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GCN Circular 34961

GRB 231104A: FRAM-ORM optical limit
2023-11-07T13:35:15Z (6 months ago)
Martin Jelinek at Astro.Inst-AVCR,Ondrejov <>
legacy email
Alzbeta Malenakova, Martin Jelinek and Jan Strobl (ASU CAS Ondrejov, CZ),
Sergey Karpov, Martin Masek, Petr Janecek, Jakub Jurysek,
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)


The 25cm robotic telescope FRAM-ORM at La Palma (Spain) reacted robotically
to the Fermi-GBM/Swift/Fermi-LAT/AstroSat CZTI alert of GRB 231104A (Bala
et al., GCNC 34937, Page et al., GCNC 34938 and Goad et al., GCNC 34940,
Principe. et al. 2023, GCNC 34943, Navaneeth et al., GCNC 34945), obtaining
a series of 20s unfiltered images starting at 01:48:10.3 UT, i.e. 31.3s
post trigger, covering the third gamma ray episode of the GRB.

We do not detect any new source in comparison to Atlas Refcat 2.0 (Tonry et
al., 2018) neither in single images (detection limit r'>17.6) nor in a
combined 40x20s frame (mean exp time 960s post trigger, with a limit
r'>18.6) similarly to Strausbaugh et al. (GCNC 34939), Kuin et al. (GCNC
34941), Odeh et al. (GCNC 34946), Zhu et al. (GCNC 34951), Gupta et al.
(GCNC 34955) and Busman et al. (GCNC 34958).

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