Search Publications
Missions
Journals
Publication Years
The k-filtering technique applied to wave electric and magnetic field measurements from the Cluster satellites
Sahraoui, Fouad; André, Mats; Cornilleau-Wehrlin, Nicole +2 more
The k-filtering technique is a method to characterize stationary fluctuations in space plasmas in terms of the wave energy distribution in the frequency and wave vector space. It has the ability to distinguish between wave modes of the same frequency in the spacecraft frame of reference, but with different wave vectors. This method is based on sim…
Cassini UVIS observations of Jupiter's auroral variability
Dougherty, Michele K.; West, Robert A.; Gurnett, Donald A. +20 more
The Cassini spacecraft Ultraviolet Imaging Spectrograph (UVIS) obtained observations of Jupiter's auroral emissions in H 2 band systems and H Lyman- α from day 275 of 2000 (October 1), to day 81 of 2001 (March 22). Much of the globally integrated auroral variability measured with UVIS can be explained simply in terms of the rotation of …
SDSS J140228.22+632133.3: A New Spectroscopically Selected Gravitational Lens
Treu, Tommaso; Koopmans, Léon V. E.; Bolton, Adam S. +2 more
We present Gemini integral-field unit spectroscopy and Hubble Space Telescope (HST) F435W- and F814W-band images of a newly discovered four-image gravitational lens, SDSS J140228.22+632133.3 (hereafter SDSSJ1402). The system is the first of 49 spectroscopically selected gravitational lens candidates to be imaged with the Advanced Camera for Survey…
The HST view of the nuclear emission line region in low luminosity radio-galaxies
Capetti, A.; Chiaberge, M.; Verdoes Kleijn, G.
We study the properties of the emission line regions in two samples of low luminosity radio-galaxies, while focusing on the Compact Emission Line Region (CELR) revealed to be a characteristic feature of these objects by HST narrow-band imaging. We find a strong correlation between line and optical continuum nuclear emission, which suggests that th…
A Chandra observation of the X-ray environment and jet of 3C 296
Hardcastle, M. J.; Birkinshaw, M.; Worrall, D. M. +2 more
We have observed the twin-jet radio galaxy 3C 296 with Chandra. X-ray emission is detected from the nucleus, from the inner parts of the radio jet and from a small-scale thermal environment around the jet deceleration region. As we have found in previous observations of other twin-jet radio galaxies, the X-ray jet and a steep pressure gradient in …
Submillimetre detection of a high-redshift type 2 QSO
Dunlop, J. S.; Rigopoulou, D.; Tozzi, P. +6 more
We report on the first SCUBA detection of a type 2 QSO at z= 3.660 in the Chandra Deep Field South. This source is X-ray-absorbed, shows only narrow emission lines in the optical spectrum and is detected in the submillimetre: it is the ideal candidate in an evolution scheme for active galactic nuclei (AGN) (e.g. Fabian 1999; Page et al. 2004) of a…
The Acoustic Showerglass. II. Imaging Active Region Subphotospheres
Braun, D. C.; Lindsey, Charles
Seismic diagnostics of the shallow subphotospheres of strong active regions are substantially impacted by large amplitude and phase perturbations introduced by overlying surface magnetic fields. These function as an ``acoustic showerglass'' that impairs the coherence of acoustic waves impinging onto the solar surface from below, degrading images o…
The X-Ray Properties of M101 ULX-1 = CXOKM101 J140332.74+542102
Mukai, K.; Kuntz, K. D.; Corbet, R. H. D. +2 more
We report our analysis of X-ray data on M101 ULX-1, concentrating on high-state Chandra and XMM-Newton observations. We find that the high state of M101 ULX-1 may have a preferred recurrence timescale. If so, the underlying clock may have periods around 160 or 190 days, or possibly around 45 days. Its short-term variations resemble those of X-ray …
Type 2 Counterparts of Narrow-Line Seyfert 1 Galaxies
Dewangan, G. C.; Griffiths, R. E.
Unified models based on viewing angle successfully explain the observed differences between type 1 and type 2 Seyfert galaxies. The existence of a range in accretion rates (m˙~0.001-1) relative to the Eddington rate (from broad-line Seyfert 1's to narrow-line Seyfert 1's, or NLS1's) and the unification of Seyfert galaxies imply that there must be …
Fluorescent Molecular Hydrogen Emission in IC 63: FUSE, Hopkins Ultraviolet Telescope, and Rocket Observations
France, K.; Feldman, P. D.; Andersson, B. -G. +1 more
We present far-ultraviolet observations of IC 63, an emission/reflection nebula illuminated by the B0.5 IV star γ Cas, located 1.3 pc from the nebula. Molecular hydrogen fluorescence was detected first in IC 63 by IUE and later at shorter wavelengths by ORFEUS. Here we present Far Ultraviolet Spectroscopic Explorer (FUSE) observations toward three…