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Related papers: Spiral waves in accretion discs - observations

200 papers

The presence of planetary material in white dwarf atmospheres, thought to be accreted from a dusty debris disc produced via the tidal disruption of a planetesimal, is common. Approximately five per cent of these discs host a co-orbital…

Cataclysmic Variables (CVs) are compact binaries with white dwarf (WD) primaries. CVs and other accreting WD binaries (AWBs) are useful laboratories for studying accretion flows, gas dynamics, outflows, transient outbursts, and explosive…

High Energy Astrophysical Phenomena · Physics 2020-07-23 Solen Balman

We present results from the first global 3D MHD simulations of accretion disks in Cataclysmic Variable (CV) systems in order to investigate the relative importance of angular momentum transport via turbulence driven by the magnetorotational…

Solar and Stellar Astrophysics · Physics 2016-06-01 Wenhua Ju , James M. Stone , Zhaohuan Zhu

Both continuum and emission line flickering are phenomena directly associated with the mass accretion process. In this work we simulate accretion disk Doppler maps including the effects of winds and flickering flares. Synthetic flickering…

Astrophysics · Physics 2015-05-13 Fabiola M. A. Ribeiro , Marcos P. Diaz

We examine published observations of dwarf nova oscillations (DNOs) on the rise and decline of outbursts and show that their rates of change are in reasonable agreement with those predicted from the magnetic accretion model. We find…

Astrophysics · Physics 2009-11-13 Brian Warner , Magaretha L. Pretorius

Emission line Doppler tomography is a powerful tool that resolves the accretion flow in binaries on micro-arcsecond scales using time-resolved spectroscopy. I present an extension to Doppler tomography that relaxes one of its fundamental…

Astrophysics · Physics 2009-11-07 D. Steeghs

The history of hydrodynamic numerical simulations for accretion disks in close binary systems is reviewed, in which emphasis is placed, in particular, on the facts that spiral shock waves were numerically found in 1986 by researchers…

We present multi-epoch, time-resolved optical spectroscopic observations of the dwarf nova HT Cas, obtained during 1986, 1992, 1995 and 2005 with the aim to study the properties of emission structures in the system. We determined that the…

Solar and Stellar Astrophysics · Physics 2016-01-20 V. V. Neustroev , S. V. Zharikov , N. V. Borisov

In response to our recent discovery of spiral arms in the accretion disc of IP Peg during rise to outburst, we have obtained time-resolved spectrophotometry of IP Peg during outburst maximum. In particular, indirect imaging of HeII 4686,…

Astrophysics · Physics 2009-10-31 E. T. Harlaftis , D. Steeghs , K. Horne , E. Martin , A. Magazzu

We perform simulations in order to reveal the effect of observational and physical parameters on the reconstruction of a spiral structure in an accretion disk, using eclipse mapping techniques. We show that a model spiral structure is…

Astrophysics · Physics 2009-11-10 E. T. Harlaftis , R. Baptista , L. Morales-Rueda , T. R. Marsh , D. Steeghs

Circumstellar asymmetries such as central warps have recently been shown to cast shadows on outer disks. We investigate the hydrodynamical consequences of such variable illumination on the outer regions of a transition disk, and the…

Earth and Planetary Astrophysics · Physics 2016-05-17 Matias Montesinos , Sebastian Perez , Simon Casassus , Sebastian Marino , Jorge Cuadra , Valentin Christiaens

We have used a model of magnetic accretion to investigate the accretion flows of magnetic cataclysmic variables. Numerical simulations demonstrate that four types of flow are possible: discs, streams, rings and propellers. The fundamental…

Astrophysics · Physics 2009-11-13 A. J. Norton , O. W. Butters , T. L. Parker , G. A. Wynn

We present the results of qualitative consideration of possible changes occurring during the transition from the hot accretion disc to the cool one. We argue the possible existence of one more type of spiral density waves in the inner part…

Astrophysics · Physics 2009-11-10 D. V. Bisikalo , A. A. Boyarchuk , P. V. Kaygorodov , O. A. Kuznetsov , T. Matsuda

Spiral shocks in cataclysmic variables (CVs) are the result of tidal interactions of the mass donor star with the accretion disc. Their study is fundamental for our understanding of angular momentum transfer in discs. In our quest to learn…

Astrophysics · Physics 2007-05-23 L. Morales-Rueda , T. R. Marsh

Circumplanetary disks (CPDs) control the growth of planets, supply material for satellites to form, and provide observational signatures of young forming planets. We have carried out two dimensional hydrodynamical simulations with radiative…

Earth and Planetary Astrophysics · Physics 2016-12-20 Zhaohuan Zhu , Wenhua Ju , James M. Stone

The spiral arms spanning disk galaxies are believed to be created by density waves that propagate through galactic disks. We present a novel method of finding the co-rotation radius where the spiral arm pattern speed matches the velocities…

We obtained photometric observations of the nova-like cataclysmic variable RW Tri and gathered all available AAVSO and other data from the literature. We determined the system parameters and found their uncertainties using the code…

Solar and Stellar Astrophysics · Physics 2020-07-29 G. Subebekova , S. Zharikov , G. Tovmassian , V. Neustroev , M. Wolf , M. -S. Hernandez , H. Kucakova , S. Khokhlov

V341 Ara was recently recognised as one of the closest (d ~ 150 pc) and brightest (V~ 10) nova-like cataclysmic variables. This unique system is surrounded by a bright emission nebula, likely to be the remnant of a recent nova eruption.…

In this paper we discuss the influence of gravitational instabilities in massive protostellar discs on the dynamics of dust grains. Starting from a Smoothed Particle Hydrodynamics (SPH) simulation, we have computed the evolution of the dust…

Solar and Stellar Astrophysics · Physics 2015-08-06 Giovanni Dipierro , Paola Pinilla , Giuseppe Lodato , Leonardo Testi

We present synthetic Doppler maps of gaseous flows in binary IP Peg based on the results of 3D gasdynamical simulations. Using of gasdynamical calculations alongside with the Doppler tomography technique permits us to identify the main…