Mass Loss by X-ray Winds from Active Galactic Nuclei (2008)
We consider a sample of type-I active galactic nuclei (AGN) that were observed by Chandra/HETG and resulted in high signal-to-noise grating spectra, which we study in detail. All objects show...
Cosmic Analogues of the Stern-Gerlach Experiment and the Detection of Light Bosons (2008)
Chelouche, Doron, Guendelman, Eduardo I.
We show that, by studying the arrival times of radio pulses from highly-magnetized pulsars, it may be possible to detect light spin-0 bosons (such as axions and axion-like particles) with a much...
Spectroscopic Constraints on (pseudo-)Scalar Particles from Compact Astrophysical Objects (2008)
Chelouche, Doron, Rabadan, Raul, Pavlov, Sergey, Castejon, Francisco
We propose a new method to search for light (pseudo-)scalar particles in the spectra of compact astrophysical objects such as magnetars, pulsars, and quasars. On accounts of compact astrophysical...
On the connection between metal absorbers and quasar nebulae (2008)
Chelouche, Doron, Ménard, Brice, Bowen, David V., Gnat, Orly
We establish a simple model for the distribution of cool (~10^4 K) gas around L* galaxies using the properties of strong Mg II absorption line systems as observational constraints. Our analysis...
Spectral Signatures of Photon-Particle Oscillations from Celestial Objects (2008)
Chelouche, Doron, Rabadan, Raul, Pavlov, Sergey, Castejon, Francisco
We give detailed predictions for the spectral signatures arising from photon-particle oscillations in astrophysical objects. The calculations include quantum electrodynamic effects as well as those...
On the HI content, dust-to-gas ratio and nature of MgII absorbers (2008)
Ménard, Brice, Chelouche, Doron
We estimate the mean dust-to-gas ratio of MgII absorbers as a function of rest equivalent width W_0 and redshift over the range 0.5
The Dust Content of Galaxy Clusters (2007)
Chelouche, Doron, Koester, Benjamin P., Bowen, David V.
We report on the detection of reddening toward z ~ 0.2 galaxy clusters. This is measured by correlating the Sloan Digital Sky Survey cluster and quasar catalogs and by comparing the photometric and...
Heating by Acoustic Waves of Multiphase Media (2007)
We study the emission and dissipation of acoustic waves from cool dense clouds in pressure equilibrium with a hot, volume-filling dilute gas component. In our model, the clouds are exposed to a...
On the Connection Between Metal Absorbers and Quasar Nebulae (2007)
Chelouche, Doron, Ménard, Brice, Bowen, David V., Gnat, Orly
We establish a simple model for the distribution of cold gas around L* galaxies using a large set of observational constraints on the properties of strong MgII absorber systems. Our analysis suggests...
Lensing, reddening and extinction effects of MgII absorbers from z=0.4 to z=2 (2007)
Ménard, Brice, Nestor, Daniel, Turnshek, David, Quider, Anna, Richards, Gordon, Chelouche, Doron, ...
Using a sample of almost 7000 strong MgII absorbers with 0.4 < z < 2.2 detected in the SDSS DR4 dataset, we investigate the gravitational lensing and dust extinction effects they induce on background...
QSO Absorption Lines from QSOs (2006)
Bowen, David V., Hennawi, Joseph F., Menard, Brice, Chelouche, Doron, Inada, Naohisa, Oguri, Masamune, ...
We present the results of a search for metal absorption lines in the spectra of background QSOs whose sightlines pass close to foreground QSOs. We detect MgII(2796,2803) absorption in Sloan Digital...
XMM-Newton Spectroscopy of the Starburst Dominated Ultra Luminous Infrared Galaxy NGC 6240 (2005)
Netzer, Hagai, Lemze, Doron, Kaspi, Shai, George, I. M., Turner, T. J., Lutz, D., ...
We present new XMM-Newton observation of the Ultra Luminous Infrared Galaxy (ULIRG) NGC 6240. We analyze the reflecting grating spectrometer (RGS) data, and data from the other instruments, and find...
Gravitational Microlensing and the Structure of Quasar Outflows (2005)
We show that invaluable information on the structure of quasar outflows can be obtained by considering microlensing (ML) induced variability of absorption line troughs in lensed quasars. Depending on...
Dynamical and Spectral Modeling of the Ionized Gas and Nuclear Environment in NGC 3783 (2005)
Chelouche, Doron, Netzer, Hagai
We present a new approach for calculating the physical properties of highly ionized X-ray flows in active galactic nuclei (AGN). Our method relies on a detailed treatment of the structure, dynamics...
XMM-Newton spectroscopy of the starburst-dominated ultraluminous infrared galaxy NGC 6240 (2005)
Netzer, Hagai, Lemze, Doron, Kaspi, Shai, George, I. M., Turner, T. J., Lutz, D., ...
The Properties and the Evolution of the Highly Ionized Gas in MR2251-178 (2004)
Kaspi, Shai, Netzer, Hagai, Chelouche, Doron, George, Ian M., Nandra, Kirpal, Turner, T. J.
(abridged) We present the first XMM-Newton observations of the radio-quiet quasar MR2251-178 obtained in 2000 and 2002. The EPIC-pn spectra show a power-law continuum with a slope of 1.6 at high...
Strong Gravitational Lensing and the Structure of Quasar Outflows (2003)
We show that by analyzing the spectra of lensed broad absorption line quasars (BALQSOs), it is possible to reveal key properties of the outflowing gas in the inner regions of these objects. This...
Continuum Shielding and Flow Dynamics in Active Galactic Nuclei (2003)
Chelouche, Doron, Netzer, Hagai
We study the ionization, thermal structure, and dynamics of AGN flows which are partially shielded from the central continuum. We utilize detailed non-LTE photoionization and radiative transfer code...
Non-Sobolev modelling of radiation pressure driven flows in Active Galactic Nuclei (2003)
Chelouche, Doron, Netzer, Hagai
We present a new general scheme for calculating the structure and dynamics of radiation pressure driven, photoionized flows. The new method goes one step beyond the Sobolev approximation. It involves...
Radiation Pressure Acceleration by X-rays in Active Galactic Nuclei (2001)
Chelouche, Doron, Netzer, Hagai
We present calculations of the dynamics of highly ionized gas clouds that are confined by external pressure, and are ionized by AGN continuum. We focus on the gas that is seen in absorption in the...