Search for the rare decay $D^0\to \hat{I}{¼}^{+}\hat{I}{¼}^{-}$

Abstract

A search for the rare decay $D^0\to \hat{I}{¼}^{+}\hat{I}{¼}^{-}$is performed using a data sample, corresponding to an integrated luminosity of 0.9 fb${}^{-1}$, of $pp$ collisions collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The observed number of events is consistent with the background expectations and corresponds to an upper limit of \mbox{$\mathcal{B}(D^0\to \hat{I}{¼}^{+}\hat{I}{¼}^{-})<6.2(7.6)\times 10^{-9}$} at \mbox{90%} \mbox{(95%)} confidence level. This result represents an improvement of more than a factor twenty with respect to previous measurements.

22 pages, 8 figures, Submitted to Physics Letters B