Updated limit for the $K_S^0\to \mu^+\mu^-$ decay

A search for the decay is performed using the data sample of pp collisions at TeV collected by the LHCb experiment at the Large Hadron Collider in 2012, corresponding to an integrated luminosity of 2.0 fb(−)(1). In the Standard Model, this decay is expected to be suppressed at a level below the current experimental sensitivity, but could be enhanced by new sources of CP violation. The observed number of candidates is compatible with the expected background and allows to set an upper limit at 95 (90)% confidence level. This limit improves the result published by LHCb using 1.0 fb(−)(1) of collisions collected in 2011 at TeV.