{
  "bibcode": "2019GCN.25628....1W",
  "body": "J. Y. Wei (NAOC), X. H. Han (NAOC), N. Dagoneau (CEA/AIM), J. Wang (GXU),\nN. Leroy (CNRS/LAL)\n\non behalf of the SVOM Multi Messenger Astronomy and GWAC teams:\nhttp://www.svom.fr/en/svom-mma-and-gwac-team\n\nWe observed 9 sky regions (total: 1350 square degrees with overlaps)\nto cover the skymap of the advanced LIGO/Virgo trigger S190828j,\nwith SVOM/GWAC, at Xinglong Observatory equipped with a set of two\ntypes of wide angle cameras: FFOV cameras (FOV~900 square degrees/camera,\naperture = 3.5 cm) and JFOV cameras (FOV~150 square degrees/camera,\naperture = 18 cm). SVOM/GWAC currently comprises 4 FFOV cameras and\n16 JFOV cameras, working with unfiltered band. The observations are\noperated in time-series mode, taking one exposure every 25 seconds\n(20s exposure + 5s readout). We estimate a 19.6% prior probability\nthat the 9 observed and processed regions contain the true location of\nthe source. The images were taken between ~5.5 hours and ~13 hours after\nthe event trigger time.\n\nThe coordinates of the 9 sky regions and observation times are listed\nbelow:\n\nNo. Ra �Dec start-obs(UTC) �end-obs(UTC) ���Camera_TYPE\n\n1 01:43:32.26 64:07:03.00 2019-08-28 13:53:25 2019-08-28 16:51:08 JFOV\n2 00:07:40.03 51:45:14.40 2019-08-28 16:41:24 2019-08-28 16:44:15 JFOV\n3 00:13:04.03 64:02:39.84 2019-08-28 17:05:25 2019-08-28 17:22:48 JFOV\n4 21:27:48.00 47:17:53.52 2019-08-28 13:03:27 2019-08-28 13:05:53 JFOV\n5 20:43:28.32 -1:13:58.98 2019-08-28 13:20:46 2019-08-28 13:35:19 JFOV\n6 21:18:27.60 13:20:15.00 2019-08-28 16:08:33 2019-08-28 16:19:54 JFOV\n7 20:50:18.72 63:41:09.96 2019-08-28 13:30:52 2019-08-28 13:35:43 JFOV\n8 21:59:13.44 48:02:44.52 2019-08-28 13:40:52 2019-08-28 14:06:20 JFOV\n9 22:05:10.08 34:10:09.48 2019-08-28 12:08:19 2019-08-28 19:00:58 JFOV\n\nThe sky coverage map is available at: \nhttp://cmm.svom.cn/gwpub/O3/S190828j/S190828j.png \n(user:svomo3 pwd:gwo3)\n\nThe weather conditions were hazy during the observations. A 3 sigma \nlimiting magnitude of about 16.3 mag in R band was obtained in the single \nframes. No credible new source is detected by our online pipeline during \nfollow-up observations. A more detailed image analysis including\nco-addition is ongoing with our offline pipeline to search for transient\ncandidates.",
  "circularId": 25628,
  "createdOn": 1567514393000,
  "email": "nicolas.dagoneau@cea.fr",
  "subject": "LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations",
  "submitter": "Nicolas Dagoneau at CEA/IRFU/DAp/SVOM  <nicolas.dagoneau@cea.fr>",
  "eventId": "LIGO/Virgo S190828j"
}