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Related papers: Magnetic field generation in relativistic shocks

200 papers

We numerically investigate the process of generating magnetic fields from temperature anisotropy of electrons in collisionless initially uniform plasmas. We use a fully kinetic modeling and compare it against a hybrid modeling which treats…

Plasma Physics · Physics 2023-05-08 A. Sladkov , A. Korzhimanov

We have investigated particle acceleration and emission from shocks and shear flows associated with an unmagnetized relativistic jet plasma propagating into an unmagnetized ambient plasma. Strong electro-magnetic fields are generated in the…

High Energy Astrophysical Phenomena · Physics 2014-12-23 K. -I. Nishikawa , P. Hardee , I. Dutan , B. Zhang , A. Meli , E. J. Choi , K. Min , J. Niemiec , Y. Mizuno , M. Medvedev , A. Nordlund , J. T. Frederiksen , H. Sol , M. Pohl , D. Hartmann

We investigate the formation of plasma cavities in unmagnetized relativistic pair shocks and demonstrate that these cavities emerge naturally as a nonlinear consequence of asymmetric Weibel instability. We provide an intuitive physical…

High Energy Astrophysical Phenomena · Physics 2026-01-07 Ivan Demidov , Yuri Lyubarsky , Uri Keshet

We report on a first-principles numerical and theoretical study of plasma dynamo in a fully kinetic framework. By applying an external mechanical force to an initially unmagnetized plasma, we develop a self-consistent treatment of the…

High Energy Astrophysical Phenomena · Physics 2023-08-07 Muni Zhou , Vladimir Zhdankin , Matthew W. Kunz , Nuno F. Loureiro , Dmitri A. Uzdensky

The electron beam Weibel instability in the electrostatic collisionless shock is studied via particle in cell simulation. When the non-relativistic incoming plasmas collide with cold dilute plasmas, an electrostatic shock forms near the…

Plasma Physics · Physics 2022-02-10 Jiansheng Yao , Yingkui Zhao , Biyao Ouyang , Difa Ye

Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities) created in collisionless shocks are responsible for particle…

Astrophysics · Physics 2015-06-24 K. -I. Nishikawa , P. Hardee , C. B. Hededal , G. Richardson , R. Preece , H. Sol , G. J. Fishman

The dynamics of two counter-streaming electron-positron-ion unmagnetized plasma shells with zero net charge is analyzed in the context of magnetic field generation in GRB internal shocks due to the Weibel instability. The effects of large…

Astrophysics · Physics 2008-11-26 M. Fiore , L. O. Silva , C. Ren , M. A. Tzoufras , W. B. Mori

It is shown that collisionless shock waves can be driven in unmagnetized electron-positron plasmas by performing a two-dimensional particle-in-cell simulation. At the shock transition region, strong magnetic fields are generated by a…

Astrophysics · Physics 2008-03-31 Tsunehiko N. Kato

The origin of the micro-Gauss magnetic fields in galaxy clusters is one of the outstanding problem of modern cosmology. We have performed three-dimensional particle-in-cell simulations of the nonrelativistic Weibel instability in an…

Astrophysics · Physics 2009-11-11 Mikhail V. Medvedev , Luis O. Silva , Marc Kamionkowski

We study the long term evolution of magnetic fields generated by an initially unmagnetized collisionless relativistic $e^+e^-$ shock. Our 2D particle-in-cell numerical simulations show that downstream of such a Weibel-mediated shock,…

Astrophysics · Physics 2009-06-23 Philip Chang , Anatoly Spitkovsky , Jonathan Arons

The saturation mechanism of the Weibel instability is investigated theoretically by considering the evolution of currents in numerous cylindrical beams that are generated in the initial stage of the instability. Based on a physical model of…

Plasma Physics · Physics 2007-05-23 Tsunehiko N. Kato

It is generally accepted that magnetic fields generated in the nonlinear development of the transverse Weibel instability provide effective collisionality in unmagnetized collisionless shocks. Recently, extensive two and three dimensional…

Astrophysics · Physics 2009-11-13 Milos Milosavljevic , Ehud Nakar , Anatoly Spitkovsky

The time evolution and saturation of the Weibel instability at the ion Alfv\'en current are presented by ab initio particle-in-cell simulations. We found that the ion Weibel current in 3D could evolve into the Alfv\'en current where the…

High Energy Astrophysical Phenomena · Physics 2018-06-13 Makoto Takamoto , Yosuke Matsumoto , Tsunehiko N. Kato

The mechanisms that generate "seed" magnetic fields in our Universe and that amplify them throughout cosmic time remain poorly understood. By means of fully-kinetic particle-in-cell simulations of turbulent, initially unmagnetized plasmas,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 L. Sironi , L. Comisso , R. Golant

Plasma instabilities (e.g., Buneman, Weibel and other two-stream instabilities) created in collisionless shocks may be responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle…

Astrophysics · Physics 2009-11-13 K. -I. Nishikawa , P. E. Hardee , C. B. Hededal , G. J. Fishman

The onset and evolution of magnetic fields in laboratory and astrophysical plasmas is determined by several mechanisms, including instabilities, dynamo effects and ultra-high energy particle flows through gas, plasma and interstellar-media.…

Plasma Physics · Physics 2015-05-20 A. Flacco , J. Vieira , A. Lifschitz , F. Sylla , S. Kahaly , M. Veltcheva , L. O. Silva , V. Malka

The Weibel instability driven by two symmetric counter-streaming relativistic electron plasmas, also referred to as current-filamentation instability, is studied in a constant and uniform external magnetic field aligned with the plasma…

Plasma Physics · Physics 2017-02-08 A. Grassi , M. Grech , F. Amiranoff , F. Pegoraro , A. Macchi , C. Riconda

A two-dimensional electromagnetic particle-in-cell simulation with the realistic ion-to-electron mass ratio of 1836 is carried out to investigate the electrostatic collisionless shocks in relatively high-speed (~3000 km s^-1) plasma flows…

Plasma Physics · Physics 2010-05-12 Tsunehiko N. Kato , Hideaki Takabe

H-alpha emission from supernova remnants (SNRs) implies the existence of neutral hydrogen in the circumstellar medium. Some of the neutral particles penetrating the shock are ionized by the charge exchange process and make a cold ion beam…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Yutaka Ohira , Toshio Terasawa , Fumio Takahara

Afterglows of gamma-ray bursts are believed to require magnetic fields much stronger than that of the compressed pre-shock medium. As an alternative to microscopic plasma instabilities, we propose amplification of the field by macroscopic…

Astrophysics · Physics 2009-11-13 Lorenzo Sironi , Jeremy Goodman