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Related papers: Tests of a Structure for Quasars

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A review of spectroscopic results obtained from Chandra High Energy Transmission Grating Spectrometer and XMM-Newton Reflection Grating Spectrometer observations of several wind-fed high-mass X-ray binaries (HMXBs) is presented. These…

Astrophysics · Physics 2007-05-23 M. Sako , S. M. Kahn , F. Paerels , D. A. Liedahl , S. Watanabe , F. Nagase , T. Takahashi

We present numerical simulations investigating the interaction of AGN jets with galaxy clusters, for the first time taking into account the dynamic nature of the cluster gas and detailed cluster physics. The simulations successfully…

Astrophysics · Physics 2009-11-11 S. Heinz , M. Brueggen , A. Young , E. Levesque

The next decade will be an exciting period for solar astrophysics, as new ground- and space-based instrumentation will provide unprecedented observations of the solar atmosphere and heliosphere. The synergy between modeling effort and…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Serena Criscuoli , Maria Kazachenko , Irina Kitashvili , Alexander Kosovichev , Valentín Martínez Pillet , Gelu Nita , Viacheslav Sadykov , Alan Wray

Quasars are variable and their variability can both constrain their physical properties and help to identify them. We look for ways to efficiently identify quasars exhibiting consistent variability over multi-year time-scales, based on a…

Astrophysics of Galaxies · Physics 2025-07-02 E. A. Zaharieva , V. D. Ivanov , E. P. Ovcharov , O. I. Stanchev

Gamma-rays can be produced by the interaction of a relativistic jet and the matter of the stellar wind in the subclass of massive X-ray binaries known as "microquasars". The relativistic jet is ejected from the surroundings of the compact…

Astrophysics · Physics 2007-08-14 G. E. Romero , S. P. Owocki , A. T. Araudo , R. Townsend , P. Benaglia

The current status of leptonic jet models for blazars is reviewed. Differences between the quasar and BL-Lac subclasses of blazars may be understood in terms of the dominance of different radiation mechanisms in the gamma-ray regime.…

Astrophysics · Physics 2007-05-23 M. Boettcher

A simple, novice-friendly scheme for classifying the image configurations of quadruply lensed quasars is proposed. With only six classes, it is intentionally coarse-grained. It focuses on the kitelikeness and circularity of these…

Astrophysics of Galaxies · Physics 2022-09-07 Paul L. Schechter

While feedback is important in theoretical models, we do not really know if it works in reality. Feedback from jets appears to be sufficient to keep the cooling flows in clusters from cooling too much and it may be sufficient to regulate…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Smita Mathur , Rebecca Stoll , Yair Krongold , Fabrizio Nicastro , Nancy Brickhouse , Martin Elvis

By considering a small sample of core-dominated radio-loud quasars with X-ray jets, I show, as has been argued previously by others, that the observations require bulk jet deceleration if all of the X-ray emission is to be explained using…

Astrophysics · Physics 2009-11-13 M. J. Hardcastle

We have obtained ultra-high quality spectra (R=180,000; S/N>300) with unprecedented wavelength coverage (4400 to 7400 A) for a number of stars covering most of the HR diagram in order to test the predictions of models of stellar surface…

Solar and Stellar Astrophysics · Physics 2009-09-01 I. Ramirez , C. Allende Prieto , D. L. Lambert , L. Koesterke , M. Asplund

Surveys to find high-redshift radio galaxies deliberately exclude optically-bright objects, which may be distant radio-loud quasars. In order to properly determine the space density of supermassive black holes, the fraction of such objects…

Astrophysics · Physics 2009-11-07 Chris Simpson

This brief review focuses on methods and applications of modeling exoplanetary atmospheres. We discuss various kinds of state of the art self-consistent and retrieval models in 1D and multi-D with a focus on open questions and short- and…

Earth and Planetary Astrophysics · Physics 2021-12-15 Jonathan J. Fortney , Joanna K. Barstow , Nikku Madhusudhan

We present results from a combined radio polarization and emission line study of five type 2 quasars at $z<0.2$ with the Karl G. Jansky Very Large Array (VLA) B-array at 5 GHz and Hubble Space Telescope (HST) [O III] observations. These…

Astrophysics of Galaxies · Physics 2022-07-19 Silpa Sasikumar , P. Kharb , C. M. Harrison , A. Girdhar , D. Mukherjee , V. Mainieri , M. E. Jarvis

We report preliminary results from a third sample of quasar absorption line spectra from the Keck telescope which has been studied to search for any possible variation of the fine structure constant, alpha. This third sample, which is…

Astrophysics · Physics 2009-08-18 J. K. Webb , M. T. Murphy , V. V. Flambaum , S. J. Curran

Searches for spacetime variations of fundamental constants have entered an era of unprecedented precision. New, high quality quasar spectra require increasingly refined analytic methods. In this article, a continuation in a series to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-03 John K. Webb , Chung-Chi Lee

In this contribution, we present the StaggerGrid, a collaborative project for the construction of a comprehensive grid of time-dependent, three-dimensional (3D), hydrodynamic model atmospheres of solar- and late-type stars with different…

Solar and Stellar Astrophysics · Physics 2015-05-30 Remo Collet , Zazralt Magic , Martin Asplund

Evidence indicates that supermassive black holes exist at the centers of most galaxies. Their mass correlates with the galactic bulge mass, suggesting a co-evolution with their host galaxies, most likely through powerful winds. X-ray…

High Energy Astrophysical Phenomena · Physics 2025-05-15 XRISM collaboration

In astronomy, there is an opportunity to enhance the practice of validating models through statistical techniques, specifically to account for measurement error uncertainties. While models are commonly used to describe observations, there…

Instrumentation and Methods for Astrophysics · Physics 2023-08-09 Fiorenzo Stoppa , Eric Cator , Gijs Nelemans

Exoplanets are now being discovered in profusion. However, to understand their character requires spectral models and data. These elements of remote sensing can yield temperatures, compositions, and even weather patterns, but only if…

Earth and Planetary Astrophysics · Physics 2015-06-23 Adam Burrows

The classification of jets as quark- versus gluon-initiated is an important yet challenging task in the analysis of data from high-energy particle collisions and in the search for physics beyond the Standard Model. The recent integration of…

High Energy Physics - Phenomenology · Physics 2021-03-17 Alexis Romero , Daniel Whiteson , Michael Fenton , Julian Collado , Pierre Baldi
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