[vsnet-grb-info 10479] GRB 110407A:VLF observations on 20.27kHz

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11914
SUBJECT: GRB 110407A:VLF observations on 20.27kHz
DATE:    11/04/09 16:17:17 GMT
FROM:    Matus Kocka at AI AS CR, Ondrejov  <kocka.mat at gmail.com>

Matus Kocka (AI AS CR), Rudolf Slosiar (Rudy BASE Observatory
Bojnice), Vladimir Karlovsky (Observatory Hlohovec), Richard Marko (AI
AS CR), Jan Karlovsky (Observatory Hlohovec), Rene Hudec (AI AS CR)


We observed the ionospheric perturbation on Apr. 7th which started at
14:06:21 UT from 3 different VLF receivers, so called SID monitors
(Sudden Ionospheric Disturbance) on ICV channel 20.27kHz. This event
is with a high probability GRB 110407A (Wolf et al., GCN 11895). The
detectors are located in Bojnice (Slovakia), Hlohovec (Slovakia) and
Brno (Czech Republic). Those places are so far apart that we can rule
out a possibility of a local disturbance.

The plot from all three SID-monitors is here:
http://zeus.asu.cas.cz/~koci/grb110407a/GRB110407A_vlf.png

Further analysis is ongoing.