Gamma Ray Burst Observations

by Rodney Howe, email ahowe at frii dot com

This page is for posting the potential GRB detection data that I collect, as well as any data posted by other SARA members. I hope I can thus get folks to participate. There was a GRB on November 12, coming from the direction of Perseus. Here are an image of the data and a detail. I seriously doubt that what looks like a GRB in this data, for this time, is the real thing, but it might get folks to looking, and sharing data.

At 03:28:15.89 UTC on 12 November 2002, the HETE FREGATE and WXM instruments detected event H2448, a long GRB. (Click on thumbnail to download full-size image)

 

RA = +02 h 36 m 52 s, Dec = +48 d 50 m 56 s (J2000) (Click on thumbnail to download full-size image)

 

Here are steps I would suggest folks take to get started with GRB or x-ray
transient detection: There is a lot out there on this topic, it is hard to
focus, so I would suggest these lists, if you're not already subscribed:

1). Subscribe to the GCN circular through Aaron Price at AAVSO, email him
and ask to be put on his GCN list where you can get the HETE and upcoming
INTERGRAL alerts:

• aaronp @ aavso.org Subject: AAVSO/GCN CIRCULAR

2). To view the alert archives from GCN distributed via the AAVSO GRB Network:

• http://www.aavso.org/grb/archive/

3). I would also subscribe to the AAVSO/SID group, Casper Hossfield moderates
this list and it has become dedicated to GRB, x-ray transient postings as
well as SID, SES work:

• List-Subscribe: http://mailman.McMaster.CA/mailman/listinfo/aavso-sid-list,
• List-Id: AAVSO SID Discussion List <aavso-sid-list.mailman.McMaster.CA>

4). These are some interesting studies on how the solar wind pushes the
upper ionosphere layers around during the day and nighttime. It seems
during the day the ionosphere gets compressed along with the high energy
ionization, and percipitation of relativistic electrons. It will be a
challenge for those of us who want to detect GRB or x-ray transients to
find the signal in all this noise coming from the Sun.

• http://www-star.stanford.edu/~vlf/spaceweather/spaceweather.htm

5). A most interesting book recently translated: "Flash, The hunt for the
biggest explosions in the universe", by Govert Shcilling, Cambridge
University Press, 2002, (It is also publihsed in Dutch by Uitgeverij
Wereldbibliotheek, Amsterdam, 2000.) The book does not discuss VLF
detection, but it is a well written history of the discoveries of GRB and
Soft Gamma Repeaters.

There are only three groups that I know of currently interested in the VLF
detection: SARA, AAVSO, and NASA. I think AAVSO is further along, although,
folks are recording mostly without computers: they use Rustrack thermal
paper
recorders. The SARA group use computers, but seem to be new to SID
recording.

From NASA, Jerry Fishman, has been kind enough to send a list of
the top 200 GRB detections from the BATSE collector, before it went into
the Pacific. The only folks with data back to 1990 are folks doing SID work
at AAVSO. If you collect VLF data check your data files for any of these
long duration GRBs.