{
  "bibcode": "2015GCN.17744....1P",
  "body": "D. A. Perley (Caltech) reports:\n\nFurther to GCN 17733, I report analysis of the spectroscopy acquired of \n  S2, the neighboring object located 4.0 arcseconds northeast of the \noptical afterglow of GRB 150423A, first announced by Varela et al. (GCN \n17732).\n\nThe spectrum of this object shows weak emission lines from OII (3727), \nOIII (5007), Halpha (6563), and marginally Hbeta (4861), all at a common \nredshift of z=0.456.  No features are visible in the trace of S1 at any \nof the same wavelengths (or elsewhere in its spectrum).\n\nAt this redshift, the offset between the sources corresponds to 23 kpc \nin projection.\n\nFurther observations of S1 will be necessary to determine whether it is \nentirely afterglow or if it also contains flux from a (coincident) host \ngalaxy, perhaps at a different redshift.",
  "circularId": 17744,
  "createdOn": 1429866925000,
  "email": "dperley@astro.caltech.edu",
  "subject": "GRB 150423A: Keck redshift of neighboring galaxy",
  "submitter": "Daniel Perley at Caltech  <dperley@astro.caltech.edu>",
  "eventId": "GRB 150423A"
}