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Title: Decays of the X(3872) and the {chi}{sub c1}(2P) charmonium state

Abstract

We reexamine the rescattering mechanism for the X(3872), as a candidate for the 2P charmonium state {chi}{sub c1}(2P), decaying to J/{psi}{rho}({omega}) through exchanging D{sup (*)} mesons between intermediate states D(D) and D*(D*). We evaluate the dispersive part, as well as the absorptive one, of the rescattering amplitude and find that the contribution from the dispersive part is dominant even when X(3872) lies above the threshold of the neutral channel th{sub n}=m{sub D{sup 0}}+m{sub D*{sup 0}}. We predict R{sub {rho}}{sub /{omega}}{approx_equal}1 for the m{sub X} region scanned by experiments. Meanwhile, we also estimate the rate of X{yields}D{sup 0}D{sup 0}{pi}{sup 0}. Our results favor a charmonium interpretation of X(3872) when it lies slightly below the threshold of D{sup 0}D*{sup 0}. Furthermore, we evaluated the width of X{yields}J/{psi}{rho} with the help of a phenomenological effective coupling constant g{sub X}, and find the total width of X(3872) to be in the range of 1-2 MeV.

Authors:
 [1];  [1];  [2]
  1. Department of Physics, Peking University, Beijing 100871 (China)
  2. (World Laboratory), Beijing 100080 (China)
Publication Date:
OSTI Identifier:
20929541
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.75.114002; (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; CHARMONIUM; COUPLING CONSTANTS; D MESONS; INTERMEDIATE STATE; J PSI-3097 MESONS; PARTICLE DECAY; RESCATTERING; RHO-770 MESONS

Citation Formats

Meng Ce, Chao, K.-T., and China Center of Advanced Science and Technology. Decays of the X(3872) and the {chi}{sub c1}(2P) charmonium state. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.114002.
Meng Ce, Chao, K.-T., & China Center of Advanced Science and Technology. Decays of the X(3872) and the {chi}{sub c1}(2P) charmonium state. United States. doi:10.1103/PHYSREVD.75.114002.
Meng Ce, Chao, K.-T., and China Center of Advanced Science and Technology. Fri . "Decays of the X(3872) and the {chi}{sub c1}(2P) charmonium state". United States. doi:10.1103/PHYSREVD.75.114002.
@article{osti_20929541,
title = {Decays of the X(3872) and the {chi}{sub c1}(2P) charmonium state},
author = {Meng Ce and Chao, K.-T. and China Center of Advanced Science and Technology},
abstractNote = {We reexamine the rescattering mechanism for the X(3872), as a candidate for the 2P charmonium state {chi}{sub c1}(2P), decaying to J/{psi}{rho}({omega}) through exchanging D{sup (*)} mesons between intermediate states D(D) and D*(D*). We evaluate the dispersive part, as well as the absorptive one, of the rescattering amplitude and find that the contribution from the dispersive part is dominant even when X(3872) lies above the threshold of the neutral channel th{sub n}=m{sub D{sup 0}}+m{sub D*{sup 0}}. We predict R{sub {rho}}{sub /{omega}}{approx_equal}1 for the m{sub X} region scanned by experiments. Meanwhile, we also estimate the rate of X{yields}D{sup 0}D{sup 0}{pi}{sup 0}. Our results favor a charmonium interpretation of X(3872) when it lies slightly below the threshold of D{sup 0}D*{sup 0}. Furthermore, we evaluated the width of X{yields}J/{psi}{rho} with the help of a phenomenological effective coupling constant g{sub X}, and find the total width of X(3872) to be in the range of 1-2 MeV.},
doi = {10.1103/PHYSREVD.75.114002},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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  • The {sup 1}D{sub 2} charmonium assignment for the X(3872) meson is considered, as prompted by a recent result from the BABAR Collaboration, favoring 2{sup -+} quantum numbers for X. It is shown that established properties of X(3872) are in a drastic conflict with the {sup 1}D{sub 2} cc assignment.