Počet záznamů: 1
Direct Measurement of Low‐Energy Electron Foreshock Beams
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SYSNO ASEP 0510734 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Direct Measurement of Low‐Energy Electron Foreshock Beams Tvůrce(i) Souček, Jan (UFA-U) RID, ORCID
Píša, David (UFA-U) RID, ORCID
Santolík, Ondřej (UFA-U) RID, ORCIDCelkový počet autorů 3 Zdroj.dok. Journal of Geophysical Research-Space Physics. - : Wiley - ISSN 2169-9380
Roč. 124, č. 4 (2019), s. 2380-2392Poč.str. 13 s. Forma vydání Tištěná - P Jazyk dok. eng - angličtina Země vyd. US - Spojené státy americké Klíč. slova plasma waves upstream ; high-frequency waves ; ion-sound-waves ; Langmuir-waves ; solar-wind ; nonthermal electrons ; decay ; oscillations ; mode Vědní obor RIV BL - Fyzika plazmatu a výboje v plynech Obor OECD Fluids and plasma physics (including surface physics) CEP GA17-08772S GA ČR - Grantová agentura ČR GJ16-16050Y GA ČR - Grantová agentura ČR Způsob publikování Omezený přístup Institucionální podpora UFA-U - RVO:68378289 UT WOS 000477707800002 EID SCOPUS 85064175144 DOI 10.1029/2019JA026470 Anotace Electrostatic plasma waves above and below the local electron plasma frequency represent a characteristic feature of the foreshock region. These waves are known to be generated by electron beams originating from the bow shock and their spectrum varies from narrowband intense waves close to foreshock edge to weaker broadband emissions further downstream. We present a statistical analysis of electron beams observed in the terrestrial foreshock by the Cluster spacecraft. We compared the energy of foreshock electron beams with the spectrum of electrostatic waves and established a clear correspondence between beam energy and spectrum of the waves. The broadband emissions are correlated with low-energy beams, while high-energy electron beams are associated with narrowband Langmuir waves. Next we solved the linear dispersion relation for a subset of observed electron plasma distributions. We discovered that while the observed electron distributions often exhibit a 'bump on tail' feature necessary for an instability, the observed combination of beam energy, density, and temperature typically corresponds to a stable situation. This indicates that strongly unstable electron beams are quickly dissipated by the quasi-linear processes and only stable or marginally stable beams persist long enough to be observed by the instrument. Pracoviště Ústav fyziky atmosféry Kontakt Kateřina Adamovičová, adamovicova@ufa.cas.cz, Tel.: 272 016 012 ; Kateřina Potužníková, kaca@ufa.cas.cz, Tel.: 272 016 019 Rok sběru 2020 Elektronická adresa https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2019JA026470
Počet záznamů: 1