English
Related papers

Related papers: A Quasar Wind Model

200 papers

Many analyses have concluded that the accretion disc sizes measured from the microlensing variability of quasars are larger than the expectations from the standard thin disc theory by a factor of $\sim4$. We propose a simply model by…

High Energy Astrophysical Phenomena · Physics 2018-12-05 Ya-Ping Li , Feng Yuan , Xinyu Dai

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

We present a 3D dynamical model of the orbital induced curvature of the wind-wind collision region in binary star systems. Momentum balance equations are used to determine the position and shape of the contact discontinuity between the…

Astrophysics · Physics 2009-11-13 E. R. Parkin , J. M. Pittard

We propose a statistical space-time model for predicting atmospheric wind speed based on deterministic numerical weather predictions and historical measurements. We consider a Gaussian multivariate space-time framework that combines…

Applications · Statistics 2016-10-21 Julie Bessac , Emil Mihai Constantinescu , Mihai Anitescu

We discuss a general mechanism which allows to explain naturally both radio and high energy emission by pulsars. We also discuss the plasma distribution in the region surrounding the pulsar, the pulsar wind and the formation of jet along…

Astrophysics · Physics 2007-05-23 Paolo Cea

We study the properties of the broad line region in blazars by comparing the virial estimate of black hole masses with that derived from the mass of the host galaxies. The former is sensitive to the width of broad lines, i.e., to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Roberto Decarli , Massimo Dotti , Aldo Treves

Parker's hydrodynamic stellar wind model is extended to polytropic gas flows. A compatible theoretical formulation is given and detailed numerical and systematic asymptotic theoretical considerations are presented. The polytropic conditions…

Solar and Stellar Astrophysics · Physics 2020-07-14 B. K. Shivamoggi , D. K. Rollins

Young pulsars spin incredibly quickly, but are also slowing down at a very rapid rate. This process carries away enormous amounts of energy from the star in the form of a relativistic wind. Through the high resolution now offered by the…

Astrophysics · Physics 2007-05-23 Bryan M. Gaensler

A combined analysis of the profiles of the main broad quasar emission lines in both Hubble Space Telescope and optical spectra shows that while the profiles of the strong UV lines are quite similar, there is frequently a strong increase in…

Astrophysics · Physics 2017-02-22 Stephanie A. Snedden , C. Martin Gaskell

Intensive monitoring campaigns have recently attempted to measure the time delays between multiple images of gravitational lenses. Some of the resulting light-curves show puzzling low-level, rapid variability which is unique to individual…

Astrophysics · Physics 2015-06-24 Stuart Wyithe , Abraham Loeb

One of the most intriguing spectral features of WR binary stars is the presence of time-dependent line profiles. Long term observations of several systems revealed the periodicity of this variability, synchronized with the orbital movement.…

Astrophysics · Physics 2009-11-11 D. Falceta-Goncalves , Z. Abraham , V. Jatenco-Pereira

High resolution spectra of typical wind diagnostics ([OI] 6300 \r{A} and other forbidden emission lines) can often be decomposed into multiple components: high-velocity components with blueshifts up to several 100 km/s are usually…

Solar and Stellar Astrophysics · Physics 2020-06-10 Michael L. Weber , Barbara Ercolano , Giovanni Picogna , Lee Hartmann , Peter J. Rodenkirch

Quasar outflows carry mass, momentum and energy into the surrounding environment, and have long been considered a potential key factor in regulating the growth of supermassive black holes and the evolution of their host galaxies. A crucial…

The kinematics and morphology of the broad emission line region (BELR) of quasars are the subject of significant debate. The two leading methods for constraining BELR properties are microlensing and reverberation mapping. Here we combine…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 H. Garsden , N. F. Bate , G. F. Lewis

We present a general procedure for deriving a line profile model for massive star X-ray spectra that captures the dynamics of the wind more directly. The basis of the model is the analytic solution to the problem of variable jets in…

Solar and Stellar Astrophysics · Physics 2024-04-11 Sean J. Gunderson , Kenneth G. Gayley

The dynamics of the upper mesosphere of Venus (~85-115 km) have been characterized as a combination of a retrograde superrotating zonal wind (RSZ) with a subsolar-to-antisolar flow (SSAS). Numerous mm-wave single-dish observations have been…

Earth and Planetary Astrophysics · Physics 2015-06-04 A. Moullet , E. Lellouch , R. Moreno , M. Gurwell , H. Sagawa

The quasar mode of Active Galactic Nuclei (AGN) in the high-redshift Universe is routinely observed in gas-rich galaxies together with large-scale AGN-driven winds. It is crucial to understand how photons emitted by the central AGN source…

Astrophysics of Galaxies · Physics 2016-09-28 Rebekka Bieri , Yohan Dubois , Joakim Rosdahl , Alexander Y. Wagner , Joseph Silk , Gary A. Mamon

In this paper, the variable wind power is incorporated into the dynamic model for long-term stability analysis. A theory-based method is proposed for power systems with wind power to conduct long-term stability analysis, which is able to…

Systems and Control · Computer Science 2016-11-15 Xiaozhe Wang , Hsiao-Dong Chiang , Jianhui Wang , Hui Liu , Tao Wang

Context. Gamma-ray binaries are systems that radiate the dominant part of their non-thermal emission in the gamma-ray band. In a wind-driven scenario, these binaries are thought to consist of a pulsar orbiting a massive star, accelerating…

High Energy Astrophysical Phenomena · Physics 2021-03-02 David Huber , Ralf Kissmann , Anita Reimer , Olaf Reimer

An accurate and timely assessment of wind speed and energy output allows an efficient planning and management of this resource on the power grid. Wind energy, especially at high resolution, calls for the development of nonlinear statistical…

Applications · Statistics 2024-12-17 Matthew Bonas , Paolo Giani , Paola Crippa , Stefano Castruccio