Search Publications
INTEGRAL survey of the Cassiopeia region in hard X rays
Vink, J.; Kuiper, L.; Hermsen, W. +3 more
We report on the results of a deep 1.6 Ms INTEGRAL observation of the Cassiopeia region performed from December 2003 to February 2004. Eleven sources were detected with the imager IBIS-ISGRI at energies above 20 keV, including three new hard X-ray sources. Most remarkable is the discovery of hard X-ray emission from the anomalous X-ray pulsar 4U 0…
Properties of the energetic particle distributions during the October 28, 2003 solar flare from INTEGRAL/SPI observations
Kiener, J.; Tatischeff, V.; Weidenspointner, G. +1 more
Analysis of spectra obtained with the gamma-ray spectrometer SPI onboard INTEGRAL of the GOES X17-class flare on October 28, 2003 is presented. In the energy range 600 keV-8 MeV three prominent narrow lines at 2.223, 4.4 and 6.1 MeV, resulting from nuclear interactions of accelerated ions within the solar atmosphere could be observed. Time profile…
Plateau de Bure interferometer observations of the disk and outflow of HH 30
Pety, J.; Gueth, F.; Guilloteau, S. +1 more
Context: .HH 30 is a well-known Pre-Main-Sequence star in Taurus. HST observations have revealed a flared, edge-on disk driving a highly-collimated optical jet, making this object a case study for the disk-jet-outflow paradigm.
Aims: .We searched for a molecular outflow, and attempted to better constrain the star and disk parameters.
Metho…
On the intensity and spatial morphology of the 511 keV emission in the Milky Way
Prantzos, N.
The positron emissivity of the Galactic bulge and disk, resulting from radioactivity of SNIa, is reassessed in the light of a recent evaluation of the SNIa rate. It is found that the disk may supply more positrons than required by recent observations, but the bulge (where the characteristic e+ annihilation line at 511 keV is in fact obs…
VLT/GIRAFFE spectroscopic observations of the metal-poor blue compact dwarf galaxy SBS 0335-052E
Schaerer, D.; Royer, F.; Izotov, Y. I. +3 more
Aims.We present two-dimensional spectroscopy of the extremely metal-deficient blue compact dwarf (BCD) galaxy SBS 0335-052E to study physical conditions, element abundances and kinematical properties of the ionised gas in this galaxy.
Methods: .Observations were obtained in the spectral range λ3620-9400 Å with the imaging spectrograph GIRAFFE …
Probing isotopic ratios at z = 0.89: molecular line absorption in front of the quasar PKS 1830-211
Combes, F.; Muller, S.; Guélin, M. +2 more
With the Plateau de Bure interferometer, we have measured the C, N, O and S isotopic abundance ratios in the arm of a spiral galaxy with a redshift of 0.89. The galaxy is seen face-on according to HST images. Its bulge intercepts the line of sight to the radio-loud quasar
The host galaxy/AGN connection in nearby early-type galaxies. A new view of the origin of the radio-quiet/radio-loud dichotomy?
Capetti, A.; Balmaverde, B.
This is the third in a series of three papers exploring the connection between the multiwavelength properties of AGN in nearby early-type galaxies and the characteristics of their hosts. Starting from an initial sample of 332 galaxies, we selected 116 AGN candidates requiring the detection of a radio source with a flux limit of ~1 mJy, as measured…
The UV spectrum of HS 1700+6416. II. FUSE observations of the He II Lyman alpha forest
Shull, J. M.; Zheng, W.; Moos, H. W. +11 more
Aims.We present the far-UV spectrum of the quasar
INTEGRAL observation of the high-mass X-ray transient V 0332+53 during the 2005 outburst decline
Rodriguez, J.; Mowlavi, N.; Wilms, J. +7 more
The decline of the high mass X-ray transient V 0332+53 during the Dec. 2004 to Feb. 2005 outburst is analysed from the data recorded by INTEGRAL. The flux is shown to decrease exponentially until 2005 Feb. 10, with a decay time scale of ~30 days above 20 keV and ~20 days at lower energies, and to decrease linearly thereafter. The energy spectrum i…
Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71 . I. Simultaneous broadband observations during November 2003
Lähteenmäki, A.; Smith, N.; Chen, W. P. +72 more
Context.Some intra-day variable, compact extra-galactic radio sources show brightness temperatures severely exceeding 1012 K, the limit set by catastrophic inverse-Compton (IC) cooling in sources of incoherent synchrotron radiation. The violation of the IC limit, actually possible under non-stationary conditions, would lead to IC avalan…