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Related papers: Isolated photon production and pion-photon correla…

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We discuss central-exclusive production (CEP) of photons via different fusion processes in the reaction $pp \to pp \gamma$ at high energies, available at RHIC and LHC, within the tensor-pomeron model. We consider two types of processes, the…

High Energy Physics - Phenomenology · Physics 2023-04-26 Piotr Lebiedowicz , Otto Nachtmann , Antoni Szczurek

In this paper we present a detailed comparison of the dijet production by photon -- photon, photon -- pomeron and pomeron -- pomeron interactions in $pp$, $pA$ and ${\rm AA}$ collisions at the LHC energy. The transverse momentum, pseudo --…

High Energy Physics - Phenomenology · Physics 2017-10-18 E. Basso , V. P. Goncalves , A. K. Kohara , M. S. Rangel

We investigate the theoretical uncertainty on the predictions for the photoproduction of $\rho$ and $J/\Psi$ states in nucleus-nucleus collisions at Run 2 LHC energies using the Color Dipole formalism. The results for rapidity distributions…

High Energy Physics - Phenomenology · Physics 2018-06-13 V. P. Goncalves , M. V. T. Machado , B. D. Moreira , F. S. Navarra , G. Sampaio dos Santos

The exclusive $\Upsilon$ photoproduction in proton-proton and proton - nucleus collisions at LHC energies is investigated using the color dipole formalism and considering different models for the $\Upsilon$ wave function and forward dipole…

High Energy Physics - Phenomenology · Physics 2015-06-22 V. P. Goncalves , B. D. Moreira , F. S. Navarra

The transverse energy ($E_\mathrm{T}^{\gamma}$) spectra of photons isolated from other particles are measured using proton-proton (pp) and lead-lead (PbPb) collisions at the LHC at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV with integrated…

High Energy Physics - Experiment · Physics 2020-07-22 CMS Collaboration

Collisions with Oxygen ions at the LHC opens the possibility of investigating the description of the QCD dynamics in an unexplored regime, complementary to those performed in $pp$, $pPb$ and $PbPb$ collisions. In this paper we estimate the…

High Energy Physics - Phenomenology · Physics 2023-06-07 Victor P. Goncalves , Bruno D. Moreira , Luana Santana

The cross sections for isolated and non-isolated prompt photon production with unpolarized hadron beams are studied at order $\alpha\alpha_s^2$. Two methods of performing the calculations are compared. One uses purely analytic techniques…

High Energy Physics - Phenomenology · Physics 2014-11-17 L. E. Gordon

We show that exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions can be systematically studied in QCD factorization approach if the photon's transverse momentum $q_T$ with respect to the colliding…

High Energy Physics - Phenomenology · Physics 2022-08-24 Jian-Wei Qiu , Zhite Yu

A measurement of the production of three isolated photons in proton-proton collisions at a centre-of-mass energy $\sqrt{s}$ = 8 TeV is reported. The results are based on an integrated luminosity of 20.2 fb$^{-1}$ collected with the ATLAS…

High Energy Physics - Experiment · Physics 2018-05-04 ATLAS Collaboration

We discuss central exclusive diffractive dihadron production in proton-proton collisions at high energies. The calculation is based on a tensor pomeron model and the amplitudes for the processes are formulated in an effective…

High Energy Physics - Phenomenology · Physics 2017-11-02 Piotr Lebiedowicz , Otto Nachtmann , Antoni Szczurek

We discuss coherent and incoherent photoproduction of $J/\Psi$ vector mesons in high energy heavy ion collisions. In a dipole picture for the photon both can be naturally related to the dipole cross section that is also probed in inclusive…

High Energy Physics - Phenomenology · Physics 2013-10-25 T. Lappi , H. Mäntysaari

The ALICE Collaboration reports three measurements in ultra-peripheral proton$-$lead collisions at forward rapidity. The exclusive two-photon process \ggmm and the exclusive photoproduction of J/$\psi$ are studied. J/$\psi$ photoproduction…

Nuclear Experiment · Physics 2024-01-09 ALICE Collaboration

A measurement of prompt photon-pair production in proton-proton collisions at $\sqrt{s}=13$ TeV is presented. The data were recorded by the ATLAS detector at the LHC with an integrated luminosity of 139 fb$^{-1}$. Events with two photons in…

High Energy Physics - Experiment · Physics 2021-12-08 ATLAS Collaboration

We study the transverse single spin asymmetry in direct photon production in pA collisions with incoming protons being transversely polarized. To facilitate the calculation, we formulate a hybrid approach in which the nucleus is treated in…

High Energy Physics - Phenomenology · Physics 2015-02-10 Andreas Schäfer , Jian Zhou

A measurement is presented of the exclusive and semi-exclusive production of charged pion pairs in proton-proton collisions, pp to p(p*) + $\pi^+\pi^-$ + p(p*) here the $\pi^+\pi^-$ pair is emitted at central rapidities, and the scattered…

High Energy Physics - Experiment · Physics 2020-04-03 CMS Collaboration

We investigate the photoproduction of $\rho$ mesons in ultraperipheral heavy ion collisions at RHIC and LHC energies in the dipole approach and within two phenomenological models based on the the Color Glass Condensate (CGC) formalism. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. P. Goncalves , M. V. T. Machado

The prompt photon production in p-p collisions at high energies is studied. Double-spin asymmetry of the process is calculated by using Monte Carlo code SPHINX. A possibility to discriminate the spin-dependent gluon distributions and to…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. P. Skoro , M. Zupan , M. V. Tokarev

Using the high energy color dipole approach, we study the exclusive photoproduction of lepton pairs. We use simple models for the elementary dipole-hadron scattering amplitude that captures main features of the dependence on atomic number…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. V. T. Machado

In order to establish links between p-wave pion production in nucleon-nucleon collisions and low energy three-nucleon scattering, an extensive programme of experiments on pion production is currently underway at COSY-ANKE. The final proton…

The dynamics of isolated-photon plus jet production in pp collisions at a centre-of-mass energy of 7 TeV has been studied with the ATLAS detector at the LHC using an integrated luminosity of 37 pb-1. Measurements of isolated-photon plus jet…

High Energy Physics - Experiment · Physics 2014-05-08 ATLAS Collaboration