{
  "bibcode": "2019GCN.25485....1W",
  "body": "X. Wang (THU), S. Antier (APC), M. Coughlin (Caltech),  W. Li (THU), X. Zhang (THU), \r\nJ. Mo (THU), G. Xi (THU), J. Bai (Yunnan Obs), S. Basa (LAM),  E. Bertin (IAP), \r\nM. Blazek (HETH/IAA-CSIC), Michel Boer (Artemis), A. Coleiro (APC), N. Christensen (Artemis), \r\nS. Ehgamberdiev (UBAI), D. A. Kann (HETH/IAA-CSIC), A. Klotz (IRAP), D. Coward (OzGrav-UWA), \r\nD. Corre (LL), J.G. Ducoin (LAL), B. Gendre (OzGrav-UWA), P. Hello (LAL),  L. Hu (PMO), C. Lachaud (APC), \r\nX. Jiang (NAOC), N. Leroy (LAL), B. Li (PMO),  W. Lin (THU),  D. Mirzaqulov (UBAI), \r\nT. Sun (PMO), C. Thoene (HETH/IAA-CSIC), D. Turpin (NAOC), L. Wang (Texas University/PMO), \r\nA. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), X.  Wu (PMO), H. Zhao (PMO), X. Zeng (XAO),\r\nJ. J. Zhang (YNAO), J. C. Zhang (THU):\r\n\r\nReport on behalf of AOGOT (All-sky Observations of Gravitational Optical Transients) and Grandma joint collaborations:\r\n\r\nUsing the MegaPrime/MegaCam instrument (1x1 deg FOV) at the\r\nCanada-France-Hawaii Telescope, we observed the candidate AT2019npv\r\nreported by Goldstein et al (GCN 25393) close to a galaxy at z=0.056\r\n(Jonker et al, GCN 25454), which was a candidate electromagnetic\r\ncounterpart of the GW event S190814bv (LIGO/Virgo Collaboration,\r\nGCN 25324, GCN. 25333).\r\n\r\nMultiple images were obtained with the CFHT for this object\r\nin g(210sx2), r(240sx2) and i(300sx2) bands beginning at 2019-08-24 13:08\r\nUTC. Using references from the DECam Legacy Survey (DECaLS), we performed\r\nimage differencing in g and r-bands, with a low significance detection in\r\ng-band and an r-band estimate of r_AB = 23.0+-0.05 mag (i-band has a\r\nsignificant detection, but the reference is not available and therefore the\r\nnumbers are unreliable).\r\n\r\nThis object has been ruled out by different spectroscopic observations\r\nand photometric archival analysis as being related to the LIGO/Virgo\r\nGW candidate (GCN25468, GCN25475, GCN25478).\n\nGCN OPS NOTE(27aug19): Per author's request, the last reference in the\nlast sentence was changed from \"GCN5478\" to \"GCN25478\"; and C. Corre\nwas added to the author list.]",
  "circularId": 25485,
  "createdOn": 1566893100000,
  "email": "wang_xf@mail.tsinghua.edu.cn",
  "subject": "LIGO/Virgo S190814bv: CFHTphotometryof AT2019npv",
  "submitter": "Xiaofeng Wang at Tsinghua University  <wang_xf@mail.tsinghua.edu.cn>",
  "eventId": "LIGO/Virgo S190814bv"
}