TITLE:   GCN CIRCULAR
NUMBER:  34259
SUBJECT: GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
DATE:    23/07/25 21:01:33 GMT
FROM:    Claudio Lopresti <cl3lop@gmail.com>

Claudio Lopresti (Gruppo Astronomia Digitale - GAD Observatory, La Spezia, Italy)
in a large collaboration with:
M.G. Dainotti (National Astronomical Observatory of Japan), 
Y. Niino (Tokyo University, Institute of Astronomy), 
K. Kalinowski (Aarhus University, Department of Physics and Astronomy),
B. De Simone (Universita' degli Studi Di Salerno)
Unione Astrofili Italiani (UAI)
report: 
 
We imaged the field of GRB 230723B detected by SWIFT(trigger 1180410)
with the telescope LX200 12” of GAD Observatory, La Spezia, Italy
Member of: 
 
UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.
GAD - Gruppo Astronomia Digitale.
 
The observations started 557 min after the GRB trigger, at the end of twilight, 
with a Shmidt-Cassegrain telescope D=304 mm with reducer F/D=4.75.
 
Weather conditions were medium.
 
We co-added 42 exposures of 120 sec each.
 
 
Start T0+      End T0+       R lim
557 min        641 min         19
 
We did not found any optical counterpart in the error box of the XRT candidate.
Page et al. GCN 34234
 
Magnitudes were estimated with the Gaia EDR3 cat. and 
are not corrected for galactic dust extinction.
 
Reference:
https://www.parcodellestelle.com/
 
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