Measurement of $CP$ observables in $B_s^0 \rightarrow D_s^{\mp}K^{\pm}$ at LHCb

The time-dependent CP-violating observables accessible through Bs->DsK decays have been measured for the first time using data corresponding to an integrated luminosity of 1 inverse fb collected in 2011 by the LHCb detector. Using these observables, the CKM angle gamma is determined to be (115 -43 +28) modulo 180 degrees at 68% CL, where the uncertainty contains both statistical and systematic components.