TITLE:   GCN CIRCULAR
NUMBER:  33992
SUBJECT: GRB230618A: LCOGT Optical Observations
DATE:    23/06/18 06:19:09 GMT
FROM:    Robert Strausbaugh at University of Minnesota <rstrausb@umn.edu>

R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on
behalf of a larger collaboration:

We observed the GRB 230618A (Page et al., GCN 33989) field with the LCOGT
1-meter Sinistro instrument at the McDonald Observatory, Texas, USA site,
on June 18, from 04:31 to 05:03 UT (corresponding to 0.33 to 1.20 hours
from the GRB trigger time) with the SDSS r and i filters.

We performed a series of 3x300s exposures in each band.  We detect an
uncatalouged source within the Swift-XRT enhanced error region (P.A. Evans
et al., GCN 33990).

The following magnitudes are calculated using the PanSTARRS catalog as
reference:

r = 20.62 +/- 0.02
i = 19.16 +/- 0.02

These magnitudes are not corrected for galactic extinction.