{
  "bibcode": "2015GCN.17696....1P",
  "body": "D. A. Perley (Caltech) and S. B. Cenko (GSFC) report:\n\nThe Palomar 60-inch telescope observed the location of the optical \ncounterpart of GRB 150413A (Markwardt et al., GCN 17688; Ivanov et al., \nGCN 17689) starting at 03:15:21 UT on 2015-04-14.  We acquired 3x180s \nimages in griz filters under good conditions.\n\nThe optical transient is well-detected in all four filters.  Calibrating \nrelative to USNO stars in the field, we measure a magnitude of R = 19.1 \n(+/- 0.1) mag at this time (t = 0.560 days after the BAT trigger), \nindicating significant fading since the early observations.\n\nFurther follow-up is planned.",
  "circularId": 17696,
  "createdOn": 1428986461000,
  "email": "dperley@astro.caltech.edu",
  "subject": "GRB 150413A: P60 photometry",
  "submitter": "Daniel Perley at Caltech  <dperley@astro.caltech.edu>",
  "eventId": "GRB 150413A"
}