IAU Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8323: Poss. N IN Oph; 2001em; C/2001 Q4

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 8322  SEARCH Read IAUC 8324

View IAUC 8323 in .dvi or .ps format.
IAUC number

                                                  Circular No. 8323
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

     H. Yamaoka, Kyushu University, reports the discovery of a
possible nova (mag about 11.1) by Akira Takao (Kitakyushu, Japan)
on unfiltered CCD images taken on Apr. 14.80 UT, the position given
as R.A. = 17h39m00s, Decl. = -23o28'.5 (equinox 2000.0; uncertainty
>/= 10").  Nothing was visible at this location on his images taken
on 2002 Mar. 18-2004 Mar. 31 (limiting mag 11.9).  S. Nakano,
Sumoto, Japan, forwards the following precise position measured by
K. Itagaki (Teppo-cho, Japan) from his unfiltered CCD image taken
with a 0.60-m reflector on Apr. 15.684 (when the new object
appeared at mag 10.2):  R.A. = 17h38m45s.49, Decl. = -23o28'18".5.
Nothing obvious appears near this position on the Digitized Sky
Survey.  The closest star in the USNO-A2.0 catalogue is a very red
object (red mag 17.2) with position end figures 45s.367, 17".56.
A. Price, AAVSO, notes that ASAS-3 data show the new object at V =
10.9 on Apr. 14.31.

SUPERNOVA 2001em IN UGC 11794
     D. Pooley and W. H. G. Lewin, Massachusetts Institute of
Technology, report the detection of x-ray emission (154 counts)
from the type-Ib/c supernova 2001em (IAUC 7722, 7737, 8282) with
the Chandra x-ray observatory.  A 14600-s ACIS-S3 observation on
Apr. 4.81 UT revealed a source at R.A. = 21h42m23s.60, Decl. =
+12o29'50".3 (equinox 2000.0; +/- 0".5 in each coordinate), in
close agreement with the reported optical and radio positions.
Preliminary spectral fits (using either a MEKAL or power-law model)
indicate a hard spectrum (MEKAL temperature above the model limit
of kT = 80 keV or power-law photon index of 1.1) with a fitted
column density of N_H approximately equal to 1.6 x 10**21 cm**-2.
The unabsorbed 0.5-8-keV luminosity calculated from both models
agrees well and is roughly 10**41 erg/s (for a distance of 80 Mpc).
This high x-ray luminosity (the second highest ever reported for a
young supernova) could indicate a substantial amount of
circumstellar interaction.  Further observations at other
wavelengths are encouraged.

COMET C/2001 Q4 (NEAT)
     Recent visual total-magnitude and coma-diameter estimates:
Apr. 7.93 UT, 5.3, 14' (A. Amorim, Florianopolis, Brazil, 7x50
binoculars); 9.45, 5.6, 12' (A. Pearce, Kalgoorlie, W. Australia,
8x40 binoculars); 10.40, 5.2, -- (D. A. J. Seargent, The Entrance,
N.S.W., 10x50 binoculars); 13.91, 4.9, 15' (Amorim); 14.86, 5.0,
11' (Pearce, Nedlands, W. Australia).

                      (C) Copyright 2004 CBAT
2004 April 15                  (8323)            Daniel W. E. Green

Read IAUC 8322  SEARCH Read IAUC 8324

View IAUC 8323 in .dvi or .ps format.

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

Valid HTML 4.01!