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Related papers: Accretion Stream Mapping

200 papers

A model for advection-dominated accretion flows (ADAFs) in a global magnetic field is proposed. In contrast to the well known ADAF models in which the viscosity of a fluid determines both angular momentum transfer and energy dissipation in…

Astrophysics · Physics 2009-10-31 Osamu Kaburaki

The study of many astrophysical flows requires computational algorithms that can capture high Mach number flows, while resolving a large dynamic range in spatial and density scales. In this paper we present a novel method, RAM: Rapid…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 Pablo Benítez-Llambay , Leonardo Krapp , Ximena S. Ramos , Kaitlin M. Kratter

The availability of the unprecedented spectral resolution provided by modern X-ray observatories is opening up new areas for study involving the coupled formation of the continuum emission and the cyclotron absorption features in…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Brent F. West , Kenneth D. Wolfram , Peter A. Becker

We present a novel automatic adaptive aperture photometry algorithm for measuring the total magnitudes of merging galaxies with irregular shapes. First, we use a morphological pattern recognition routine for identifying the shape of an…

Instrumentation and Methods for Astrophysics · Physics 2017-02-08 Jen-Chao Huang , Chorng-Yuan Hwang

We consider the behavior of matter in the accretion column that emerges under accretion in binary systems near the surface of a white dwarf. The plasma heated in a standing shock wave near the white dwarf surface efficiently radiates in the…

High Energy Astrophysical Phenomena · Physics 2013-12-18 Andrey Semena , Mikhail Revnivtsev

Observations of the fluorescent Fe K-alpha emission line from the inner accretion flows of stellar mass black holes in X-ray binaries and supermassive black holes in Active Galactic Nuclei have become an important tool to study the…

High Energy Astrophysical Phenomena · Physics 2017-11-15 H. Krawczynski , B. Beheshtipour

We report the completion of a survey of radio-loud AGNs begun in an earlier paper, aimed finding and studying broad, double-peaked Balmer lines. We present Ha spectra of 13 broad-lined objects (3 with double-peaked Ha profiles). The final…

Astrophysics · Physics 2009-11-10 M. Eracleous , J. P. Halpern

Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced through plasma-atom and plasma-molecule interactions. Experimental research in how…

This paper provides a mathematical analysis of ultrafast ultrasound imaging. This newly emerging modality for biomedical imaging uses plane waves instead of focused waves in order to achieve very high frame rates. We derive the point spread…

Numerical Analysis · Mathematics 2017-01-09 Giovanni S. Alberti , Habib Ammari , Francisco Romero , Timothée Wintz

In ideal MHD, shear Alfv\'{e}n eigenmodes may experience dissipationless damping due to resonant interaction with the shear Alfv\'{e}n continuum. This continuum damping can make a significant contribution to the overall growth/decay rate of…

Plasma Physics · Physics 2015-07-09 G. W. Bowden , M. J. Hole , A. Könies

Prompted by the recent discovery of pulsed emission from an ultra-luminous X-ray source, M82 X-2 ("ULX-pulsar"), we perform a two-dimensional radiation-hydrodynamic simulation of a super-critical accretion flow onto a neutron star through a…

High Energy Astrophysical Phenomena · Physics 2016-09-09 Tomohisa Kawashima , Shin Mineshige , Ken Ohsuga , Takumi Ogawa

We present a broadly applicable in situ method for profiling ion beams using electrostatic deflectors and a Faraday cup. By deconvolving the detector geometry from the resulting current profiles, spatially resolved absolute current density…

We analyze the ratios of the broad hydrogen Balmer emission lines (from H\alpha to H\epsilon) in the context of estimating the physical conditions in the broad line region (BLR) of active galactic nuclei (AGN). The Balmer emission lines are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 D. Ilic , L. C. Popovic , G. La Mura , S. Ciroi , P. Rafanelli

The paper presents an algorithm for depth map estimation from the light field images in relatively small amount of time, using only single thread on CPU. The proposed method improves existing principle of line fitting in 4-dimensional light…

Computer Vision and Pattern Recognition · Computer Science 2018-05-02 Yuriy Anisimov , Didier Stricker

A Bayesian model to infer edge electron density profiles is developed for the JET lithium beam emission spectroscopy system, measuring Li I line radiation using 26 channels with ~1 cm spatial resolution and 10~20 ms temporal resolution. The…

Plasma Physics · Physics 2017-02-01 Sehyun Kwak , J. Svensson , M. Brix , Y. -c. Ghim

This paper presents a new resolution strategy for multi-scale streamer discharge simulations based on a second order time adaptive integration and space adaptive multiresolution. A classical fluid model is used to describe plasma…

Numerical Analysis · Mathematics 2012-04-10 Max Duarte , Zdenek Bonaventura , Marc Massot , Anne Bourdon , Stéphane Descombes , Thierry Dumont

Idealized and comprehensive ocean models at low resolutions cannot reproduce nominally-resolved flow structures similar to those presented in the high-resolution solution. Although there are various underlying physical reasons for this,…

Fluid Dynamics · Physics 2023-05-24 Igor Shevchenko , Pavel Berloff

We present an analysis of high-speed u- and r-band photometry of the eclipsing polar HU Aquarii that was obtained with ULTRACAM mounted on the VLT. The observations were performed during a low state, permitting us for the first time to…

Solar and Stellar Astrophysics · Physics 2025-12-16 A. D. Schwope , T. R. Marsh , S. G. Parsons , J. Vogel , V. S. Dhillon

We report the discovery of water maser emission in five active galactic nuclei (AGN) with the 100-m Green Bank Telescope (GBT). The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions…

Astrophysics · Physics 2008-11-26 Paul T. Kondratko , Lincoln J. Greenhill , James M. Moran

Recently, Narayan & Raymond (1999) proposed that the thermal emission lines from the hot plasma in advection dominated accretion flows (ADAFs) are potentially observable with the next generation of X-ray observatories, with which the…

Astrophysics · Physics 2007-05-23 Xinwu Cao , Y. D. Xu , J. H. You