{
  "bibcode": "2022GCN.31884....1B",
  "body": "S. Beradze (AbAO), U. Bhardwaj (GRAPPA), T. Culino (ESILV), P. Hello\n(IJCLAB), M. Masek (FZU), G. Raaijmakers (GRAPPA), Y. Rajabov (UBAI),\nT. Sadibekova (AIM/CEA-UPS), F. Z. Guo (THU), X. F. Wang (THU/BJP), Y.\nZhu (NAOC), J. Zhang (NAOC), D. A. Kann (HETH/IAA-CSIC), K. Noysena\n(TRT-SRO), C. Rinner (OUCA), Z. Benkhaldoun (OUCA), J. Zhu (BJP),\nX. Song (BJP), S. Antier (OCA/Artemis), P. A. Duverne (IJCLAB), A. Simon\n(Kyiv Univ), A. Baransky (Kyiv Univ) and V. Godunova (IC ICAMER)\nreport on behalf of GRANDMA collaboration:\n\nThe GRANDMA telescope network responded to the alert of GRB 220408A\n(Caputo et al. GCNC 31848). The first observations started 0.63 h after\nthe SWIFT BAT trigger time.\n\nWe did not detect the optical afterglow within the first 24 h.\nUpper limits are given in the AB system, at 3-sigma.\n\n\nT-T0(hr)| MJD������ | Observatory�� | Exposure| Filter | Upp. Lim. (AB)\n___________________________________________________________________________\n0.63 |59677.26659|KNC-T19������������ |9*300 s�� |�� V ������ ���� |���� 17.7\n1.82 |59677.31602|SRO�������������������� |7*60 s���� |�� R ������ ���� |���� 19.8\n6.27 |59677.50176|Xinglong-2.16m|9*400 s�� |�� Rc������ ���� |���� 20.3\n8.45 |59677.59259|BJP/ALi-50������ |21*20 s�� |�� Clear |���� 21.4\n14.89|59677.86076|MOSS������������������ |45*60 s�� |�� Clear |���� 20.3\n18.76|59678.02215|KNC-HAO������������ |23*180 s |�� Lumen |���� 20.6\n\nThese upper limits are consistent with previous reports of detections by\nUVOT (Caputo et al. GCNC 31848, Oates et al. GCNC 31855), KAIT (Zheng et al.\nGCNC 31850), LCO (R. Strausbaugh et al. GCNC 31862), NOT (Zhu et al. GCNC\n31864), RATIR (Watson et al. GCNC 31870), and LDT (B. O'Connor et al. GCNC\n31875), and the upper limits provided by MASTER (Lipunov et al. GCNC 31849),\nXinglong-2.16m (Jiang et al. GCNC 31853), GIT (Kumar et al. GCNC 31857),\nLOAO/SAO/DOAO (Paek et al. GCNC 31867), and 1.3m DFOT (Kumar et al. GCNC\n31868).\n\nThe SRO, Xinglong-2.16m, and Ali-50 data have been calibrated with four \nstars\nfrom the Pan-STARRS catalog, using the transformations by Lupton (2005) and\nusing Rc values for the Clear Al-50 observation. The MOSSm KNC-T19 and\nKNC-HAO images have been calibrated using field stars from the \nPanSTARRS-DR1\ncatalog, measured with the MUPHOTEN pipeline (Duverne et al. 2021).\n\nGRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr)\ndevoted to the observation of transients in the context of multi-messenger\nastrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is\nthe citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/).",
  "circularId": 31884,
  "createdOn": 1649776813000,
  "email": "sarah.antier@oca.eu",
  "subject": "GRB 220408A: GRANDMA observations",
  "submitter": "Sarah Antier at OCA  <sarah.antier@oca.eu>",
  "eventId": "GRB 220408A"
}