{
  "bibcode": "2021GCN.30294....1Z",
  "body": "Z.P. Zhu (NAOC, HUST), A. de Ugarte Postigo (HETH, IAA-CSIC), D. B. \nMalesani (DTU Space), L. Izzo (DARK/NBI), D. Alexander Kann (HETH, \nIAA-CSIC), D. Xu (NAOC), A. Amanda Djupvik (NOT) report on behalf of a \nlarger collaboration:\n\nWe observed GRB 210619B detected by Swift/BAT (D'Avanzo et al., GCN \n30261) with the Nordic Optical Telescope (NOT) equipped with StanCAM. \nObservations started at 04:16:27 UT on 2021-06-21, and we obtained 3x300 \ns exposures in the Bessel R filter, 5x200 s in the SDSS z-filter, and \n3x300 s in the i-filter (similar to SDSS i).\n\nThe previously reported optical afterglow (e.g., Lipunov et al. GCN \n30259; Zhao et al. GCN 30261; Jelinek et al. GCN 30263; Kong et al. GCN \n30265; Axelsson et al. GCN 30270; Perley et al. GCN 30271; de Ugarte \nPostigo et al. GCN 30272; Zheng et al. GCN 30273; Blazek et al. GCN \n30274; Kann et al. GCN 30275; Svinkin et al. GCN 30276; Xin et al. GCN \n30277; Shrestha et al. GCN 30280; Jelinek et al. GCN 30281; Kumar et \nal., GCN 30286; D'Avanzo et al., GCN 30288; D'Avanzo et al., GCN 30289; \nMoskvitin et al., GCN 30291; GCN 30292) is clearly detected in our \nimages. Preliminary photometric results are as follows:\n\nT_mid/d  Filter\t Mag\t   MagErr\tMagSysten\n1.18338\tR\t19.92      0.02\t    Vega\n1.21390\ti\t19.65      0.02\t     AB\n1.20022\tz\t18.88      0.11\t     AB\n\ncalibrated by the PS1 catalogue.",
  "circularId": 30294,
  "createdOn": 1624293697000,
  "email": "dxu@nao.cas.cn",
  "subject": "GRB 210619B: NOT optical observations",
  "submitter": "Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>",
  "eventId": "GRB 210619B"
}