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Title: Backward dilepton production in color dipole and parton models

Abstract

The Drell-Yan dilepton production at backward rapidities is studied in proton-nucleus collisions at Relativistic Heavy Ion Collider and LHC energies by comparing two different approaches: the k{sub T} factorization at next-to-leading order with intrinsic transverse momentum and the same process formulated in the target rest frame, i.e., the color dipole approach. Our results are expressed in terms of the ratio between p(d)-A and p-p collisions as a function of transverse momentum and rapidity. Three nuclear parton distribution functions are used: EKS (Eskola, Kolhinen, and Ruuskanen), EPS08, and EPS09 and, in both approaches, dileptons show sensitivity to nuclear effects, specially regarding the intrinsic transverse momentum. Also, there is room to discriminate between formalisms: the color dipole approach lacks soft effects introduced by the intrinsic k{sub T}. Geometric scaling GBW (Golec-Biernat and Wusthoff) and BUW (Boer, Utermann, and Wessels) color dipole cross section models and also a DHJ (Dumitru, Hayashigaki, and Jalilian-Marian) model, which breaks geometric scaling, are used. No change in the ratio between collisions is observed, showing that this observable is not changed by the particular shape of the color dipole cross section. Furthermore, our k{sub T} factorization results are compared with color glass condensate results at forward rapidities: themore » results agree at Relativistic Heavy Ion Collider although disagree at LHC, mainly due to the different behavior of target gluon and quark shadowing.« less

Authors:
;  [1]
  1. Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970 Porto Alegre, Rio Grande do Sul (Brazil)
Publication Date:
OSTI Identifier:
21409847
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 81; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.81.054015; (c) 2010 The American Physical Society; Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BROOKHAVEN RHIC; CERN LHC; COLLISIONS; COLOR MODEL; CONDENSATES; CROSS SECTIONS; DIPOLES; DISTRIBUTION FUNCTIONS; DRELL MODEL; FACTORIZATION; GLUONS; PARTICLE RAPIDITY; PROTON-NUCLEON INTERACTIONS; QUARK MODEL; QUARKS; SCALING; SENSITIVITY; TRANSVERSE MOMENTUM; ACCELERATORS; BARYON-BARYON INTERACTIONS; BOSONS; COMPOSITE MODELS; CYCLIC ACCELERATORS; FERMIONS; FUNCTIONS; HADRON-HADRON INTERACTIONS; HEAVY ION ACCELERATORS; INTERACTIONS; LINEAR MOMENTUM; MATHEMATICAL MODELS; MULTIPOLES; NUCLEON-NUCLEON INTERACTIONS; PARTICLE INTERACTIONS; PARTICLE MODELS; PARTICLE PROPERTIES; STORAGE RINGS; SYNCHROTRONS

Citation Formats

Gay Ducati, Maria Beatriz, and Graeve de Oliveira, Emmanuel. Backward dilepton production in color dipole and parton models. United States: N. p., 2010. Web. doi:10.1103/PHYSREVD.81.054015.
Gay Ducati, Maria Beatriz, & Graeve de Oliveira, Emmanuel. Backward dilepton production in color dipole and parton models. United States. https://doi.org/10.1103/PHYSREVD.81.054015
Gay Ducati, Maria Beatriz, and Graeve de Oliveira, Emmanuel. 2010. "Backward dilepton production in color dipole and parton models". United States. https://doi.org/10.1103/PHYSREVD.81.054015.
@article{osti_21409847,
title = {Backward dilepton production in color dipole and parton models},
author = {Gay Ducati, Maria Beatriz and Graeve de Oliveira, Emmanuel},
abstractNote = {The Drell-Yan dilepton production at backward rapidities is studied in proton-nucleus collisions at Relativistic Heavy Ion Collider and LHC energies by comparing two different approaches: the k{sub T} factorization at next-to-leading order with intrinsic transverse momentum and the same process formulated in the target rest frame, i.e., the color dipole approach. Our results are expressed in terms of the ratio between p(d)-A and p-p collisions as a function of transverse momentum and rapidity. Three nuclear parton distribution functions are used: EKS (Eskola, Kolhinen, and Ruuskanen), EPS08, and EPS09 and, in both approaches, dileptons show sensitivity to nuclear effects, specially regarding the intrinsic transverse momentum. Also, there is room to discriminate between formalisms: the color dipole approach lacks soft effects introduced by the intrinsic k{sub T}. Geometric scaling GBW (Golec-Biernat and Wusthoff) and BUW (Boer, Utermann, and Wessels) color dipole cross section models and also a DHJ (Dumitru, Hayashigaki, and Jalilian-Marian) model, which breaks geometric scaling, are used. No change in the ratio between collisions is observed, showing that this observable is not changed by the particular shape of the color dipole cross section. Furthermore, our k{sub T} factorization results are compared with color glass condensate results at forward rapidities: the results agree at Relativistic Heavy Ion Collider although disagree at LHC, mainly due to the different behavior of target gluon and quark shadowing.},
doi = {10.1103/PHYSREVD.81.054015},
url = {https://www.osti.gov/biblio/21409847}, journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 5,
volume = 81,
place = {United States},
year = {Mon Mar 01 00:00:00 EST 2010},
month = {Mon Mar 01 00:00:00 EST 2010}
}