TITLE: GCN CIRCULAR NUMBER: 29313 SUBJECT: ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT DATE: 21/01/17 18:10:08 GMT FROM: Anna Ho at UC Berkeley A. Y. Q. Ho (UC Berkeley) reports on behalf of the Zwicky Transient Facility collaboration: We obtained a target-of-opportunity observation of ZTF21aaeyldq/AT2021any (Ho et al., GCN 29305) with the Neil Gehrels Swift Observatory starting at UT 2021-01-17 (02h29), which is 0.81d after the first optical detection. We detected X-ray emission at the transient position with a count rate 0.0067 ct/s. Assuming a neutral hydrogen column density n_H = 8.12E20/cm2 (Willingale et al. 2013) and a power-law spectrum with photon index 2, the unabsorbed flux is 2.9E-13 erg/cm^2/s. At z=2.514 (A. de Ugarte Postigo et al., GCN 29307) the luminosity is 1.5E46 erg/s, typical of GRB afterglows at this epoch. Further monitoring is planned, and we thank the Swift team for rapidly scheduling and executing our observations. -- Anna Ho