GCN Circular 37150

U.Quadri, L.Strabla and P.Madurini (Bassano Bresciano Astronomical Observatory - Italy),

Members of:
AAVSO - American Association of Variable Star Observers.
UAI/SSV - Unione Astrofili Italiani/SSV-GRB section.
GAC - Gruppo Astrofili Cremonesi.

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 240811A detected by SWIFT(trigger 1248132) with the robotic telescope of (IAU station 565) Bassano Bresciano Observatory, Italy.
The observations started 5.56 hour after the GRB trigger, At the end of twilight with our Newton telescope D=450 mm F/D=4.5.

Weather conditions were good.

We co-added 150 exposures of 20 sec each (total 50 min).

Start T0+      End T0+      Vlim
5.56 hour     6.47 hour      21

We did not found any optical counterpart in the error box of the XRTcandidate (K. L. Page & R. Gupta, GCN 37136
Not found
 
 
; v. Lipunov et al., GCN 37137
Not found
 
 
; Guowang Du et al., GCN 37140
Not found
 
 
; A.P. Beardmore et al., GCN 37141
Not found
 
 
; R. Strausbaugh and A. Cucchiara, GCN 37142
Not found
 
 
; N. P. M. Kuin and K. L. Page, GCN 37147
Not found
 
 
; T. Sbarrato et al., GCN 37149
Not found
 
 
).

Magnitudes were estimated with the pan-STARRS cat and are derived using Lupton (2005) equations.

Not corrected for galactic dust extinction.

Reference:
http://www.osservatoriobassano.org/grb.asp

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