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GCN Circular 34939

GRB231104A: LCOGT Optical Upper Limits
2023-11-04T04:09:15Z (8 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 Fermi GRB 231104A field (Fermi GBM team, GCN 34937) with the LCOGT 1-meter Sinistro instrument at the McDonald Observatory, USA site, on November 4, from 02:53 to 03:25 UT (corresponding to 1.10 to 1.63 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 candidate X-ray source (Page et al., GCN 34938) in either band.

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

r > 22.6
i > 21.8

These magnitudes are not corrected for galactic extinction.

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