GCN Circular 29320
Subject
GRB 200613A: Host galaxy redshift from OSIRIS/GTC
Event
Date
2021-01-18T17:29:38Z (5 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D.A. Kann (HETH/IAA-CSIC),
C.C. Thoene (HETH), M. Blazek, and J. F. Agui Fernandez (both HETH/IAA-CSIC)
report:
We obtained spectroscopy of the host galaxy of GRB 200613A (Fermi-LAT
detection: Ohno et al. GCN #27931; Fermi GBM detection: Bissaldi & Lesage,
GCN #27930; optical counterpart discovery: Kann et al. GCN #27935) with OSIRIS,
mounted on the 10.4m GTC telescope (Roque de los Muchachos Observatory,
La Palma, Spain). The observation was performed on the 18 January 2021 with
mean epoch at 00:02 UT (218.75 days after the burst) and consisted of 3x1200s
exposures with grism R1000R, covering the range between 5100 and 10100 ��.
The spectrum is characterised by a continuum that is detected over the complete
spectral range, with better SNR in the blue part of the spectrum, and has a strong
emission feature that we identify as the [OII] 3727/3729 doublet, at a redshift of
1.2280. At a similar redshift of 1.2255 we also identify absorptions due to FeII and
MgII, that allow us to confirm the redshift, which we identify as that of GRB 200613A.