{
  "bibcode": "2022GCN.31883....1S",
  "body": "X. Song, J. Zhu (BJP), I. Tosta e Melo (INFN-LNS), J.-G. Ducoin (IAP),\nN. Guessoum (AUS), W. Corradi (LNA), T. Culino (OCA), E. Gurbanov (ShAO),\nE. Hesenov (ShAO), A. de Ugarte Postigo, S. Antier (OCA/Artemis), L. Wang,\nA. Iskandar (XAO), X. F. Wang (TSU/BJP), X. Zeng (CTGU), D. Marchais (KNC),\nP.A. Duverne, N. Leroy (IJCLAB), D. A. Kann (HETH/IAA-CSIC), A. Simon,\nA. Baransky (Kyiv univ), V. Godunova (IC ICAMER),\nreport on behalf of GRANDMA collaboration:\n\nThe GRANDMA telescope network responded to the alert of GRB 220403B\n(Klingler et al., GCN 31820). The first observations started 8 min after\nthe BAT trigger time.\n\nWe clearly detect the afterglow within the first hour.\nWe also report our 3-sigma upper limits. Magnitudes are given in the\nAB system.\n\nT-T0 (hr)| MJD���� | Obser.���� |Exposure| Filter | Mag +/- err�� | Upp.Lim. (AB)\n___________________________________________________________________________\n0.13 |59672.86832| ALi-50���� | 5x20s�� | Clear�� | 18.4 +/- 0.1 | -\n0.35 |59672.8775 | ALi-50���� | 20x20s | SDSS g'| 19.7 +/- 0.1 | -\n0.48 |59672.88298| ALi-50���� | 20x20s | SDSS r'| 18.6 +/- 0.1 | -\n17.67|59673.59939| SNOVA������ | 15x300s| Clear�� |������������ -���������� | 19.4\n24.72|59673.89285| KNC-T-CAT| 240x32s| Blue���� |������������ -���������� | 20.9\n24.72|59673.89285| KNC-T-CAT| 240x32s| Green�� |������������ -���������� | 20.9\n24.72|59673.89285| KNC-T-CAT| 240x32s| Red������ |������������ -���������� | 19.9\n\nThese detections and limits are consistent with the detections and limits\npreviously reported in Klingler et al. (GCN 31820), Jelinek et al.\n(GCN 31821),Nicuesa Guelbenzu et al. (GCN 31822), Zhu et al. (GCN 31823),\nLipunov et al. (GCN 31825),�� Rossi et al. (GCN, 31826), Grossan et al.\n(GCN 31830), Pankov et al. (GCN 31837, 31844), Hu et al. (GCN 31841),\nand Kumar et al. (GCN 31869).\n\nThe photometry of Ali-50 was performed using field stars from the\nPanSTARRs-DR1 catalog for images with SDSS g' and r' filters, and from the\nGaia gmag catalog for images with no filters. The SNOVA and T-CAT data have\nbeen processed using field stars from the PanSTARRS-DR1 catalog and with \nthe\nMUPHOTEN 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": 31883,
  "createdOn": 1649751689000,
  "email": "sarah.antier@oca.eu",
  "subject": "GRB 220403B: GRANDMA observations",
  "submitter": "Sarah Antier at OCA  <sarah.antier@oca.eu>",
  "eventId": "GRB 220403B"
}