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Title: Azimuthal dependence of the heavy quark initiated contributions to DIS

Abstract

We analyze the azimuthal dependence of the heavy-quark-initiated contributions to the lepton-nucleon deep inelastic scattering (DIS). First we derive the relations between the parton-level semi-inclusive structure functions and the helicity {gamma}*Q cross sections in the case of arbitrary values of the heavy quark mass. Then the azimuth-dependent O({alpha}{sub s}) lepton-quark DIS is calculated in the helicity basis. Finally, we investigate numerically the properties of the cos{phi} and cos2{phi} distributions caused by the photon-quark scattering (QS) contribution. It turns out that, contrary to the basic photon-gluon fusion (GF) component, the QS mechanism is practically cos2{phi}-independent. This fact implies that measurements of the azimuthal distributions in charm leptoproduction could directly probe the charm density in the proton.

Authors:
;  [1]
  1. Yerevan Physics Institute, Alikhanian Br.2, 375036 Yerevan (Armenia)
Publication Date:
OSTI Identifier:
20933225
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.75.014010; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; B QUARKS; C QUARKS; CROSS SECTIONS; DEEP INELASTIC SCATTERING; GLUONS; HELICITY; LEPTONS; MASS; PHOTONS; PROTONS; STRUCTURE FUNCTIONS; T QUARKS

Citation Formats

Ananikyan, L. N., and Ivanov, N. Ya.. Azimuthal dependence of the heavy quark initiated contributions to DIS. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.014010.
Ananikyan, L. N., & Ivanov, N. Ya.. Azimuthal dependence of the heavy quark initiated contributions to DIS. United States. doi:10.1103/PHYSREVD.75.014010.
Ananikyan, L. N., and Ivanov, N. Ya.. Mon . "Azimuthal dependence of the heavy quark initiated contributions to DIS". United States. doi:10.1103/PHYSREVD.75.014010.
@article{osti_20933225,
title = {Azimuthal dependence of the heavy quark initiated contributions to DIS},
author = {Ananikyan, L. N. and Ivanov, N. Ya.},
abstractNote = {We analyze the azimuthal dependence of the heavy-quark-initiated contributions to the lepton-nucleon deep inelastic scattering (DIS). First we derive the relations between the parton-level semi-inclusive structure functions and the helicity {gamma}*Q cross sections in the case of arbitrary values of the heavy quark mass. Then the azimuth-dependent O({alpha}{sub s}) lepton-quark DIS is calculated in the helicity basis. Finally, we investigate numerically the properties of the cos{phi} and cos2{phi} distributions caused by the photon-quark scattering (QS) contribution. It turns out that, contrary to the basic photon-gluon fusion (GF) component, the QS mechanism is practically cos2{phi}-independent. This fact implies that measurements of the azimuthal distributions in charm leptoproduction could directly probe the charm density in the proton.},
doi = {10.1103/PHYSREVD.75.014010},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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