GCN Circular 34436

Giulio Scarfì  (Iota Scorpii Observatory, La Spezia,Italy)
mail terziaria@gmail.com

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)

Members of:

GAD - Gruppo Astronomia Digitale.
AAVSO - American Association of Variable Star Observers.
UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili-GRB.

report:

I have observed the field of GRB 230812B (Lesage et al., GCN 34387
Not found
 
 
;
Scotton et al., GCN 34392
Not found
 
 
; Page, GCN 34394
Not found
 
 
; Zheng & Filippenko, GCN
34395
Not found
 
 
; Lipunov et al., GCN 34396
Not found
 
 
; Salgundi et al., GCN 34397
Not found
 
 
; Ackley
et al., GCN 34398
Not found
 
 
; Xiong et al., GCN 34401
Not found
 
 
; Casentini et al., GCN
34002
Not found
 
 
; Frederiks et al., GCN 34403
Not found
 
 
; Mao et al., GCN 34404
Not found
 
 
; Odeh et
al., GCN 34405
Not found
 
 
; Moskvitin & Spiridonova GCN 34406
Not found
 
 
; Leonini et al. GCN
34408
Not found
 
 
; de Ugarte Postigo et al. GCN 34409
Not found
 
 
; de Ugarte Postigo et al.
GCN 34410
Not found
 
 
; Belkin et al. GCN 34412
Not found
 
 
; Ruocco et al. GCN 34413
Not found
 
 
; Frederiks
et al. GCN 34414
Not found
 
 
; Ruocco et al. GCN 34415
Not found
 
 
; Shrestha et al. GCN 34416
Not found
 
 
;
Quadri et al. GCN 34417
Not found
 
 
; Adami et al. GCN 34418
Not found
 
 
; Moretti et al. GCN
34419
Not found
 
 
; Kumar et al. GCN 34420
Not found
 
 
; Belkin et al. GCN 34421
Not found
 
 
 & GCN 34423
Not found
 
 
;
Pyshna et al., GCN 34425
Not found
 
 
) with my 0.40-m Ritchey-Cretien telescope.

The observations started 1660 min after the GRB trigger, at the end of
twilight,
with a Ritchey Cretien D=406 mm with reducer F/D=6,15.
Weather conditions were good.


Add 12 x 300 sec. unfiltered images on August 13 2023,
from 20:26:35 to 21:21:42 UT


Start T0+      End T0+       R lim
1660 min        1735 min         20


I confirm a fading afterglow


The results of photometry are:


      JD         mag      Err   Flt

2460170.36555307   19.85  +/- 0.2   CLEAR


Magnitudes were estimated with the Atlas catalog and
are not corrected for galactic dust extinction.



Reference:
http://www.iotascorpiiobservatory.it



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