GCN Circular 21277
Subject
GRB 170626A: SAO RAS confirmation of OT fading
Date
2017-06-27T22:58:52Z (7 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
A. Moskvitin (SAO RAS), A. Volnova (IKI RAS), A. Pozanenko (IKI RAS),
I. Reva (Fesenkov Astrophysical Institute),
report on behalf of larger GRB follow-up team:
We observed the field of the GRB 170626A (Marshall et al., GCNC 21264)
with the 1-m telescope of SAO RAS, Zeiss-1000 on June, 27.
The OT observed by numerous telescopes (de Ugarte Postigo et al.,
GCNC 21269; Melandri et al., GCNC 21270; Gres et al. GCNC 21272;
Izzo et al., GCNC 21273; Volnova et al., GCNC 21276)
is approx. 0.9 magnitude fainer than in previous SAO epoch.
F ~ (t-T0)^ alpha. The decay slope alpha is about -0.7.
ftp://ftp.sao.ru/pub/grb/GRB170626A/GRB170626A_2epochs.png
The result of the first SAO epoch (GCNC 21268) were checked with the
full 1.5 hour stack obtained during the first night.
The stacked frames of both epochs were re-calibrated
against all standards mentioned by Volnova et al. (GCNC 21276).
The results are presented in the following table.
The errors are statistical only.
Date UT start T_mid - T0, d Filter Exp., s mag_OT Err.
2016.06.26 19:57:42 0.4695 Rc 18 x 300 19.83 +/- 0.04 (GCNC
21268)
2016.06.27 18:50:27 1.4079 Rc 12 x 300 20.68 +/- 0.07