{
  "bibcode": "2020GCN.26948....1X",
  "body": "L. P. Xin (NAOC), D. Turpin (CEA/AIM), X. H. Han (NAOC), \nP. Maggi (CNRS/ObAS), G. W. Li (NAOC)\n\nreport on behalf of the SVOM Multi Messenger Astronomy and GWAC teams\n(http://www.svom.fr/en/svom-mma-and-gwac-team):\n\nWe observed 24 (~3600 square deg) sky regions to cover the skymap of the\nadvanced LIGO/Virgo trigger S200128d  (GCN # 26906), with SVOM/GWAC,\nat Xinglong Observatory. SVOM/GWAC is equipped with two sets of\nwide angle cameras:\n- FFOV cameras (FOV~900 square degrees/camera, aperture = 3.5 cm),\n- JFOV cameras (FOV~150 square degrees/camera, aperture = 18 cm).\n\nSVOM/GWAC currently comprises 4 FFOV cameras and 16 JFOV cameras,\nworking in the unfiltered band. The observations are operated in\ntime-series mode, taking one exposure every 25 seconds\n(20s exposure + 5s readout). The observed and processed regions enclosed\nan estimated 41.5% of the probability of the advanced LIGO/Virgo skymap.\nImages were taken between ~ 1 day 8 hours and ~ 1 day 19 hours \nafter the GW trigger time. The coordinates of the 24 sky regions \nobserved and their observation times and covered probability are \nlisted below:\n\nId Ra           Dec         start (UTC)       end (UTC)         Proba. Cam.\n1  07:26:22.5  52:57:12 2020-01-29 10:55:07 2020-01-29 11:22:13 0.026 JFOV\n2  05:56:38.9  65:08:37 2020-01-29 11:06:26 2020-01-29 11:18:58 0.004 JFOV\n3  06:12:15.3  53:15:18 2020-01-29 11:09:16 2020-01-29 11:22:12 0.057 JFOV\n4  07:44:20.8  51:50:32 2020-01-29 11:25:03 2020-01-29 11:51:47 0.017 JFOV\n5  09:06:04.5  52:07:04 2020-01-29 11:31:07 2020-01-29 11:45:42 0.010 JFOV\n6  11:13:44.4  53:09:28 2020-01-29 13:20:41 2020-01-29 13:48:54 0.006 JFOV\n7  09:59:12.0  53:29:36 2020-01-29 13:20:41 2020-01-29 13:48:53 0.011 JFOV\n8  11:02:15.3  52:27:35 2020-01-29 13:59:08 2020-01-29 14:29:24 0.007 JFOV\n9  13:30:27.8  02:35:47 2020-01-29 18:03:07 2020-01-29 18:31:15 0.012 JFOV\n10 14:14:55.2  02:19:21 2020-01-29 18:03:07 2020-01-29 18:31:16 0.016 JFOV\n11 13:29:46.0  14:38:49 2020-01-29 18:10:38 2020-01-29 18:31:15 0.007 JFOV\n12 14:43:27.3 -14:26:44 2020-01-29 19:41:57 2020-01-29 21:15:50 0.039 JFOV\n13 14:42:23.5 -2:16:58  2020-01-29 19:51:29 2020-01-29 21:15:59 0.006 JFOV\n14 01:16:21.5 -15:28:16 2020-01-29 11:55:59 2020-01-29 12:18:06 0.003 JFOV\n15 02:08:49.9 -15:25:18 2020-01-29 11:55:59 2020-01-29 12:18:55 0.006 JFOV\n16 02:42:44.0  02:33:55 2020-01-29 10:29:21 2020-01-29 10:50:23 0.032 JFOV\n17 02:41:52.7  14:37:03 2020-01-29 10:29:46 2020-01-29 10:50:23 0.033 JFOV\n18 03:27:08.5  02:20:08 2020-01-29 10:37:52 2020-01-29 10:50:24 0.004 JFOV\n19 03:28:18.0  18:21:27 2020-01-29 10:51:19 2020-01-29 11:19:23 0.058 JFOV\n20 02:36:11.9  18:14:12 2020-01-29 10:52:39 2020-01-29 11:19:23 0.015 JFOV\n21 04:10:49.1  36:06:55 2020-01-29 11:56:45 2020-01-29 12:10:03 0.082 JFOV\n22 04:02:39.9  31:31:29 2020-01-29 11:38:13 2020-01-29 11:50:46 0.079 JFOV\n23 04:26:07.4  35:11:34 2020-01-29 10:20:42 2020-01-29 10:49:06 0.073 JFOV\n24 05:27:37.7  35:23:43 2020-01-29 10:23:32 2020-01-29 10:42:37 0.004 JFOV\n\nThe sky coverage map is available at:\nhttp://cmm.svom.cn/gwpub/O3/S200128d/S200128d.png\n(user:svomo3 pwd:gwo3).\n\nWeather conditions were clear during the observations. An average 3-sigma\nlimiting magnitude of 16 mag in the R band was obtained in the single\nframes. No credible new source was 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": 26948,
  "createdOn": 1580463895000,
  "email": "hxh@nao.cas.cn",
  "subject": "LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations",
  "submitter": "Xuhui Han at NAOC/SVOM  <hxh@nao.cas.cn>",
  "eventId": "LIGO/Virgo S200128d"
}