Abstract
The properties of the resonance are investigated in the decay process. The data sample was collected with the BABAR detector at the SLAC PEP-II asymmetric-energy collider operating at center-of-mass energies 10.58 and 10.54 GeV. The corresponding integrated luminosity is approximately . The spin of the is established to be . The existence of an -wave amplitude in the system is inferred, and its interference with the amplitude provides the first clear demonstration of the Breit-Wigner phase motion expected for the . The Legendre polynomial moment indicates the presence of a significant -wave amplitude for mass values above , and a dip in the mass distribution at approximately is interpreted as due to the coherent addition of a contribution to this amplitude. This would imply for the . Attempts at fitting the line shape yield unsatisfactory results, and this failure is attributed to interference effects associated with the amplitudes describing the and/or systems.
5 More- Received 12 March 2008
DOI:https://doi.org/10.1103/PhysRevD.78.034008
©2008 American Physical Society