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Title: Radiative Decays and the Nature of Heavy Quarkonia

Abstract

We argue that the photon spectra in radiative decays of various heavy quarkonium states provide important information on their nature. If two of these states are in the strong coupling regime, we are able to produce a parameter-free model-independent formula, which holds at next-to-leading order and includes both direct and fragmentation contributions. When the formula is checked against recent CLEO data it favors {upsilon}(2S) and {upsilon}(3S) in the strong coupling regime and disfavors {upsilon}(1S) in it.

Authors:
;  [1]
  1. Departament d'Estructura i Constituents de la Materia, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona, Catalonia (Spain)
Publication Date:
OSTI Identifier:
20778826
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.96.111801; (c) 2006 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; CESR STORAGE RING; FRAGMENTATION; MESONS; MULTIPARTICLE SPECTROMETERS; PARTICLE IDENTIFICATION; PHOTONS; QUANTUM CHROMODYNAMICS; QUARKONIUM; RADIATIVE DECAY; RESONANCE PARTICLES; STRONG-COUPLING MODEL

Citation Formats

Garcia i Tormo, Xavier, and Soto, Joan. Radiative Decays and the Nature of Heavy Quarkonia. United States: N. p., 2006. Web. doi:10.1103/PHYSREVLETT.96.1.
Garcia i Tormo, Xavier, & Soto, Joan. Radiative Decays and the Nature of Heavy Quarkonia. United States. doi:10.1103/PHYSREVLETT.96.1.
Garcia i Tormo, Xavier, and Soto, Joan. Fri . "Radiative Decays and the Nature of Heavy Quarkonia". United States. doi:10.1103/PHYSREVLETT.96.1.
@article{osti_20778826,
title = {Radiative Decays and the Nature of Heavy Quarkonia},
author = {Garcia i Tormo, Xavier and Soto, Joan},
abstractNote = {We argue that the photon spectra in radiative decays of various heavy quarkonium states provide important information on their nature. If two of these states are in the strong coupling regime, we are able to produce a parameter-free model-independent formula, which holds at next-to-leading order and includes both direct and fragmentation contributions. When the formula is checked against recent CLEO data it favors {upsilon}(2S) and {upsilon}(3S) in the strong coupling regime and disfavors {upsilon}(1S) in it.},
doi = {10.1103/PHYSREVLETT.96.1},
journal = {Physical Review Letters},
number = 11,
volume = 96,
place = {United States},
year = {Fri Mar 24 00:00:00 EST 2006},
month = {Fri Mar 24 00:00:00 EST 2006}
}
  • It will be shown that precise data on the photon spectrum of radiative decays of heavy quarkonia provides important information about their nature. It may eventually tell us whether a given state is bound due to a Coulomb-like potential or to a confining one.
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