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Chandra LETGS and XMM-Newton observations of NGC 4593
Kaastra, J. S.; Behar, E.; Sako, M. +6 more
In this paper, we analyze spectra of the Seyfert 1 galaxy NGC 4593 obtained with the Chandra Low Energy Transmission Grating Spectrometer (LETGS), the Reflection Grating Spectrometer (RGS) and the European Photon Imaging Camera's (EPIC) onboard of XMM-Newton. The two observations were separated by ~ 7 months. In the LETGS spectrum we detect a high…
On variation of the latitudinal structure of the solar convection zone
Thompson, M. J.; Antia, H. M.; Chitre, S. M.
The latitudinal sound-speed structure of the Sun's convection zone gives insight into the physical processes occurring there, specifically the cellular convection and possibly the presence of magnetic fields. Using helioseismic data from the GONG network and MDI instrument on SOHO, we map the latitudinal acoustic structure of the convection zone f…
XMM-Newton observations of four high-z quasars
Brinkmann, W.; Ferrero, E.
We present the results of XMM-Newton observations of four high-z quasars, two radio-loud and two radio-quiet. One of the radio-loud objects, PKS 2126-158, clearly shows absorption in excess of the galactic value as claimed before from ASCA and ROSAT observations. For PKS 2149-306 the evidence for excess absorption is only marginal in contrast to p…
XMM-Newton observation of SN 1993J in M 81
Aschenbach, B.; Zimmermann, H. -U.
In April 2001 SN 1993J was observed with both the PN and MOS cameras of the XMM-Newton observatory, resulting in about 7x 104 s of acceptable observation time. Fit results with both the PN and MOS2 camera spectra studying different spectral models are presented. The spectra are best fitted in the energy range between 0.3 and ~ 10 keV by…
Radiation environment along the INTEGRAL orbit measured with the IREM monitor
Favre, P.; Hajdas, W.; Bühler, P. +3 more
The INTEGRAL Radiation Environment Monitor (IREM) is a payload supporting instrument on board the INTEGRAL satellite. The monitor continually measures electron and proton fluxes along the orbit and provides this information to the spacecraft on board data handler. The mission alert system broadcasts it to the payload instruments enabling them to r…
Technetium and the third dredge up in AGB stars. I. Field stars
Lebzelter, T.; Hron, J.
We searched for Tc in a sample of long period variables selected by stellar luminosity derived from Hipparcos parallaxes. Tc, as an unstable s-process element, is a good indicator for the evolutionary status of stars on the asymptotic giant branch (AGB). In this paper we study the occurrence of Tc as a function of luminosity to provide constraints…
SPI-specific analysis method and software overview
Knödlseder, J.; von Kienlin, A.; Schanne, S. +13 more
The SPI spectrometer on INTEGRAL features a camera system with 19 Ge detector modules, imaging photons through a tungsten coded mask. Background is reduced by an anticoincidence detector system surrounding these. The specifics of this instrument lead to data correction and analysis methods which are described here. Raw data for science analysis ar…
Mid-IR emission of galaxies in the Virgo cluster III. The data
Sauvage, M.; Boselli, A.; Gavazzi, G. +2 more
We present ISOCAM imaging data at 6.75 and 15 mu m for 145 galaxies in the Virgo cluster and in the Coma/A1367 supercluster. Of these, 99 form a complete, optically-selected, volume-limited sample including galaxies in the core and in the periphery of the Virgo cluster, suitable for statistical analysis. 34 of the Virgo galaxies were resolved by I…
X-ray spectroscopy of the cluster of galaxies PKS 0745-191 with XMM-Newton
Böhringer, H.; Chen, Y.; Ikebe, Y.
We present the results from XMM-Newton observations of the cluster of galaxies
Searching for unknown open clusters in the Tycho-2 catalog
Moitinho, A.; Dias, W. S.; Alessi, B. S.
We present 11 new open cluster candidates found in a systematic search for unknown star clusters using the astrometric and photometric data included in the Tycho 2 catalog. The possible existence of these stellar aggregates is supported by the analysis of proper motions, color-magnitude diagrams, stellar density distributions, and by the visual in…