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GCN Circular 35278

GRB 231205B: LCOGT Optical Upper Limits
2023-12-06T04:03:52Z (6 months ago)
Robert Strausbaugh at Eastern Illinois University <>
R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:

We observed the Swift GRB 231205B field (Evans et al., GCN 35269) with the LCOGT 1-meter Sinistro instrument at the McDonald Observatory, USA site, on December 6, from 01:40 to 02:12 UT (corresponding to 8.95 to 9.48 hours from the GRB trigger time) with the SDSS r and i filters.

We performed a series of 3x300s exposures in each band.  We do not detect a source within the Swift-XRT error region around the enhanced XRT position (Osborne et al., GCN 35275) in either band, consistent with other non-detections (Odeh et al., GCN 35270)

The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference:

r > 22.6
i > 21.9

These magnitudes are not corrected for galactic extinction.

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