TITLE: GCN CIRCULAR NUMBER: 26430 SUBJECT: LIGO/Virgo S191213g: Pan-STARRS1 previous detections of ZTF19acykzsk DATE: 19/12/15 00:29:52 GMT FROM: Ken Smith at Queen's University Belfast K. W. Smith, S. J. Smartt, D. R. Young, S. Srivastav, J. Gillanders, O. McBrien, P. Clark, M. Fulton (Queen's University Belfast), M. Huber, K. C. Chambers, H. Flewelling, M. Willman, A. Schultz, E. Magnier, C. Waters, J. Bulger, R. J. Wainscoat (IfA, Hawaii), D. Wright (Univ. of Minnesota) report: Following on from Andreoni et al. (GCN 26424), we report previous Pan-STARRS1 (Chambers et al. 2016) detections of transient ZTF19acykzsk on 2019 December 12. We have 4 detections (PS19heq) at the location of the transient (RA = 02:11:37.08, Dec = +34:02:28.8) as detailed below, all in the PS1 w-band filter. Two of the detections are before the trigger time of S191213g and the other two are from after the event. We therefore do not believe this object is associated with the event. mjd | mag | dmag 58829.3649797 | 19.05 | 0.04 58829.3735363 | 19.00 | 0.05 58830.3920557 | 18.88 | 0.09 58830.3980885 | 18.88 | 0.05 Objects promoted in PS1 are automatically submitted to the TNS. In this case PS19heq was registered as AT2019wqj, but of course, we acknowledge this as a ZTF discovery. The TNS report was also submitted after the GCN 26424 had been sent.