Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 6785: GRB 971208; SNe; 1997dn, 1997dq

The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).


Read IAUC 6784  SEARCH Read IAUC 6786

View IAUC 6785 in .dvi or .ps format.
IAUC number


                                                 Circular No. 6785
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html
Phone 617-495-7244/7440/7444 (for emergency use only)


GRB 971208
     V. Connaughton, National Academy of Sciences/National Research
Council and Marshall Space Flight Center (MSFC); and R. M. Kippen
and R. Preece, University Alabama at Huntsville and MSFC, for the
BATSE team; and K. Hurley, University of California at Berkeley,
for the Ulysses team, write that an unusually long and smooth
single-peaked gamma-ray burst (GRB) was detected by BATSE on the
Compton Gamma-Ray Observatory on Dec. 8.335 UT (trigger 6526) and
was detected also by Ulysses.  A duration of nearly 800 s makes it
longer by an order of magnitude than any other single-peaked GRB
observed by BATSE.  It is also the longest single episode of
emission in a BATSE GRB.  Its intensity rose over an interval of 60
s to a maximum flux of 8.97 +/- 0.3 x 10E-7 erg cmE-2 sE-1 (between
25 and 1800 keV; integration time 2.048 s) and decayed with a power
law of roughly -0.4 over the following 700 s.  The total fluence of
the event above 25 keV is estimated to be 1.86 +/- 0.03 x 10E-4 erg
cmE-2.  The BATSE location centroid for the GRB is R.A. = 23h45m50s,
Decl. = +77o56'.4 (equinox 2000.0) with a 1-sigma statistical error
of 1.2 deg.  A preliminary joint BATSE/Ulysses InterPlanetary
Network annulus is described by a center at R.A. = 23h25m39s, Decl.
= -11o52'.4, with a radius of 87.906 deg (half-width 0.224 deg).  A
sky map of the event is available at
http://www.batse.msfc.nasa.gov/~kippen/batserbr/brbr_obs.html.


SUPERNOVAE
     S. Deustua, Lawrence Berkeley Laboratory (LBL); R. McMillan,
Apache Point Observatory; H. Newberg, Fermi National Accelerator
Laboratory; P. Nugent, C. Pennypacker, and S. Perlmutter, LBL; and
M. Strauss, Princeton University, report redshifts (+/- 0.002) for
the host galaxies of four supernovae announced on IAUC 6782; the
following redshifts were estimated from emission features in
spectra obtained with the 3.5-m ARC Telescope at Sunspot, NM, on
the respective dates:  SN 1997eb, Nov. 23 UT, 0.085; SN 1997ec, 23,
0.124; SN 1997ed, 24, 0.152; SN 1997ee, 29, 0.166.  SN 1997ee is a
normal type-Ia supernova near maximum light, and SN 1997ed may be a
type-II event.


SUPERNOVAE 1997dn AND 1997dq
     Unfiltered CCD magnitude estimates (GSC reference stars) from
S. Moretti and S. Tomaselli, Forli, Italy:  SN 1997dn (cf. IAUC
6763), Dec. 8.02 UT, 16.6; SN 1997dq (cf. IAUC 6770), Dec. 8.04,
16.2.

                      (C) Copyright 1997 CBAT
1997 December 10               (6785)            Daniel W. E. Green

Read IAUC 6784  SEARCH Read IAUC 6786

View IAUC 6785 in .dvi or .ps format.


Our Web policy. Index to the CBAT/MPC/ICQ pages.


Valid HTML 4.01!