GCN Circular 20981

Zsolt Paragi (JIVE)
Tao An (Shanghai Astronomical Observatory)
Philippe Bacon (APC Universite�� Paris Diderot)
Rob Beswick (JBO-Manchester University)
Eric Chassande-Mottin (APC Universite�� Paris Diderot)
Sa��ndor Frey (Konkoly Observatory)
Marcello Giroletti (IRA-INAF)
Peter Jonker (SRON)
Mark Kettenis (JIVE)
Benito Marcote (JIVE)
Arpad Szomoru (JIVE)
Huib van Langevelde (JIVE)
Jun Yang (Onsala Space Observatory)
for the Euro VLBI team

We observed the near-IR transient (Yoshida et al., GCN 20784
Not found
 
 
) within
the error circle of AGL J1914+1043 (Tavani et al., GCN 20754
Not found
 
 
) with
the real-time very long baseline interferometry (e-VLBI) technique
using the EVN at 4.9 GHz between 2:06���11:48 UT on 24 March 2017.
There is no compact radio emission detected on milliarcsecond scales
within +-4 arcseconds of the near-IR transient coordinates of
RA=19:10:31.46, DEC=+07:53:52.0, with a 6 sigma upper limit of
105 microJy/beam.

More details on the Euro VLBI team observations:
Participating EVN telescopes were Effelsberg, Irbene, Jodrell Bank MkII,
Medicina, Onsala, Noto, Torun, Westerbork (single dish), Yebes,
Arecibo, Hartebeesthoek and Tianma. The observing frequency of 4.9 GHz
was preferred over 1.6 GHz because of strong scatter-broadening in
this region. The phase-referencing calibrator was J1922+0841, 3 degrees
away from the target; it has resolved structure on mas scales, but
strong fringes were detected. The cycle time was 1:30-3:30 minutes.
Total on-source integration time on the target was 4.1 hours.
A number of other calibrators/calibrator candidates were observed
as well, most notably J1909+0756 (11 arcminutes from the target),
that was detected as a ~30 mJy but quite resolved source (~10 mas
East-West; not useful as calibrator beyond 10 Mlambda at this frequency).
None of the sources reported by Medicina single dish observations at
5 GHz (Pilia et al., GCN 20869
Not found
 
 
) were detected (we had 3 times 1-minute
scans on each). The data were correlated real-time with the
EVN Software Correlator at JIVE (SFXC) and processed according to
standard procedures, using measured system temperature for most
telescopes (for Arecibo, Noto, Jodrell Bank we used nominal SEFDs).

The EVN is a joint facility of independent European, African, Asian,
and North American radio astronomy institutes. Scientific results
from data presented in this publication are derived from the following
EVN project code: RP027.