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Related papers: New QCD Effects at Large x

200 papers

Theoretical results for the cross section of heavy quark production near the threshold at NNLO of NRQCD are briefly overviewed.

High Energy Physics - Phenomenology · Physics 2007-05-23 A. A. Pivovarov

The `optimal' factorization scale $\mu_0$ is calculated for open heavy quark production. We find that the optimal value is $\mu_F=\mu_0\simeq 0.85\sqrt{p^2_T+m_Q^2} $; a choice which allows us to resum the double-logarithmic,…

High Energy Physics - Phenomenology · Physics 2017-03-07 E. G. de Oliveira , A. D. Martin , M. G. Ryskin

An increasingly large amount of quality fixed-target data on heavy-quark production at fixed-target energies is appearing. This data can provide information across a range of physics topics. The topics vary from investigations of QCD…

High Energy Physics - Experiment · Physics 2011-01-27 Jeffrey A. Appel

The spin-averaged binding energy and the hyperfine mass splitting of heavy-light mesons are investigated within the constituent quark model as a function of the inverse heavy-quark mass. It is shown that the so-called heavy-quark kinetic…

High Energy Physics - Phenomenology · Physics 2009-10-30 Silvano Simula

Bound states of heavy $\bar{q}q$ quarks are reviewed within the context of QCD, paying attention to what can be derived from the theory with a reasonable degree of rigour. This is compared with the results of semiclassical arguments. Among…

High Energy Physics - Phenomenology · Physics 2011-01-25 F. J. Yndurain

This paper explores a new mechanism for B production in which a b quark combines with a light parton from the hard-scattering process before hadronizing into the B hadron. This recombination mechanism can be calculated within perturbative…

High Energy Physics - Phenomenology · Physics 2011-01-27 Eric Braaten , Yu Jia , Thomas Mehen

We compute the heavy quark potential on configurations generated by the HEMCGC collaboration with dynamical staggered fermions at $6/g^2 = 5.6$ and with dynamical Wilson fermions at $6/g^2 = 5.3$. The computations are done on $16^3 \times…

High Energy Physics - Lattice · Physics 2010-11-01 U. M. Heller , Khalil M. Bitar , R. G. Edwards , A. D. Kennedy

We provide an update on QCD predictions for top-quark pair production close to threshold including bound state effects at the Large Hadron Collider. We compute the top-quark pair invariant mass distribution $d\sigma/dM_{t\bar{t}}$,…

High Energy Physics - Phenomenology · Physics 2025-05-19 M. V. Garzelli , G. Limatola , S. -O. Moch , M. Steinhauser , O. Zenaiev

The heavy quark production in ultraperipheral heavy ion collisions is investigated, in particular we focus on the results from the coherent interactions given by the two-photon process. One addresses the heavy quark total cross sections at…

High Energy Physics - Phenomenology · Physics 2009-01-07 V. P. Goncalves , M. V. T. Machado

During the last year, analytic expressions for the two-loop QCD corrections to the form factors for the vector, axial-vector, scalar and pseudo-scalar vertices involving a pair of heavy quarks, $Q \bar{Q}$, were calculated. The results are…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Bernreuther , R. Bonciani , T. Gehrmann , R. Heinesch , T. Leineweber , P. Mastrolia , E. Remiddi

We study the correlations of heavy quarks produced in relativistic heavy ion collisions and find them to be quite sensitive to the effects of the medium and the production mechanisms. In order to put this on a quantitative footing, as a…

High Energy Physics - Phenomenology · Physics 2015-05-30 Mohammed Younus , Umme Jamil , Dinesh K. Srivastava

The high parton density regime of the Quantum Chromodynamics (QCD), where the physics of parton saturation is expected to be dominant, is briefly discussed. Some phenomenological aspects of saturation are described, mainly focusing on…

High Energy Physics - Phenomenology · Physics 2011-01-25 V. P. Goncalves , M. V. T. Machado

The heavy quark-antiquark potential is accessible in perturbative QCD and in lattice simulations. The perturbative short-distance part of the potential is contructed via a restricted Fourier transform, covering the momentum region where…

High Energy Physics - Phenomenology · Physics 2011-08-30 Alexander Laschka , Norbert Kaiser , Wolfram Weise

In the heavy quark limit inclusive production rate of a heavy meson can be factorized, in which the nonperturbative effect related to the heavy meson can be characterized by matrix elements defined in the heavy quark effective theory. Using…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. P. Ma

We update the leading order in $\alpha_s$ QCD amplitude for deep exclusive neutrino and antineutrino production of a light meson on an unpolarized nucleon. The factorization theorems of the collinear QCD approach allow us to write the…

High Energy Physics - Phenomenology · Physics 2017-07-05 B. Pire , L. Szymanowski , J. Wagner

A general scheme is proposed here to describe the production of semi soft and soft quarks and gluons that form the bulk of the plasma in ultra relativistic heavy ion collisions. We show how to obtain rates as a function of time in a self…

Nuclear Theory · Physics 2009-11-07 Ambar Jain , V. Ravishankar

The double coherent and non-coherent diffractive production of heavy quark - antiquark pairs ($Q \bar{Q}$) in heavy ion scattering at high energies (LHC) is considered. The total and differential cross sections of these processes with the…

Multiple scattering, induced radiative energy loss and modified fragmentation functions of a heavy quark in nuclear matter are studied within the framework of generalized factorization in perturbative QCD. Modified heavy quark fragmentation…

High Energy Physics - Phenomenology · Physics 2014-11-18 Ben-Wei Zhang , Enke Wang , Xin-Nian Wang

We apply heavy-quark effective theory to separate long- and short-distance effects of heavy quarks in lattice gauge theory. In this approach, the inverse heavy-quark mass and the lattice spacing are treated as short distances, and their…

High Energy Physics - Lattice · Physics 2014-11-17 Junpei Harada , Shoji Hashimoto , Ken-Ichi Ishikawa , Andreas S. Kronfeld , Tetsuya Onogi , Norikazu Yamada

A review is given of latest results on tests of the flavour independence of strong interactions. Heavy quark mass effects are evident in the data and are now taken into account at next-to-leading order in QCD perturbation theory. The…

High Energy Physics - Experiment · Physics 2007-05-23 P. N. Burrows