TITLE:   GCN CIRCULAR
NUMBER:  21273
SUBJECT: GRB 170626A: OASDG optical observations
DATE:    17/06/27 14:15:22 GMT
FROM:    Luca Izzo at IAA-CSIC  <Luca.Izzo@ICRA.it>

L. Izzo (IAA-CSIC), L. D'Avino, A. Noschese, M. Mollica, L. Morrone, N. Ruocco, A. Vecchione (AC-OASDG) report:

We observed the field of GRB 170626A (Marshall et al. GCN 21264) with the 0.5m telescope of the Osservatorio Astronomico S. Di Giacomo located in Agerola, Italy ( http://acgo.it/oa ).  
We obtained a series of 18x180 s images in the Rc filter, starting at 20:48:16 UT, ~ 11.2 hrs after the GRB trigger. We detect the GRB afterglow (Moskvitin GCN 21268, de Ugarte Postigo et al. GCN 21269, Melandri et al. GCN 21270, Lipunov et al. GCN 21272) and measure a magnitude of R(AB) = 20.1 +- 0.5. 

An image of the field can be seen at http://acgo.it/grb26a