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Quasar Winds as Dust Factories at High Redshift
Martin Elvis, Massimo Marengo, Margarita Karovska
Winds from AGN and quasars will form large amounts of dust, as the cool gas in these winds passes through the (pressure, temperature) region where dust is formed in AGB stars. Cond…
Rapid N_H Changes in NGC 4151
S. Puccetti, G. Risaliti, F. Fiore +4
We have analyzed two long BeppoSAX observations of the bright Seyfert galaxy NGC 4151, searching for short timescale (10-200 ksec) X-ray spectral variability. The light curve of a…
Quasar Atmospheres: Toward a "Low" Theory for Quasars
Martin Elvis
After 40 years we have no "low" theory of quasars to predict the atomic absorption and emission features so abundant in quasar spectra. Here I take the first step, using results se…
Spatially Resolved Circumnuclear Dust in Centaurus A
Margarita Karovska, Massimo Marengo, Martin Elvis +6
In this paper we present results from our exploratory mid-IR study of Centaurus A circumnuclear environment using high-angular resolution imaging at the Magellan 6.5m telescope wit…
X-Ray Sources Overdensity Around the 3C 295 Galaxy Cluster
V. D'Elia, F. Fiore, M. Elvis +4
We present a statistical analysis of the Chandra observation of the source field around the 3C 295 galaxy cluster (). The logN-logS of this field is in good agreement with…
X-Ray Sources Overdensity Around 3C 295
V. D'Elia, F. Fiore, M. Elvis +4
We present a statistical analysis of the Chandra observation of the source field around the 3C 295 galaxy cluster (). Three different methods of analysis, namely a chip by…
Long term X-ray spectral variability of the nucleus of M81
V. La Parola, G. Fabbiano, M. Elvis +3
We have analysed the soft X-ray emission from the nuclear source of the nearby spiral galaxy M81, using the available data collected with ROSAT, ASCA, BeppoSAX and Chandra. The sou…
Toward a Self Consistent Model of the Ionized Absorber in NGC 3783
Y. Krongold, F. Nicastro, N. S. Brickhouse +3
We present a detailed model for the ionized absorbing gas evident in the 900 ksec Chandra HETGS spectrum of NGC 3783. The analysis was carried out with PHASE a new tool designed to…
The X-ray absorber of PKS2126-158
Fabrizio Fiore, Martin Elvis, Roberto Maiolino +4
BeppoSAX observed the z=3.27 quasar PKS2126-158 on 1999 May 24-28 when its 2-10keV and 0.1-2.5keV fluxes were 1.1E-11 and 4.4E-12 cgs respectively, a factor of 2 higher than in all…
X-ray emission from GPS/CSS sources
Aneta Siemiginowska, Thomas L. Aldcroft, Jill Bechtold +3
The high spatial resolution of the Chandra X-ray Observatory allows us to study the environment of GPS/CSS sources to within an arcsec of the strong compact core. We present the di…
Chandra Discovery of an X-ray jet and Extended X-ray Structure in z=0.63 quasar, B2 0738+313
Aneta Siemiginowska, Carlo Stanghellini, Gianfranco Brunetti +8
We have made a 30 ksec Chandra observation of the redshift z=0.63 GPS quasar B2 0738+313. We detected X-ray emission from the core and have discovered a 200 kpc (projected on the s…
Ultra-Luminous X-ray Source Populations in Normal Galaxies: a Preliminary Survey with Chandra
P. J. Humphrey, G. Fabbiano, M. Elvis +2
We present results of a Chandra survey of the ultra-luminous X-ray sources (ULX) in 13 normal galaxies, in which we combine source detection with X-ray flux measurement. 22 ULX wer…
XMM-Newton Observations of Two BAL QSOs: Q1246-057 and SBS1542+541
D. Grupe, S. Mathur, M. Elvis
We report on the results of XMM-Newton observations of two Broad Absorption Line Quasars (BAL QSOs), Q1246-057 and SBS 1542+541. Unprecedented sensitivity of XMM allows spectral an…
Distances on Cosmological Scales with VLTI
Margarita Karovska, Martin Elvis, Massimo Marengo
We present here a new method using interferometric measurements of quasars, that allows the determination of direct geometrical distances on cosmic scales. Quasar Broad Emission Li…
A High Resolution Intergalactic Explorer for the Soft X-ray/FUV
Martin Elvis, Fabrizio Fiore, the CWE Team
We present a mission concept for high resolution X-ray spectroscopy with a resolving power, R~6000, (c.f. R=<1000 for Chandra, XMM-Newton). This resolution is physics-driven, since…
Chandra observations of X-ray weak Quasars
G. Risaliti, M. Elvis, R. Gilli +1
We present Chandra observations of 18 spectroscopically selected quasars, already known to be X-ray weak from previous ROSAT observations. All the sources but one are detected by C…
The Far-Infrared Spectral Energy Distributions of X-ray-selected Active Galaxies
J. Kuraszkiewicz, B. J. Wilkes, E. J. Hooper +11
[Abridged] We present ISO far-infrared (IR) observations of 21 hard X-ray selected AGN from the HEAO-1 A2 sample. We compare the far-IR to X-ray spectral energy distributions (SEDs…
The X-ray-faint Emission of the Supermassive Nuclear Black Hole of IC1459
G. Fabbiano, M. Elvis, S. Markoff +6
Chandra observations of the supermassive black hole in the nucleus of IC1459 show a weak [L_X=8x10(40)erg s(-1), 0.3-8keV], unabsorbed nuclear X-ray source, with a slope Gamma=1.88…