Determining the upper limit of Γee for the Y (4260)
نویسندگان
چکیده
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 240 eV 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.
منابع مشابه
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.
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متن کاملar X iv : h ep - p h / 05 07 17 7 v 1 1 4 Ju l 2 00 5 Possible Molecular Structure of the Newly Observed Y ( 4260 ) March 5 , 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 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 Y (4260) → π + π − J/ψ mode i...
متن کاملar 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 ...
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