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Related papers: Pre-equilibrium Photon and Dilepton Production

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We calculate dilepton spectra in heavy-ion collisions using a coarse-graining approach to the simulation of the created medium with the UrQMD transport model. This enables the use of dilepton-production rates evaluated in equilibrium…

High Energy Physics - Phenomenology · Physics 2016-02-17 H. van Hees , S. Endres , J. Weil , M. Bleicher

Heavy quarkonium production is an excellent tool to test both perturbative and non-perturbative QCD, as perturbative QCD can describe the heavy quark production process, while the formation of the quarkonium bound state involves…

Nuclear Experiment · Physics 2022-07-28 Theraa Tork

The drag and diffusion coefficients of heavy quarks (HQs) have been evaluated in the pre-equilibrium phase of the evolving fireball produced in heavy ion collisions at RHIC and LHC energies. The KLN and classical Yang-Mills spectra have…

Nuclear Theory · Physics 2015-08-05 Santosh K. Das , Marco Ruggieri , Surasree Mazumder , Vincenzo Greco , Jan-e Alam

After a brief review of the production dynamics of prompt single photons in hadron collisions, I summarize a new QCD calculation of the transverse momentum distribution of continuum prompt photon pairs produced by QCD subprocesses,…

High Energy Physics - Phenomenology · Physics 2014-11-18 Edmond L. Berger

A theoretical approach was developed to describe secondary particle emission in heavy ion collisions, with special regards to pre-equilibrium {\alpha}-particle production. Griffin's model of non-equilibrium processes is used to account for…

We calculate the cross section for inclusive prompt photon production in $\gamma\gamma$ collisions, i.e. the reaction $e^+e^-\to \gamma \gamma \to \gamma X$, in next-to-leading order QCD. We show that at LEP2 energies this cross section is…

High Energy Physics - Phenomenology · Physics 2014-11-17 L. E. Gordon , J. K. Storrow

The effects of multiple interactions in colliding particles (e.g. in nucleus-nucleus collisions) are modeled using the light-cone dipole approach. Guided by the abelian analogue of multi-photon interactions in the production of a pair of…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Z. Kopeliovich , Ivan Schmidt , A. V. Tarasov , O. O. Voskresenskaya

Perturbative analysis of parton kinetics for high energy nuclear collisions shows, that thermal equilibration of gluons happens very fast, while quark production is much slower. A simple 'minimal model' is proposed which includes only…

High Energy Physics - Phenomenology · Physics 2009-10-22 E. Shuryak , L. Xiong

Recent classical-statistical numerical simulations have established the "bottom-up" thermalization scenario of Baier et al. as the correct weak coupling effective theory for thermalization in ultrarelativistic heavy-ion collisions. We…

Nuclear Theory · Physics 2017-05-17 J. Berges , K. Reygers , N. Tanji , R. Venugopalan

We propose a new complete method, based on the Wigner distributions of photons, how to calculate differential distributions of dileptons created via photon-photon fusion in semicentral ($b<2R_A$) $AA$ collisions. The formalism is used to…

High Energy Physics - Phenomenology · Physics 2021-02-03 Mariola Kłusek-Gawenda , Wolfgang Schäfer , Antoni Szczurek

We investigate the processes leading to phase-space equilibration of parton distributions in nuclear interactions at collider energies. We derive a set of rate equations describing the chemical equilibration of gluons and quarks including…

Nuclear Theory · Physics 2008-11-26 T. S. Biro , E. van Doorn , B. Mueller , M. H. Thoma , X. N. Wang

We study the production and the evolution of quark-gluon plasma expected to be formed in ultra relativistic heavy-ion collisions, within the color flux-tube model. We introduce the gluonic component in the Boltzmann equation, which we solve…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gouranga C Nayak , V. Ravishankar

We introduce distribution functions for quarks and gluons in the Glasma and discuss how they satisfy various relationships of statistical physics. We use these distributions to compute photon production in the early stages of heavy ion…

High Energy Physics - Phenomenology · Physics 2015-06-19 Larry McLerran , Bjoern Schenke

The vacuum parton creation in quickly varying external fields is studied at the time scale of order 1 fm/$c$ typical for the quark-gluon plasma formation and thermalization. To describe the pre-equilibrium evolution of the system the…

Nuclear Theory · Physics 2009-11-10 A. V. Prozorkevich , S. A. Smolyansky , V. V. Skokov , E. E. Zabrodin

Quarkonium production in high-energy hadronic collisions is a useful tool to investigate fundamental aspects of Quantum Chromodynamics, from the proton and nucleus structure to deconfinement and the properties of the Quark Gluon Plasma…

Nuclear Experiment · Physics 2024-11-26 L. Massacrier

This paper investigates the transverse momentum broadening effect for electromagnetic production of dileptons in ultra-peripheral heavy ion collisions accompanied by nuclear dissociation. The electromagnetic dissociation probability of…

High Energy Physics - Phenomenology · Physics 2020-06-15 James Daniel Brandenburg , Wei Li , Lijuan Ruan , Zebo Tang , Zhangbu Xu , Shuai Yang , Wangmei Zha

In the canonical picture of the evolution of the quark-gluon plasma during a high-energy heavy-ion collision, quarks are produced in two waves. The first is during the first fm/c of the collision, when gluons thermalize into the QGP. After…

Nuclear Theory · Physics 2015-05-30 Scott Pratt

Using the Bayesian calibrated iEBE-MUSIC framework, we compute the production of electromagnetic radiation from hot hadronic matter at finite baryon density. Results for thermal photon and thermal dilepton yields are obtained by folding…

Nuclear Theory · Physics 2025-09-04 Xiang-Yu Wu , Charles Gale , Sangyong Jeon , Jean-François Paquet , Björn Schenke , Chun Shen

In two different phase transition models of nuclear fragmentation we show that the emission of pre-equilibrium particles and mixing of events from different classes cannot be ignored in the analysis of nuclear fragmentation data in terms of…

Nuclear Theory · Physics 2008-11-26 Wolfgang Bauer , Alexander Botvina

Electromagnetic (EM) probes, including photons and dileptons, do not interact strongly after their production in heavy-ion collisions, allowing them to carry undistorted information from their points of origin. This makes them powerful…

Nuclear Theory · Physics 2025-03-13 Lipei Du