GCN Circular 36264
Subject
LIGO/Virgo/KAGRA S240422ed: LAST optical observations
Date
2024-04-23T20:12:14Z (15 days ago)
From
Simone Garrappa at DESY <simone.garrappa@desy.de>
Via
email
R. Konno (WIS), S. Garrappa (WIS), E. O. Ofek (WIS), S. Ben-Ami (WIS), David Polishook (WIS) on behalf of the LAST collaboration:
We report observations of the Bilby.fits skymap of the NSBH merger event S240422ed (GCN 36236) with the Large Array Survey Telescope (LAST; Ofek et al. 2023 PASP 135, 5001; Ben-Ami et al. 2023 PAST 135, 5002).
We used 8 telescopes (out of 32 operational) with no filter (clear - similar to the GAIA Bp band) to cover 70% of the 90% confidence region of the event. A total of 11 fields were observed, each for a total of 40x20 seconds integration.
The fields were observed at an airmass of about 2.0, with the full Moon at about 78 deg distance. Under these conditions, the limiting magnitude reported by the LAST pipeline (Ofek et al. 2023 PASP 135, 4502) in 20x20 s exposures is about 18.5.
No reference images are available for these fields.