{
  "bibcode": "2019GCN.25639....1B",
  "body": "Kevin Burdge (Caltech), Daniel A. Perley (LJMU) and Mansi M. Kasliwal\n(Caltech) report on behalf of the GROWTH collaboration:\n\nWe obtained a Keck I LRIS spectrum of ZTF19abvizsw (Kool et al. GCN\n25616).  The reduced spectrum shows a featureless continuum superimposed\nwith a number of narrow absorption lines, including Mg II, Mg I, and Fe II\nat a consistent redshift of z=1.26.\n\nThis is far beyond the GW distance constraints on S190901ap (LVC et al. GCN\n25614, GCN 25606) and demonstrates that this source is unrelated to the\nLIGO/Virgo source.  It could be a flaring AGN or blazar, but there is no\ncounterpart in PS1 or WISE and only a dim, marginal object at this location\nin the Legacy Survey.  It may also be a GRB afterglow.\n\nOur conclusions disagree with those of Salmaso et al. (GCN 25618), who\nreported an M- or K-dwarf spectrum for this object.  We note that there is\na bright, red star less than 2 arcsec away from the transient position and\nit is possible that the spectrum reported in GCN 25618 may correspond to\nthat object.",
  "circularId": 25639,
  "createdOn": 1567556835000,
  "email": "mansikasliwal@gmail.com",
  "subject": "LIGO/Virgo S190901ap: Keck I LRIS spectroscopy of ZTF19abvizsw",
  "submitter": "Mansi M. Kasliwal at Caltech/Carnegie  <mansikasliwal@gmail.com>",
  "eventId": "LIGO/Virgo S190901ap"
}