{
  "bibcode": "2020GCN.27348....1K",
  "body": "D. A. Kann (HETH/IAA-CSIC), A. de Ugarte Postigo (HETH/IAA-CSIC, \nDARK/NBI), M. Blazek, C. C. Thoene, J. F. Agui Fernandez (all \nHETH/IAA-CSIC), R. Pedro Hedrosa, and E. Gallego (both CAHA) report:\n\nWe observed the field of the afterglow of GRB 200306C (Lipunov et al., \nGCNs #27324, #27325; Gropp et al., GCN #27326; Jelinek et al., GCN \n#27328; Hu et al., GCN #27329; Moskvitin, GCN #27333; Izzo &\nPerley, GCN #27334; Kann et al., GCN #27335; Steele et al., GCN #27338) \nwith the 2.2m telescope of Calar Alto equipped with CAFOS. We obtained 4 \nx 720 s images in the Rc band under adverse conditions (moonlight, \npassing clouds, bright star still there).\n\nOur stacked image centred at mean epoch 1.25519 d after the GRB shows no \ndetection to a 3-sigma upper limit of Rc > 23.0 mag (AB). The magnitude \nlimit was obtained versus SDSS stars in the field.",
  "circularId": 27348,
  "createdOn": 1583653425000,
  "email": "kann@iaa.es",
  "subject": "GRB 200306C: Calar Alto 2.2m upper limit",
  "submitter": "Alexander Kann at IAA-CSIC  <kann@iaa.es>",
  "eventId": "GRB 200306C"
}