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Related papers: Higher Twist Effects in Photon-Photon Collisions

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We quantify the importance of dynamical spin effects in the holographic light-front wavefunctions of the pion, kaon, $\eta$ and $\eta^\prime$. Using a universal AdS/QCD scale and constituent quark masses, we find that such effects are…

High Energy Physics - Phenomenology · Physics 2018-08-22 Mohammad Ahmady , Chandan Mondal , Ruben Sandapen

In the era of precision measurements in high-energy heavy-ion physics, there is an increasing expectation towards phenomenological and theoretical studies to provide a better description of data. In recent years, multiple experiments have…

Nuclear Experiment · Physics 2026-04-09 Daniel Kincses , Emese Arpasi , Laszlo Kovacs , Marton Nagy , Mate Csanad

In this paper, we investigate the influence of coherent pion emission on long-range azimuthal correlations in relativistic proton-proton collisions. We study the pion momentum distribution for a coherent source with both transverse and…

Nuclear Theory · Physics 2020-08-26 Peng Ru , Wei-Ning Zhang

We consider double-photon and bremsstrahlung mechanisms for the production of two charged pions in high-energy electron (or proton) scattering off a transversely polarised proton. Interference between the relevant amplitudes generates a…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Galynsky , E. Kuraev , P. Ratcliffe , B. Shaikhatdenov

Starting from the experimental evidence that high-energy nucleus-nucleus collisions cannot be described in terms of superpositions of elementary nucleon-nucleon interactions, we analyze the possibility that memory effects and long-range…

Nuclear Theory · Physics 2009-01-07 W. M. Alberico , A. Lavagno , P. Quarati

An investigation of high transverse momentum (high-$p_T$) photon triggered jets in proton-proton ($p$-$p$) and ion-ion ($A$-$A$) collisions at $\sqrt{s_{NN}} = 0.2$ and $5.02~\mathrm{TeV}$ is carried out, using the multistage description of…

The contribution of the higher-twist mechanism to the large-$p_T$ inclusive gluon production cross section in $\pi p$ collisions is calculated in case of the principle of maximum conformality and Brodsky-Lepage-Mackenzie approaches in the…

High Energy Physics - Phenomenology · Physics 2015-06-18 A. I. Ahmadov , C. Aydin , O. Uzun

We investigate the influence of medium corrections to the pion dispersion relation on the pion dynamics in intermediate energy heavy ion collisions. To do so a pion potential is extracted from the in-medium dispersion relation and used in…

Nuclear Theory · Physics 2008-11-26 C. Fuchs , L. Sehn , E. Lehmann , J. Zipprich , Amand Faessler

First we calculate cross section for the $\gamma p \to \omega p$ reaction from the threshold to very large energies. At low energies the pion exchange is the dominant mechanism. At large energies the experimental cross section can be well…

High Energy Physics - Phenomenology · Physics 2015-03-18 Anna Cisek , Piotr. Lebiedowicz , Wolfgang Schäfer , Antoni Szczurek

We study the frequency dependencies of the fermion and photon dressing functions in dynamical gap generation in graphene. We use a low energy effective QED-like description, but within this approximation, we include all frequency dependent…

Mesoscale and Nanoscale Physics · Physics 2018-03-14 M. E. Carrington , C. S. Fischer , L. von Smekal , M. H. Thoma

Based on the light-cone (LC) framework and the $k_T$ factorization formalism, the transverse momentum effects and the different helicity components' contributions to the pion form factor $F_{\pi}(Q^2)$ are recalculated. In particular, the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Xing-Gang Wu , Tao Huang

In this work, $\gamma^{(\ast)}\gamma^{(\ast)}$ interactions in electron-positron collisions are studied across both low- and high-energy regimes. The analysis includes contributions from the Vector Meson Dominance (VMD) model (via Reggeon…

High Energy Physics - Phenomenology · Physics 2025-09-01 G. Zardo Becker

Generalized distribution amplitudes (GDAs) of mesons can be probed by the reactions $e^- e^+ \to M_1 M_2 \gamma$, which are accessible at electron-positron colliders such as BESIII and Belle II. After discussing the neutral meson production…

High Energy Physics - Phenomenology · Physics 2024-04-10 Bernard Pire , Qin-Tao Song

Experimental data on transverse single-spin asymmetry, hyperon polarization and vector meson alignment in h+h, h+A and A+A-collisions have been analyzed. A new mechanism for the origin of single spin effects is proposed, which takes into…

High Energy Physics - Phenomenology · Physics 2007-11-05 V. V. Abramov

We investigate the production of pions in heavy-ion collisions in the energy range of $1$ - $2$ GeV/A. The dynamics of the nucleus-nucleus collisions is described by a set of coupled transport equations of the Boltzmann-Uehling-Uhlenbeck…

Nuclear Theory · Physics 2016-09-08 S. Teis , W. Cassing , M. Effenberger , A. Hombach , U. Mosel , Gy. Wolf

The subtle differences between positive and negative pion spectra can used be used to study the nature of the nuclear interaction region in heavy-ion collisions. Several large acceptance heavy ion experiments at facilities ranging from SIS,…

Nuclear Experiment · Physics 2014-08-07 D. Cebra , S. G. Brovko , C. E. Flores , B. A. Haag , J. L. Klay

The cross section for massive fermion production in two-photon collisions was examined at next-to-leading order in QCD/QED for general photon helicity. The delta function (virtual+soft) part of the differential cross section was…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Kamal , Z. Merebashvili

Motivated by the recent LHC observation of an excess of diphoton events around an invariant mass of 750 GeV, we discuss the possibility that this is due to the decay of a new scalar or pseudoscalar resonance dominantly produced via…

High Energy Physics - Phenomenology · Physics 2016-04-18 L. A. Harland-Lang , V. A. Khoze , M. G. Ryskin

In continuation of our perusal of the studies on transverse momentum spectra for the main varieties of secondaries from a consistent and comprehensive phenomenological approach, we propose to take up here -- after a successful completion of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Bhaskar De , S. Bhattacharyya

We point out that events associated with large $E_T$ direct photons in high-energy heavy-ion collisions can be used to study jet energy loss in dense matter. In such events, the $p_T$ spectrum of charged hadrons from jet fragmentation in…

High Energy Physics - Phenomenology · Physics 2009-10-28 Xin-Nian Wang , Zheng Huang , Ina Sarcevic