CYGNUS X3 INTEGRAL observed

1
First results from
D. Hannikainen, O. Vilhu, J. Huovelin, S.
Maisala, P. Hakala, L. Hjalmarsdotter, P. Muhli
J. Schultz Observatory, PO Box 14, FIN-00014
University of Helsinki, Finland J. Rodriguez,
ISDC, Versoix, Switzerland
CYGNUS X-3 INTEGRAL observed the Cygnus region
during its revolution 23 in December 2002. The
lefthand figure shows this region as seen with
IBIS and just visible left of center is Cygnus
X-3. The righthand side shows the JEM X-2
lightcurve (diamonds) together with the
RXTE/PCA (crosses), showing good agreement
between the two. The cluster of symbols around
phase 0.4 may be due to instrumental effects.
GRS 1915105 PLUS A NEW SOURCE ! !
During a 100 ksec Guest Observer observation of
the well-known Galactic microquasar GRS 1915105
(PI Hannikainen, see poster by Hannikainen
Vilhu) a new source appeared in the
field-of-view about 1 degree away. The source
was detected up to 100 keV and was variable on
timescales of 2000 seconds. Both
characteristics clearly indicate an X-ray binary,
most probably a black hole. The detection of
this new source shows INTEGRALs capability of
discovering new transients in our Galaxy.
Above The field of GRS 1915105 showing the new
source just to the left of the main source.
Left A mosaic image in the 15-40 keV range
showing all the sources in the field-of-view.
Both GRS 1915105 and IGRJ 19140098 are clearly
visible. Right The 15-40 keV lightcurve of IGRJ
19140098 showing variability.