GCN Circular 33334
Subject
GRB 230205A: Lowell Discovery Telescope Observations
Date
2023-02-17T00:43:14Z (a year ago)
From
Brendan O'Connor at UMD <oconnorb@umd.edu>
B. O'Connor (UMD, GWU), E. Hammerstein (UMD), S.B. Cenko (UMD,
NASA-GSFC), E. Troja (UTV, ASU), S.Dichiara (PSU),
J. Durbak (UMD, NASA-GSFC), A. Kutyrev (UMD, NASA-GSFC),
S. Veilleux (UMD), I. Andreoni (UMD, NASA-GSFC), and
G. Srinivasaragavan (UMD):
We observed the field of GRB 230205A (Ambrosi et al. GCN 33271;
Sakamoto et al. GCN 33280) using the Large Monolithic Imager (LMI)
on the 4.3m Lowell Discovery Telescope (LDT) at Happy Jack, AZ.
We began observations on February 13, 2023 at 12:54:52 UT in
r-band and i-band for 600 s each. The target was at airmass
1.1 with seeing ~2".
We do not detect any source within the XRT enhanced position
(Goad et al. GCN 33275) to depth r>23.8 AB mag. The host
galaxy candidate (Tomasella et al. GCN 33302), hereafter S1,
is clearly detected in both filters. We likewise detect
the source (S2) reported by Urata et al. (GCN 33307).
We measure the following magnitudes for S1 and S2:
S1: r ~ 22.0 +/- 0.1 AB mag
S1: i ~ 21.20 +/- 0.05 AB mag
S2: r ~ 23.7 +/- 0.3 AB mag
S2: i ~ 22.7 +/- 0.2 AB mag
The magnitudes of S1 are consistent with the earlier report
of Tomasella et al. (GCN 33302) and the SDSS catalog. For S2,
we derive a slightly fainter i-band magnitude compared to
Urata et al. (GCN 33307). However, as their images were obtained
prior to the explosion, this is not an indication of fading.
Thus, both these sources are candidate host galaxies to
GRB 230205A (Schroeder et al. GCN 33309).
Magnitudes are calibrated against the SDSS catalog and are not
corrected for Galactic extinction.
We thank the staff of the Lowell Discovery Telescope for assistance
with these observations.