IAU Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits


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 8106  SEARCH Read IAUC 8108

View IAUC 8107 in .dvi or .ps format.
IAUC number

                                                  Circular No. 8107
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)

     S. Starrfield, Arizona State University; J.-U. Ness, Hamburg;
J. J. Drake, Harvard-Smithsonian Center for Astrophysics; and M.
Orio, University of Wisconsin, report, for a much larger
collaboration, that they observed V4743 Sgr for 7 hr beginning at
Mar. 19.396 UT with the Chandra X-ray satellite (+ Low Energy
Transmission Grating Spectrometer + High Resolution Camera):  "The
spectrum is complex, dominated by continuum emission from 2.0 to
4.0 nm (peak around 2.8 nm) with obvious and deep absorption
features.  Assuming a blue shift of -2400 km/s, we tentatively
identify C VI at 3.38 nm and O VII at 2.16 nm and are in the
process of identifying other spectral features.  Our spectrum
(qualitatively, but not quantitatively) resembles the XMM-Newton
spectrum of Cal 83 by Paerels et al. (2001, A.Ap. 365, L308).  It
appears that we are observing the hot atmosphere of the underlying
white dwarf undergoing nuclear burning near the surface.  This nova
is bright at x-ray wavelengths, with a count rate of 40 counts/s
plus large amplitude oscillations of 10 counts/s with a period of
1323 s (preliminary).  There appear to be additional periods
present in the data, suggesting that this might be a pulsation
rather than rotation, and further analysis of the light curve is
ongoing (see also Drake et al. 2003, Ap.J. 584, 448).  Of further
note in the light curve, after 3.6 hr a slow decay occurs; the
counts drop to near zero after about 1.5 hr and remain near zero
for the last 1.5 hr of the observation.  We have a 36500-s
XMM-Newton observation beginning at Apr. 4.921 and urge
contemporaneous ground-based spectroscopic and photometric
observations of this exciting nova."

     P. D. Fieseler and S. M. Ardalan, Jet Propulsion Laboratory,
California Institute of Technology, report the discovery of several
small objects south of Jupiter V in data obtained with the Galileo
spacecraft's star scanner on 2002 Nov. 5.26 UT during its closest
approach.  Assuming that the bodies are < 5 km in diameter, they
all were within about 5000 km of the spacecraft; limited data
prevented the determination of more precise positions.

GRB 030329
     Further to IAUC 8102, J. E. McGaha reports additional
unfiltered CCD magnitudes, calibrated to the R bandpass: Apr. 1.175
UT, 16.7; 1.184, 16.8; 1.208, 17.0; 1.241, 16.9; 1.259, 16.8;
1.261, 17.0; 3.162, 17.9; 1.179, 17.7; 3.188, 17.9; 3.199, 18.0;
4.170, 17.7; 4.191, 17.8; 4.199, 17.6.

                      (C) Copyright 2003 CBAT
2003 April 4                   (8107)            Daniel W. E. Green

Read IAUC 8106  SEARCH Read IAUC 8108

View IAUC 8107 in .dvi or .ps format.

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

Valid HTML 4.01!