We report a sensitive study of measuring $bto sgamma$ photon polarisation in $D^{0}to K_1(1270)^-e^+ u_e$ with an integrated luminosity of $mathcal L$ = 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 $D^{0}to K_1(1270)^-e^+ u_e$ are expected. Based on a fast simulation software package, the statistical sensitivity for the ratio of up-down asymmetry is estimated to be $1.5times 10^{-2}$ by performing a two-dimensional angular analysis in $D^{0}to K_1(1270)^-e^+ u_e$. Combining with measurements of up-down asymmetry in $Bto K_1gamma$, the photon polarisation in $bto sgamma$ can be determined model-independently.
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