{
  "bibcode": "2021GCN.31229....1D",
  "body": "A. de Ugarte Postigo (Obs. Cote d���Azur), D.A. Kann, C. Thoene, \nJ.F. Agui Fernandez, M. Blazek (HETH/IAA-CSIC), I. Vico and \nA. Guijarro (CAHA) report: \n\nWe obtained further i-band imaging of the afterglow of GRB 211211A \n(Fermi team GCN31201; D���Ai et al. GCN31202; Zheng and Filipenko \nGCN 31203) from CAFOS/2.2m CAHA 2.66 days after the burst onset.\n\nThe observation consisted of 20x120s exposures under good seeing \nand yielded a faint detection. The light curve decay, compared to our \nprevious observation from Calar Alto (de Ugarte Postigo et al., GCN \n31228) indicates an extreme decay index of alpha = 3.25+/-0.40. \nThis is similar to what is observed from the XRT light curve, which \ncurrently decays with an index of 3.2 (-0.7,+0.8) \n(https://www.swift.ac.uk/xrt_live_cat/01088940/ <https://www.swift.ac.uk/xrt_live_cat/01088940/>; Evans et al. 2007; \nEvans et al. 2009). We note that this is amongst the fastest post-break\ndecays that are normally observed for GRB afterglows.\n\nFurther observations with larger telescopes are encouraged.",
  "circularId": 31229,
  "createdOn": 1639499145000,
  "email": "deugarte@iaa.es",
  "subject": "GRB 211211A: Very fast decay observed from CAFOS/2.2mCAHA",
  "submitter": "Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>",
  "eventId": "GRB 211211A"
}