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Diffuse radio sources in groups and poor clusters
Rudnick, L.; Delain, K. M.
We have discovered new diffuse radio sources likely associated with groups of galaxies at low redshift (0.01-0.04) and without apparent AGN by using the WENSS and WISH catalogs to perform an unbiased survey. These sources resemble the radio halos, mini-halos, and `relics' of rich clusters, which are thought to be powered by shocks and turbulence f…
Suzaku observation of NGC 3516: complex absorption and the broad and narrow Fe K lines
Miniutti, G.; Reeves, J. N.; Yaqoob, T. +9 more
We present preliminary results from a 150 ks Suzaku observation of the Seyfert 1 galaxy NGC 3516. Suzaku's wide bandpass has enabled us to deconvolve the broadband emitting and absorbing components in this object, breaking model degeneracies inherent in previous, smaller-bandpass spectra. The primary power-law continuum is absorbed by an ionized a…
The iron emission line complex of MCG-5-23-16: the long XMM-Newton look
Ptak, A.; Nandra, K.; Turner, T. J. +9 more
We present the results of the simultaneous XMM-Newton and Chandra observations of the bright Seyfert 1.9 galaxy MCG-5-23-16, which is one of the best known examples of a relativistically broadened iron K\alpha line. We find that: a) the soft X-ray emission is likely to be dominated by photoionized gas, b) the complex iron emission line is best mod…
Light bending models in AGNs
Miniutti, G.
We review the MCG-6-30-15 observations and results that provided the motivation for the light bending model. We present a summary of the main properties of the model and discuss its application to MCG-6-30-15 briefly mentioning other X-ray sources showing the same qualitative behaviour. Finally, we report on one of the most spectacular cases so fa…
An ionized disc reflection component for the X-ray spectrum of NGC 4051 and IRAS13224-3809?
Cappi, M.; Ponti, G.; Fabian, A. C. +2 more
A spectral variability study of the two Narrow Line Seyfert 1 galaxies NGC 4051 and IRAS13224-3809 is presented. Both sources show a high degree of flux and spectral variability. The nuclear emission, lightly absorbed by warm material, has been decomposed into a direct power law emission and an ionized disc reflection plus constant emission from d…
The origin of the strong soft excess and puzzling iron line complex in Mkn 841
Maraschi, L.; Nandra, K.; Ponti, G. +8 more
Mkn 841 has been observed during 3 different periods (January 2001, January 2005 and July 2005) by XMM-Newton for a total cumulated exposure time of ∼108 ks. We present in this paper a broad band spectral analysis of the complete EPIC-pn data sets. These observations confirm the presence of the strong soft excess and complex iron line profile know…
Narrow-Line Seyfert 1 Galaxies with high-energy sharp spectral drops: reflection-versus absorption models
Boller, Th.
With the launch of XMM-Newton in 1999, two Narrow-Line Seyfert 1 Galaxies (NLS1s) have been detected (IRAS 13224-3809 and 1H 0707-495) showing sharp spectral drops at energies equal or above the neutral Fe K edge at 7.1 keV without any narrow Fe K reemission. In this paper I summarize our present knowledge on the observed properties of sharp high-…
The broad iron line physics: summary and outlook
Tanaka, Y.
A brief overview of the ESAC/XMM-Newton Science Operations Centre Workshop on ``Variable and Broad Iron Lines around Black Holes" is presented. Following the relativistic disk-line theory of accreting black holes, ASCA discovered such broad iron lines from several AGN. XMM-Newton and Chandra confirmed the ASCA results, but also found more complexi…
Contribution to the study of binaries with spectral types F, G, K, and M XI. Orbital elements of three red-giant spectroscopic binaries: HR 1304, HR 1908, and HD 126947
Griffin, R. F.; Prieur, J. -L.; Carquillat, J. -M.
The orbital elements of three red-giant single-lined spectroscopic binaries, HR 1304, HR 1908 and HD 126947, are presented. They are obtained from observations made with two photoelectric spectrometers of CORAVEL type, the first located at the Observatoire de Haute-Provence and the second at the Cambridge Observatories. HR 1304 and HR 1908 are kno…
First ground-based photometry and light-curve analysis of the eccentric eclipsing binary V744 Cas
Bulut, İ.; Erdem, A.; Bakis, V. +3 more
The first ground-based BVR photometric observations of the recently discovered eclipsing binary V744 Cas are presented. From these measurements, timings for two primary and one secondary minima have been calculated. The light curves of the system were analyzed by using the Wilson-Devinney program. The analysis shows that the system is detached wit…