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Alfv\'en waves are known to be important carriers of magnetic energy that could play a role in coronal heating and/or solar wind acceleration. As these waves are efficient energy carriers, how they are dissipated still remains one of the…

Solar and Stellar Astrophysics · Physics 2025-07-22 Anmol Kumar , Thomas A. Howson , Paolo Pagano , Ineke De Moortel

We present a novel method to evaluate the Alfven speed and the magnetic field strength along the streamer plasma sheet in the outer corona. The method is based on recent observations of streamer waves, which are regarded as the fast kink…

Solar and Stellar Astrophysics · Physics 2015-05-20 Y. Chen , S. W. Feng , B. Li , H. Q. Song , L. D. Xia , X. L. Kong , Xing Li

We use 2.5-D electromagnetic particle-in-cell simulation code to investigate the acceleration of electrons in solar coronal holes through the interaction of Alfv\'en waves with an interplume region. The interplume is modeled by a cavity…

Space Physics · Physics 2019-04-30 Khalil Daiffallah , Fabrice Mottez

We investigate the effects of heating generated by damping of Alfven waves on protostellar accretion disks. Two mechanisms of damping are investigated, nonlinear and turbulent, which were previously studied in stellar winds (Jatenco-Pereira…

Astrophysics · Physics 2009-10-31 M. J. Vasconcelos , V. Jatenco-Pereira , R. Opher

We present a parameter study of simulations of fragmentation regulated by gravity, magnetic fields, ambipolar diffusion, and nonlinear flows. The thin-sheet approximation is employed with periodic lateral boundary conditions, and the…

Astrophysics · Physics 2011-12-20 Shantanu Basu , Glenn E. Ciolek , Wolf Dapp , James Wurster

Complete asymptotic expansions are developed for slow, Alfv\'en and fast magnetohydrodynamic waves at the base of an isothermal three-dimensional (3D) plane stratified atmosphere. Together with existing convergent Frobenius series solutions…

Solar and Stellar Astrophysics · Physics 2021-12-28 Paul S. Cally

We present the results of numerical experiments, in which we study how the asphericities induced by the growth of the standing accretion shock instability (SASI) produce the gravitational waveforms in the postbounce phase of core-collapse…

Astrophysics · Physics 2016-08-30 Kei Kotake , Naofumi Ohnishi , Shoichi Yamada

We investigate prestellar core formation and accretion based on three-dimensional hydrodynamic simulations. Our simulations represent local $\sim 1$pc regions within giant molecular clouds where a supersonic turbulent flow converges,…

Solar and Stellar Astrophysics · Physics 2015-06-10 Munan Gong , Eve C. Ostriker

We present an one-dimensional numerical study of Alfven waves propagating along a radial magnetic field. Neglecting losses, any spherical Alfven wave, no matter how small its initial amplitude is, becomes nonlinear at sufficiently large…

Astrophysics · Physics 2009-10-30 Ulf Torkelsson , G. Christopher Boynton

Collisionless regime kinetic models for coherent nonlinear Alfven wave dynamics are studied using fluid moment equations with an approximate closure anzatz. Resonant particle effects are modelled by incorporating an additional term…

Plasma Physics · Physics 2009-10-30 M. V. Medvedev , P. H. Diamond

In the Earth auroral zone, the electron acceleration by Alfv\'en waves is sometimes a precursor of the non-propagating acceleration structures. In order to investigate how Alfv\'en waves could generate non-propagating electric fields, a…

Earth and Planetary Astrophysics · Physics 2012-10-03 Fabrice Mottez

Counterpropagating Alfv\'en waves are ubiquitously observed in many astrophysical environments, such as a star surface and a planetary foreshock. We discuss an efficient particle acceleration mechanism in two counterpropagating circularly…

High Energy Astrophysical Phenomena · Physics 2023-04-06 S. Isayama , K. Takahashi , S. Matsukiyo , T. Sano

Here we investigate the contribution of surface Alfven wave damping to the heating of the solar wind in minima conditions. These waves are present in regions of strong inhomogeneities in density or magnetic field (e. g., the border between…

Solar and Stellar Astrophysics · Physics 2015-05-14 R. M. Evans , M. Opher , V. Jatenco-Pereira , T. I. Gombosi

We numerically investigate the excitation and temporal evolution of oscillations in a two-dimensional coronal arcade by including the three-dimensional propagation of perturbations. The time evolution of impulsively generated perturbations…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. Rial , I. Arregui , J. Terradas , R. Oliver , J. L. Ballester

Bearing in mind the application to the theory of core-collapse supernovae, we performed a global linear analysis on the stability of spherically symmetric accretion flows through a standing shock wave onto a proto neutron star. As…

Astrophysics · Physics 2008-11-26 Tatsuya Yamasaki , Shoichi Yamada

Hydrodynamical instabilities, such as the standing accretion-shock instability (SASI), play an essential role in the dynamics of core-collapse supernovae, with observable imprints in the neutrino and gravitational wave signals. Yet, the…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Laurie Walk , Thierry Foglizzo , Irene Tamborra

We show that a helical shear flow of a magnetized plasma may serve as an efficient amplifier of Alfven waves. We find that even when the flow is purely ejectional (i.e., when no rotation is present) Alfven waves are amplified through the…

Astrophysics · Physics 2009-11-07 Andria D. Rogava , Swadesh M. Mahajan , Gianluigi Bodo , Silvano Massaglia

By 2D hydrodynamic simulations including a detailed equation of state and neutrino transport, we investigate the interplay between different non-radial hydrodynamic instabilities that play a role during the postbounce accretion phase of…

Astrophysics · Physics 2009-06-23 L. Scheck , H. -Th. Janka , T. Foglizzo , K. Kifonidis

The parametric decay instability (PDI) of Alfven waves -- where a pump Alfven wave decays into a backward-propagating child Alfven wave and a forward ion acoustic wave -- is a fundamental nonlinear wave-wave interaction and holds…

Plasma Physics · Physics 2025-07-21 Feiyu Li , Seth Dorfman , Xiangrong Fu

This paper is devoted to the study of the gravitational instability of a medium permeated by a uniform magnetic field along which a circularly polarized Alfven wave propagates. We concentrate on the case of perturbations purely transverse…

Astrophysics · Physics 2009-11-07 Adriana Gazol , Thierry Passot