TITLE:   GCN CIRCULAR
NUMBER:  17706
SUBJECT: GRB 150413A : Virtual Telescope optical observations
DATE:    15/04/15 10:22:35 GMT
FROM:    Gianluca Masi at Bellatrix Astronomical Obs  <gianluca@bellatrixobservatory.org>

G. Masi and P. L. Catalano, the Virtual Telescope Project - Italy, report:

We started time-series observations of GRB 150413A (C. B. Markwardt et al., GCN 
17688) with the 17" robotic unit part of the Virtual Telescope (Ceccano, Italy) 
at 21:25:00 UT, that is 7.5 hours after the burst.

An optical source is visible where described by K.Ivanov et al. (GCN 117689) on 
60s and 120s exposures, unfiltered. The position of the source is RA: 12 41 
41.97 Decl.: +71 50 27.7 (J2000.0, mean residuals of 0.2") and the magnitude was 
estimated to be 18.0, assuming R mags for the reference stars from UCAC-4.

We covered the source for about one hour, detecting a fadind of about 0.4 mags 
from the start to the end of the series.

Details are available on the page:
http://goo.gl/8jCkhs

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