{
  "bibcode": "2021GCN.30274....1B",
  "body": "M. Blazek, D. A. Kann (both HETH/IAA-CSIC), A. de Ugarte-Postigo (HETH/IAA-CSIC,\nDARK/NBI), C. Thoene and J.F. Agui Fernandez (both HETH/IAA-CSIC) report:\n\nWe observed the afterglow of GRB 210619B (Swift detection: D'Avanzo et al., GCN\n30261; GECAM detection: Zhao et al., GCN 30264; Fermi-LAT detection: Axelsson et\nal., GCN 30270; Afterglow detections: Lipunov et al., GCN 30259; D'Avanzo et\nal., GCN 30261; Lipunov et al., GCN 30262; Jelinek et al., GCN 30263; Kong, GCN\n30265; Pellegrin et al., GCN 30268; Perley, GCN 30271; Zheng & Filippenko, GCN\n30273; Redshift: de Ugarte Postigo, GCN 30272) with the 2-m Liverpool Telescope\nlocated in La Palma, Spain using IO:O camera. The observation started at\n02:57:49 UT on June 20, 2021 (t-t0 = 2.97 hours). We obtained 60x45 seconds\nexposures in r'. The afterglow is clearly detected in each image. Comparing\nto 33 check stars from the PanSTARRS catalogue we derived the decay starting with\n\nr' = 17.91 +- 0.01 mag\n\nand ending at 03:45:43 UT (t-t0 = 3.77) hours with\n\nr' = 18.10 +- 0.02 mag\n\nMagnitudes are given in AB photometric system. These values have not been\ncorrected for Galactic extintion.",
  "circularId": 30274,
  "createdOn": 1624203461000,
  "email": "alf@iaa.es",
  "subject": "GRB 210619B: Liverpool Telescope r'-band observations",
  "submitter": "Martin Blazek at HETH/IAA-CSIC  <alf@iaa.es>",
  "eventId": "GRB 210619B"
}