Search Publications
XMM-Newton observation of the bright Seyfert 1 galaxy, MCG+8-11-11
de Rosa, A.; Perola, G. C.; Bianchi, S. +2 more
We report on the XMM-Newton observation of the bright Seyfert 1 galaxy, MCG+8-11-11. Data from the EPIC/p-n camera, the Reflection Gratings Spectrometers (RGS), and the Optical Monitor (OM) were analyzed. The p-n spectrum was fitted well by a power law, a spectrally unresolved Fe Kα line, a Compton reflection component (whose high value, when comp…
The K-band properties of Seyfert 2 galaxies
Zhao, Y.; Melnick, J.; Gu, Q. +1 more
Aims. It is well known that the [O iii]λ5007 emission line and hard X-ray (2-10 keV) luminosities are good indicators of AGN activities and that the near and mid-infrared emission of AGN originates from re-radiation of dusty clouds heated by the UV/optical radiation from the accretion disk. In this paper we present a study of the near-infrared K-b…
First high spectral resolution VUV full-Sun spectrum compared to cool stars
Peter, Hardi
This paper reports the first full-Sun vacuum ultraviolet (VUV) emission line profile originating from the transition region from the chromosphere to the corona. It is based on a raster scan of the whole solar disk using SUMER/SOHO. The full-Sun spectrum has a spectral resolution which allows an investigation of details in the line profile as well …
An INTEGRAL hard X-ray survey of the Large Magellanic Cloud
Götz, D.; Mereghetti, S.; Belloni, T. +2 more
Two observation campaigns in 2003 and 2004 with the INTEGRAL satellite have provided the first sensitive survey of the Large Magellanic Cloud with an imaging instrument in the hard X-ray range (15 keV-10 MeV). The high energy flux and long-term variability of the black hole candidate LMC X-1 was measured for the first time without contamination by…
The magnetic Bp star 36 Lyncis. I. Magnetic and photospheric properties
Petit, P.; Smith, M. A.; Wade, G. A. +8 more
Aims.This paper reports the photospheric, magnetic and circumstellar gas characteristics of the magnetic B8p star 36 Lyncis (HD 79158).
Methods: .Using archival data and new polarised and unpolarised high-resolution spectra, we redetermine the basic physical properties, the rotational period and the geometry of the magnetic field, and the phot…
Imaging extended sources with coded mask telescopes: application to the INTEGRAL IBIS/ISGRI instrument
Terrier, R.; Renaud, M.; Lebrun, F. +4 more
Context: .In coded mask techniques, reconstructed sky images are pseudo-images: they are maps of the correlation between the image recorded on a detector and an array derived from the coded mask pattern.
Aims: .The INTEGRAL /IBIS telescope provides images where the flux of each detected source is given by the height of the local peak in the co…
THEMIS/MSDP magnetic field measurements
Schmieder, B.; Berlicki, A.; Mein, P.
We present an analysis of longitudinal magnetic field measurements using the spectral data obtained with the French - Italian polarisation free telescope THEMIS working in Multichannel Subtractive Double Pass (MSDP) mode. We also used SOHO/MDI data to extend our analysis. THEMIS observations in the MSDP mode allows us to perform imaging spectropol…
Hipparcos astrometric orbits for two brown dwarf companions: HD 38529 and HD 168443
Quirrenbach, A.; Reffert, S.
Context: .HD 38529 and HD 168443 have previously been identified as systems with two substellar companion candidates using precise radial velocity measurements.Aims.We want to further constrain their orbits and the nature of the outer companions.Methods.We fit astrometric orbits of the outer substellar companions in the two systems to the Hipparco…
Optical/near-infrared observations of the black hole candidate XTE J1720-318 : from high-soft to low-hard state
Chaty, S.; Bessolaz, N.
Aims.To gain a better understanding of high-energy Galactic sources, we observed the Galactic X-ray binary and black hole candidate XTE J1720-318 in the optical and near-infrared, just after the onset of its X-ray outburst in January, 2003. These observations were obtained with the ESO/NTT as the Target of Opportunity, in February and April 2003.<…
The intensity contrast of solar photospheric faculae and network elements. II. Evolution over the rising phase of solar cycle 23
Sanahuja, B.; Ortiz, A.; Domingo, V.
We studied the radiative properties of small magnetic elements (active region faculae and the network) during the rising phase of solar cycle 23 from 1996 to 2001, determining their contrasts as a function of heliocentric angle, magnetogram signal, and the solar cycle phase. We combined near-simultaneous full disk images of the line-of-sight magne…