Search Publications
The continued spectral and temporal evolution of RX J0720.4-3125
Haberl, F.; de Vries, C. P.; Vink, J. +4 more
RX J0720.4-3125 is the most peculiar object among a group of seven isolated X-ray pulsars (the so-called Magnificent Seven), since it shows long-term variations of its spectral and temporal properties on time-scales of years. This behaviour was explained by different authors either by free precession (with a 7 or 14 yr period) or possibly a glitch…
A phenomenological model for the X-ray spectrum of nova V2491 Cygni
Kaastra, J. S.; Costantini, E.; Ness, J. -U. +3 more
The X-ray flux of nova V2491 Cyg reached a maximum some forty days after optical maximum. The X-ray spectrum at that time, obtained with the RGS of XMM-Newton, shows deep, blue-shifted absorption by ions of a wide range of ionization. We show that the deep absorption lines of the X-ray spectrum at maximum, and those observed nine days later, are w…
Magnetic flux rope formation within a magnetosheath hot flow anomaly
Zhang, H.; Zong, Q. -G.; Lavraud, B. +4 more
We report observations on 1 March 2004 by the Cluster spacecraft of a hot flow anomaly (HFA) encountered in the dayside magnetosheath near Earth's bow shock. Embedded within the HFA was a magnetic flux rope with a diameter of a few thousand km, which was moving sunward and was presumably expanding. The pristine upstream solar wind seen by the ACE …
Two-phase ICM in the Central Region of the Rich Cluster of Galaxies A1795: A Joint Chandra, XMM-Newton, and Suzaku View
Makishima, Kazuo; Nakazawa, Kazuhiro; Xu, Haiguang +7 more
Based on a detailed analysis of the high-quality Chandra, XMM-Newton, and Suzaku data of the X-ray bright cluster of galaxies A1795, we report clear evidence for a two-phase intracluster medium (ICM) structure, which consists of a cool (with a temperature T c ≈ 2.0-2.2 keV) and a hot (T h ≈ 5.0-5.7 keV) component that coexist…
Two-dimensional kinematics of SLACS lenses - IV. The complete VLT-VIMOS data set
Treu, Tommaso; Czoske, Oliver; Koopmans, Léon V. E. +2 more
This paper presents the full Very Large Telescope (VLT)/VIMOS-IFU data set and related data products from an ESO Large Programme with the observational goal of obtaining two-dimensional kinematic data of early-type lens galaxies, out to one effective radius. The sample consists of 17 early-type galaxies (ETGs) selected from the SLACS gravitational…
Solar cycle dependence of the cusp O+ access to the near-Earth magnetotail
Dandouras, I.; Klecker, B.; Kistler, L. M. +2 more
Ionospheric origin O+ accelerated in the cusp/cleft region is one source for the O+ observed in the plasma sheet. This O+ is convected over the polar cap, flowing along open field lines to the tail lobes, and finally entering the plasma sheet. In this paper we use Cluster/CODIF data to study how the occurrence of c…
High-resolution X-Ray Spectroscopy of the Magnetic Of?p Star HD 148937
Walborn, Nolan R.; Zhekov, Svetozar A.; Nazé, Yaël
High-resolution data of the peculiar magnetic massive star HD 148937 were obtained with Chandra-HETGS, and are presented here in combination with a re-analysis of the older XMM-RGS data. The lines of the high-Z elements (Mg, Si, S) were found to be unshifted and relatively narrow (FWHM of about 800 km s-1), i.e., narrower than the O lin…
Solid-phase C60 in the peculiar binary XX Oph?
van Loon, J. Th.; Gehrz, R. D.; Eyres, S. P. S. +8 more
We present infrared spectra of the binary XX Oph obtained with the Infrared Spectrograph on the Spitzer Space Telescope. The data show some evidence for the presence of solid C60- the first detection of C60 in the solid phase - together with the well-known 'unidentified infrared' emission features. We suggest that, in the cas…
Radially extended kinematics in the S0 galaxy NGC 2768 from planetary nebulae, globular clusters and starlight
Cortesi, Arianna; Forbes, Duncan A.; Romanowsky, Aaron J. +7 more
There are only a few tracers available to probe the kinematics of individual early-type galaxies beyond one effective radius. Here we directly compare a sample of planetary nebulae (PNe), globular clusters (GCs) and galaxy starlight velocities out to approximately four effective radii, in the S0 galaxy NGC 2768. Using a bulge-to-disc decomposition…
Bouncing on Titan: Motion of the Huygens probe in the seconds after landing
Karkoschka, Erich; Schröder, Stefan E.; Lorenz, Ralph D.
While landing on Titan, several instruments onboard Huygens acquired measurements that indicate the probe did not immediately come to rest. Detailed knowledge of the probe's motion can provide insight into the nature of Titan's surface. Combining accelerometer data from the Huygens Atmospheric Structure Instrument (HASI) and the Surface Science Pa…