English

Measurement of e^+e^- to pi^+pi^-J/psi Cross Section via Initial State Radiation at Belle

High Energy Physics - Experiment 2008-11-26 v2 High Energy Physics - Phenomenology

Abstract

The cross section for e^+e^- to pi^+pi^-J/psi between 3.8 and 5.5 GeV/c^2 is measured using a 548 fb^{-1} data sample collected on or near the Upsilon(4S) resonance with the Belle detector at KEKB. A peak near 4.25 GeV/c^2, corresponding to the so called Y(4260), is observed. In addition, there is another cluster of events at around 4.05 GeV/c^2. A fit using two interfering Breit-Wigner shapes describes the data better than one that uses only the Y(4260), especially for the lower mass side of the 4.25 GeV enhancement.

Keywords

Cite

@article{arxiv.0707.2541,
  title  = {Measurement of e^+e^- to pi^+pi^-J/psi Cross Section via Initial State Radiation at Belle},
  author = {Belle Collaboration and C. Z. Yuan},
  journal= {arXiv preprint arXiv:0707.2541},
  year   = {2008}
}

Comments

11 pages, 5 figures, 2 tables; version to appear in PRL