Search Publications
Highlights from HST/NICMOS
Schneider, G.
The near-infrared camera and multi-object spectrometer (NICMOS) was installed in the Hubble Space Telescope in February 1997. After 22 months of operation the 110 kg supply of solid N 2, which cooled the NICMOS-3 HgCdTe detectors, was exhausted. The cryostat warmed up leaving the instrument in an electromechanically functional, but scie…
The optical to X-ray spectrum of the broad-line ultrasoft AGN RE J2248-511
Mason, K. O.; Starling, R. L. C.; Romero-Colmenero, E. +1 more
We present a series of monitoring observations of the ultrasoft broad-line Seyfert galaxy RE J2248-511 with XMM-Newton. Previous X-ray observations showed a transition from a very soft state to a harder state five years later. We find that the ultrasoft X-ray excess has re-emerged, yet there is no change in the hard power-law. Reflection models wi…
The entropy in groups a clue to galaxy formation
Mushotzky, Richard
The entropy in the hot X-ray gas in groups of galaxies is a fossil of the process of galaxy formation The amount of entropy in these low mass systems considerably exceeds that predicted from structure formation models. To explain these results requires "extra" energy which is a relic of the process of star formation and active galaxy heating. We p…
Probing diffusion parameters of suprathermal ions near heliospheric shocks
Klecker, B.; Hilchenbach, M.; Kallenbach, R. +1 more
The distribution functions of suprathermal ions in the energy range 35-2000 keV/amu associated with the interplanetary coronal mass ejection of 14-16 July 2000 are analyzed. The ion spectra agree with a theoretical model on momentum diffusion in two-dimensional magnetohydrodynamic turbulence.
Measuring the matter distribution within z = 0.2 cluster lenses with XMM-Newton
Smail, I.; Kneib, J. P.; Czoske, O. +4 more
We present an analysis of seven clusters observed by XMM-Newton as part of our survey of 17 most X-ray luminous clusters of galaxies at z ∼ 0.2 selected for a comprehensive and unbiased study of the mass distribution in massive clusters. Using the public software FTOOLS and XMMSAS we have set up an automated pipeline to reduce the EPIC MOS and pn …
A survey of radio jets with Chandra and HST
Sambruna, Rita M.
Relativistic jets are a common property of radio-loud Active Galactic Nuclei (AGN). Understanding jet physical properties is an essential precursor to understanding the mechanisms of energy transport, and ultimately, how energy is extracted from the central black hole. In this paper, I highlight recent developments from Chandra and HST observation…
Ultraviolet images of galaxies from the Optical Monitor on XMM-Newton
Kaastra, J. S.; Branduardi-Raymont, G.; Kahn, S. M. +3 more
A large number of galaxies, both normal and active, have been observed in ultraviolet light by the Optical Monitor on XMM-Newton. These are some of the deepest wide-field ultraviolet images of these galaxies yet obtained, and in many cases the first collected in this waveband. We present images of five active galaxies, and discuss the potential us…
Some comments on the F ring-Prometheus-Pandora environment
Winter, O. C.; Giuliatti Winter, S. M.
The system formed by the F ring and two close satellites, Prometheus and Pandora, has been analysed since the time that Voyager visited the planet Saturn. During the ring plane crossing in 1995 the satellites were found in different positions as predicted by the Voyager data. Besides the mutual effects of Prometheus and Pandora, they are also dist…