First Experimental Study of Photon Polarization in Radiative Bs Decays
نویسنده
چکیده
The polarization of photons produced in radiative Bs decays is studied for the first time. The data are recorded by the LHCb experiment in pp collisions corresponding to an integrated luminosity of 3 fb−1 at center-of-mass energies of 7 and 8 TeV. A time-dependent analysis of the Bs → φγ decay rate is conducted to determine the parameter AΔ, which is related to the ratio of rightover left-handed photon polarization amplitudes in b → sγ transitions. A value of AΔ 1⁄4 −0.98þ0.46 −0.52 −0.20 is measured. This result is consistent with the standard model prediction within 2 standard deviations.
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تاریخ انتشار 2017