Neutron tagging of heavy lepton pair production at RHIC and LHC energies

We calculated cross sections for $γγ\rightarrow \ell^+\ell^-$ ($\ell=e,μ,τ$) production in ultraperipheral gold and lead collisions and compare our results with recent measurements from the STAR, ALICE, ATLAS, and CMS experiments at center of mass energies $\sqrt{s_{NN}}=200$ GeV, $\sqrt{s_{NN}}=2.76 $ TeV, and $\sqrt{s_{NN}}=5.02$ TeV. The calculations are performed within lowest order quantum electrodynamics (LO QED) using a Monte Carlo technique for calculating the impact parameter dependent probability, and subsequently combined with neutron emission probabilities associated with Coulomb excitation of the nuclei. These neutron emission scenarios are modeled using a Poisson statistics, allowing the cross sections to be categorized into experimentally relevant neutron classes: 0n0n, 0n1n, 1n1n, 0nXn, XnXn, and inclusive (0n0n+0nXn+XnXn) production. To enable a direct comparison with experiments, fiducial phase space restrictions corresponding to the acceptance of each detector are implemented.

hep-ph↗

arXiv2023

Enhancements of electron-positron pair production at very low transverse momentum in peripheral hadronic A + A collisions

The STAR collaboration has observed an excess production of electron-positron pairs which have transverse momenta pperp < 150 MeV/c in peripheral gold-gold and uranium-uranium collisions. ALICE has also reported on an excess of mu mu pairs at low pperp in very peripheral lead-lead collisions at a center-of-mass energy of 2.76 TeV/nucleon pair. In literature, there are number of studies about the electromagnetic lepton pair productions in peripheral heavy-ion collisions. Almost all of them have a prediction that unitary is violated in these high energies so that probability of producing electron-positron pairs is greater than one. It is clear that at RHIC and LHC energies, probabilities of producing electron-positron pairs for impact parameters smaller than Compton-wavelength of electron is greater than one. This means that for small impact parameters where the electric field is strongest multiple electron-positron pair productions is inescapable and it must be included in calculations. In literature, there are number of explanations about the pperp broadening however none of them has included the multi-pair production processes in their calculations. The aim of this paper is to show that electron-positron multi-pair production cross section is large and it can not be ignored in calculations.

hep-ph↗

arXiv2020

Multiple scattering production of lepton-pairs in ultraperipheral heavy-ion collisions

Ultra-relativistic peripheral collisions of heavy ions at LHC can produce copies of numbers of lepton pairs via the two-photon process. Since the energy of the heavy ions is so high, multi-pair production cross-sections of the light leptons especially electrons are quite large so that it is possible to measure them experimentally. To calculate the multi-pair production probabilities, first, we should have an impact parameter dependence cross-section. We have obtained a well-behaved impact parameter dependence cross-section and by using the Monte-Carlo methods, we have calculated multi-pair production cross-sections of electrons and muons in Pb-Pb heavy-ion collisions at LHC energies. We have also used some experimental restrictions in our calculation to compare our findings with the experimental results.

hep-ph↗