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Title: Time-odd distribution functions, breaking of long range correlations, and sudden entropy changes, in Drell-Yan high-energy processes

Abstract

Time-odd parton distribution functions in a Drell-Yan process are here studied by examining the evolution of the internal statistical properties of the interacting hadrons. Time-odd functions are shown to be a signature of the irreversible process in which a hadronic state characterized by long range correlation properties (hadronic phase) decays to produce a cloud of independent partons (partonic phase) because of initial/final state interactions. The relevant considered variable is the rate of increase of the entropy of the hadronic system. This quantity is shown to be roughly equal to the decay rate of the hadronic state. Conditions for getting a leading twist time-odd effect are established on this basis. Last, the relevant case of a large entropy increase associated with transverse-dominated initial/final state interactions is analyzed.

Authors:
 [1]
  1. Dipartimento di Chimica e Fisica per l'Ingegneria e per i Materiali, Universita di Brescia, I-25123 Brescia (Italy) and Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia (Italy)
Publication Date:
OSTI Identifier:
21020265
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.75.074005; (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; CORRELATIONS; DISTRIBUTION FUNCTIONS; DRELL MODEL; ENTROPY; FINAL-STATE INTERACTIONS; GLUONS; HADRONS; IRREVERSIBLE PROCESSES; PARTICLE DECAY; QUARKS

Citation Formats

Bianconi, A. Time-odd distribution functions, breaking of long range correlations, and sudden entropy changes, in Drell-Yan high-energy processes. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.074005.
Bianconi, A. Time-odd distribution functions, breaking of long range correlations, and sudden entropy changes, in Drell-Yan high-energy processes. United States. doi:10.1103/PHYSREVD.75.074005.
Bianconi, A. Sun . "Time-odd distribution functions, breaking of long range correlations, and sudden entropy changes, in Drell-Yan high-energy processes". United States. doi:10.1103/PHYSREVD.75.074005.
@article{osti_21020265,
title = {Time-odd distribution functions, breaking of long range correlations, and sudden entropy changes, in Drell-Yan high-energy processes},
author = {Bianconi, A.},
abstractNote = {Time-odd parton distribution functions in a Drell-Yan process are here studied by examining the evolution of the internal statistical properties of the interacting hadrons. Time-odd functions are shown to be a signature of the irreversible process in which a hadronic state characterized by long range correlation properties (hadronic phase) decays to produce a cloud of independent partons (partonic phase) because of initial/final state interactions. The relevant considered variable is the rate of increase of the entropy of the hadronic system. This quantity is shown to be roughly equal to the decay rate of the hadronic state. Conditions for getting a leading twist time-odd effect are established on this basis. Last, the relevant case of a large entropy increase associated with transverse-dominated initial/final state interactions is analyzed.},
doi = {10.1103/PHYSREVD.75.074005},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
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  • We extract the Boer-Mulders functions of valence and sea quarks in the proton from unpolarized p+D Drell-Yan data measured by the FNAL E866 Collaboration. Using these Boer-Mulders functions, we calculate the cos2{phi} asymmetries in unpolarized pp Drell-Yan processes, both for the FNAL E866/NuSea and the BNL Relativistic Heavy Ion Collider experiments. We also estimate the cos2{phi} asymmetries in the unpolarized pp Drell-Yan processes at GSI.
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