AMPLIFICATION OF COLLECTIVE MAGNETIC FLUCTUATIONS IN MAGNETIZED BI-MAXWELLIAN PLASMAS FOR PARALLEL WAVE VECTORS. I. ELECTRON-PROTON PLASMA
- The general electromagnetic fluctuation theory is a powerful tool to analyze the magnetic fluctuation spectrum of a plasma. Recent works utilizing this theory for a magnetized non-relativistic isotropic Maxwellian electron-proton plasma have demonstrated that the equilibrium ratio of vertical bar delta B vertical bar/B-0 can be as high as 10(-12). This value results from the balance between spontaneous emission of fluctuations and their damping, and it is considerably smaller than the observed value vertical bar delta B vertical bar/B-0 in the solar wind at 1 au, where 10(-3) less than or similar to vertical bar delta B vertical bar/B-0 less than or similar to 10(-1). In the present manuscript, we consider an anisotropic bi-Maxwellian distribution function to investigate the effect of plasma instabilities on the magnetic field fluctuations. We demonstrate that these instabilities strongly amplify the magnetic field fluctuations and provide a sufficient mechanism to explain the observed value of vertical bar delta B vertical bar/B-0 inThe general electromagnetic fluctuation theory is a powerful tool to analyze the magnetic fluctuation spectrum of a plasma. Recent works utilizing this theory for a magnetized non-relativistic isotropic Maxwellian electron-proton plasma have demonstrated that the equilibrium ratio of vertical bar delta B vertical bar/B-0 can be as high as 10(-12). This value results from the balance between spontaneous emission of fluctuations and their damping, and it is considerably smaller than the observed value vertical bar delta B vertical bar/B-0 in the solar wind at 1 au, where 10(-3) less than or similar to vertical bar delta B vertical bar/B-0 less than or similar to 10(-1). In the present manuscript, we consider an anisotropic bi-Maxwellian distribution function to investigate the effect of plasma instabilities on the magnetic field fluctuations. We demonstrate that these instabilities strongly amplify the magnetic field fluctuations and provide a sufficient mechanism to explain the observed value of vertical bar delta B vertical bar/B-0 in the solar wind at 1 au.…
Verfasserangaben: | Sergei VafinORCiDGND, R. Schlickeiser, P. H. Yoon |
---|---|
DOI: | https://doi.org/10.3847/0004-637X/829/1/41 |
ISSN: | 0004-637X |
ISSN: | 1538-4357 |
Titel des übergeordneten Werks (Englisch): | The astrophysical journal : an international review of spectroscopy and astronomical physics |
Verlag: | IOP Publ. Ltd. |
Verlagsort: | Bristol |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2016 |
Erscheinungsjahr: | 2016 |
Datum der Freischaltung: | 22.03.2020 |
Freies Schlagwort / Tag: | instabilities; magnetic fields; solar wind; turbulence; waves |
Band: | 829 |
Seitenanzahl: | 8 |
Fördernde Institution: | Deutsche Forschungsgemeinschaft [Schl 201/31-1, Schl 21/32-1]; NSF [AGS1550566]; BK21 plus program through the National Research Foundation (NRF) - Ministry of Education of Korea; Ruhr University Research School |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
Peer Review: | Referiert |