FOCUS Document 877-v1

DocDB Home ]  [ Search ] [ Last 20 Days ] [ List Authors ] [ List Topics ] [ List Events ]

Observation of a 1750 MeV/c^2 Enhancement in the Diffractive Photoproduction of K^+K^-

Document #:
Document type:
Submitted by:
Eduardo Luiggi
Updated by:
Eduardo Luiggi
Document Created:
26 Aug 2005, 11:10
Contents Revised:
26 Aug 2005, 11:10
Metadata Revised:
03 Oct 2002, 11:15
Actually Revised:
26 Aug 2005, 11:13
Viewable by:
  • Public document
Modifiable by:
  • Same as Viewable by

Quick Links:
Latest Version

Using the FOCUS spectrometer with photon beam energies between 20 and 160 \gev, we confirm the existence of a diffractively photoproduced enhancement in $K^+K^-$ at 1750 \mevcc with nearly 100 times the statistics of previous experiments. Assuming this enhancement to be a single resonance with a Breit-Wigner mass shape, we determine its mass to be $1753.5\pm 1.5\pm 2.3$ \mevcc and its width to be $122.2\pm 6.2\pm 8.0$ \mevcc. We find no corresponding enhancement at 1750 \mevcc in $K^*K$, and again neglecting any possible interference effects we place limits on the ratio $\Gamma (X(1750) \to K^*K)/\Gamma (X(1750) \to K^+K^-)$. Our results are consistent with previous photoproduction experiments, but, because of the much greater statistics, challenge the common interpretation of this enhancement as the $\phi (1680)$ seen in $e^+e^-$ annihilation experiments.

Files in Document:
Journal References:
Published in hep-ex/0208027.
Published in Phys. Lett. B vol. 545 pg. 50.
DocDB Home ]  [ Search ] [ Last 20 Days ] [ List Authors ] [ List Topics ] [ List Events ]

DocDB Version 8.8.9, contact Document Database Administrators