{
  "bibcode": "2013GCN.15153....1I",
  "body": "L. Izzo and L. D'Avino report:\n\nWe have observed the optical afterglow of GRB 130831A using a 0.32m =\nf/9.3 Ritchey-Chretien telescope of the iTelescope network, at Siding =\nSpring =96 Australia.\n\nWe have detected the afterglow in the R and V, but not in the B band. =\nAfter an ensemble photometry, using nearby SDSS stars, and correction =\nfrom SDSS to V and R filters, we have obtained  the following =\nmagnitudes:\n\nR =3D 15.58 +- 0.09  (78 min post-trigger =96 240s exposure)\n\nV =3D 16.89 +- 0.09  (92 min post-trigger =96 180 s exposure)\n\nThe R-composite image can be seen at\nhttp://blacksabburst.files.wordpress.com/2013/08/r_median.png",
  "circularId": 15153,
  "createdOn": 1378000579000,
  "email": "Luca.Izzo@ICRA.it",
  "subject": "GRB 130831A: optical observations",
  "submitter": "Luca Izzo at ICRA  <Luca.Izzo@ICRA.it>",
  "eventId": "GRB 130831A"
}