ar X iv : h ep - p h / 05 07 02 5 v 2 9 A ug 2 00 5 The Possible Interpretations of Y ( 4260 )

ar X iv : h ep - p h / 05 07 02 5 v 1 2 J ul 2 00 5 The Possible Interpretations of Y ( 4260 )

The recently observed Y(4260) lies far above the decay threshold with a width less than 100 MeV. We argue that it’s very difficult to accommodate Y(4260) as a conventional cc̄ radial excitation or a D-wave state. It can’t be a hadronic molecule. Its special decay pattern does not favor the glueball interpretation. If Y(4260) is a scalar tetraquark, it must be produced by the I = 0 component of t...

ar X iv : h ep - p h / 05 07 17 7 v 2 2 4 Ju l 2 00 5 Possible Molecular Structure of the Newly Observed Y ( 4260 ) February 27 , 2008

We suggest that the newly observed resonance Y (4260) is a χ c − ρ 0 molecule. In this picture, we can easily interpret why Y (4260) → π + π − J/ψ has a larger rate than Y (4260) → D ¯ D which has not been observed, and we also predict another two possible partner states which may be observed in the future experiments. A direct consequence of this structure is that for this molecular structure ...

ar X iv : h ep - e x / 06 03 02 4 v 2 3 1 Ju l 2 00 6 Determining the upper limit of Γ ee for the Y ( 4260 )

By fitting the R values between 3.7 and 5.0 GeV measured by the BES collaboration, the upper limit of the electron width of the newly discovered resonance Y (4260) is determined to be 580 eV/c 2 at 90% C.L. Together with the BaBar measurement on Γee·B(Y (4260) → π + π − J/ψ), this implies a large decay width of Y (4260) → π + π − J/ψ final states.

ar X iv : h ep - p h / 02 05 07 5 v 1 8 M ay 2 00 2 CP Violation and the Search for New Physics ∗

We present an overview of CP violation in the Standard Model and Beyond, describing various possible sources of CP violation and how to search for them.

ar X iv : h ep - p h / 97 12 41 5 v 2 1 9 A ug 2 00 4 The ALLM parameterization of σ tot ( γ ∗ p ) an update