Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8050: XTE J1720-318; C/2002 V1; 2003I

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 8049  SEARCH Read IAUC 8051

View IAUC 8050 in .dvi or .ps format.
IAUC number

                                                  Circular No. 8050
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)

XTE J1720-318
     R. A. Remillard, A. M. Levine, and E. H. Morgan, Massachusetts
Institute of Technology (MIT); and E. Smith and J. Swank, Goddard
Space Flight Center (GSFC), for the RXTE All Sky Monitor Team at
MIT and NASA's GSFC, report the discovery of a transient x-ray
source at R.A. = 17h19m58s, Decl. = -31o46'.8 (equinox 2000.0;
estimated 3' uncertainty at 90-percent confidence): "The source was
first detected on 2003 Jan. 9, when the average flux (2-12 keV) was
130 +/- 20 mCrab.  The intensity increased to 430 +/- 40 mCrab on
Jan. 10, and to 400 +/- 20 mCrab on Jan. 13.  A brief observation
of the ASM position on Jan. 14 with the RXTE PCA confirms the
presence of a bright transient.  More extensive observations with
the PCA and HEXTE, including raster scans to improve the source
position, are planned starting Jan. 15.  The error circle does not
contain any noteworthy sources in the Simbad catalogs.  The ASM
hardness ratios indicate that the spectrum was moderately hard
during Jan. 9-10 and relatively soft on Jan. 13.  These results
resemble the early spectral evolution of x-ray transients known to
contain an accreting black hole.  We encourage optical and radio
observations of this new transient."

COMET C/2002 V1 (NEAT)
     M. L. Sitko, University of Cincinnati; and D. K. Lynch, R. W.
Russell, and D. Kim, The Aerospace Corporation, report that 3-14-
micron spectroscopy of C/2002 V1 (NEAT), obtained on Jan. 9.2 UT
with the Aerospace Broadband Array Spectrograph System at the NASA
Infrared Telescope Facility 3-m reflector, revealed a thermal-
emission spectrum showing a trapezoidal-shaped silicate emission
feature with shoulders at 9.0 and 11.2 microns.  The underlying
continuum was well fitted with a 290-K black body, approximately 14
percent above the black-body radiative equilibrium temperature of
254 K.  Narrow-band magnitudes (+/- 0.1) in a 3".5-diameter
aperture were M [4.5 microns] = 8.5 and N [10.2 microns] = 3.1.  On
the following night, the comet was about 10 percent brighter, but
otherwise unchanged.

     T. Kobayashi, Oizumi, Gunma-ken, Japan, reports (via S. Nakano,
Sumoto, Japan) that SN 2003I appeared at mag 17.8 on an unfiltered
CCD prediscovery image taken on Jan. 8.604 UT with a 0.41-m f/4.3

                      (C) Copyright 2003 CBAT
2003 January 15                (8050)            Daniel W. E. Green

Read IAUC 8049  SEARCH Read IAUC 8051

View IAUC 8050 in .dvi or .ps format.

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

Valid HTML 4.01!