TITLE:   GCN CIRCULAR
NUMBER:  34254
SUBJECT: GRB 230723B: Leavitt Observatory upper limit
DATE:    23/07/24 20:32:05 GMT
FROM:    leavittob@gmail.com

E. Pavoni and L. Moretti (Leavitt Observatory), 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)
report: 

We imaged the field of GRB 230723B detected by SWIFT(trigger 1180410)
with telescope of Leavitt Observatory, Italy. Member of: 
UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.
ATA - Associazione Tuscolana di Astronomia.

The observations began at 21:31 UT on 2023/07/23, 577 min after the GRB trigger, with our RC telescope D=250 mm F/D=8.

Weather conditions were medium.

We took 30 images of 120 sec each. All images are unfiltered, calibrated with master dark and master flat, stacked with ASTAP software.

We have not detected any clearly visible sources, up to 19.9th magnitude with clear sky at 
RA(J2000)  = 16h 41m 43.83s
Dec(J2000) = -05d 17' 16.04"

on a field of view 31.1 x 26.8 arcmin

Start                End              Rlim
577 min         637 min      19.9

Magnitudes were estimated with the Gaia DR3 cat. and are not corrected for galactic dust extinction.

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