paper

Search for the Invisible Decay of $\jpsi$ in $I ¨ (2 S) \to I ¨ + I ¨ ^{-} J / I ¨ $

arXiv:0710.0039 · doi:10.1103/PhysRevLett.100.192001

Abstract

Using 14.0 million $I ¨ (2 S) e v e n t sco l l ec t e d w i t h t h e B E S - I I d e t ec t or, a se a r c h f or t h e d ec a y o f t h e$ \jpsi $t o anin v i s ib l e f ina l s t a t e in$ \psipto $i s p er f or m e d . T h e$ \jpsi $p e ak in t h e d i s t r ib u t i o n o f ma ssr eco i l in g a g ain s tt h e$ Ï^+Ï^- $i s u se d t o t a g$ Ï $in v i s ib l e d ec a y . N os i g na l i s f o u n d, an d an u pp er l imi t a tt h e 90$ 1.2\times 10^{-2} $f or t h er a t i o$ \frac{{\cal B}(\jpsi\ar {invisible})}{{\cal B}(\jpsi\arÎ¼^+Î¼^-)} $. T hi s i s t h e f i r s t se a r c h f or$ J/Ï$ decay to an invisible final state.

5 pages, 3 figures

Search for the Invisible Decay of $\jpsi$ in I¨(2S)→I¨+I¨−J/I¨

Abstract

Search for the Invisible Decay of $\jpsi$ in $I ¨ (2 S) \to I ¨ + I ¨ ^{-} J / I ¨ $