TITLE:   GCN CIRCULAR
NUMBER:  40759
SUBJECT: GRB 250615A: Calapai Observatory, Massa S. Giorgio (Messina), upper limit
DATE:    25/06/17 16:55:47 GMT
FROM:    Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, Messina, Italy <giovannicalapai@tiscali.it>

Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, (Messina) Italy 
Member of: GRB/UAI Gamma Ray Burst Section of Unione Astrofili Italiani. 

Report:

We imaged the field of GRB 250615A detected by Swift/BAT (Dichiara et al. GCN 40736), with the 11 inches Schmidt-Cassegrain (Celestron 11) telescope F/D=6,3. 

The observations were started at 2025-06-15 23:21:59 UT (approximately 56 minutes after burst) stacking a set of unfiltered CCD image.

We co-added 180 exposures of 60 sec each.

Start T0+      End T0+     CR lim
0.94 hour     4.33 hour     19.6

We did not found any optical uncatalogued object within the Swift error circle.

Magnitudes were estimated with the PanSTARRS cat. and are not corrected for galactic dust extinction.

Our upper limit is consistent with other observations reported by Kuin et al. (GCN 40747), Becerra et al. (GCN 40748), Magnani et al. (GCN 40749).

The message may be cited.