中国物理学会高能物理分会第十三届全国粒子物理学术会议（2021）

We report a sensitive study of measuring b→sγ photon polarisation in D0→K1(1270)−e+νe with an integrated luminosity of L= 1 ab−1 at a center-of-mass energy of 3.773 GeV at future Super Tau Charm Facility. More than 61,000 signals of D0→K1(1270)−e+νe are expected. Based on a fast simulation software package, the statistical sensitivity for the ratio of up-down asymmetry is estimated to be 1.5×10−2 by performing a two-dimensional angular analysis in D0→K1(1270)−e+νe. Combining with measurements of up-down asymmetry in B→K1γ, the photon polarisation in b→sγ can be determined model-independently.