Quasiperiodic Whistler Mode Emissions Observed by the Van Allen Probes Spacecraft

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F18%3A00506364" target="_blank" >RIV/68378289:_____/18:00506364 - isvavai.cz</a>

Result on the web

<a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JA026058" target="_blank" >https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JA026058</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2018JA026058" target="_blank" >10.1029/2018JA026058</a>

Result language

angličtina

Original language name

Quasiperiodic Whistler Mode Emissions Observed by the Van Allen Probes Spacecraft

Original language description

Quasiperiodic (QP) emissions are whistler mode electromagnetic waves observed in the inner magnetosphere that exhibit a QP time modulation of the wave intensity. We analyze 768 QP events observed during the first 5 years of the operation of the Van Allen Probes spacecraft (September 2012 to October 2017). Multicomponent wave measurements performed in the equatorial region, where the emissions are likely generated, are used to reveal new experimental information about their properties. We show that the events are observed nearly exclusively inside the plasmasphere. Wave frequencies are mostly between about 0.5 and 4 kHz. The events observed at larger radial distances and on the duskside tend to have slightly lower frequencies than the emissions observed elsewhere. The maximum event frequencies are limited by half of the equatorial electron gyrofrequency, suggesting the importance of wave ducting. Modulation periods are typically between about 0.5 and 5 min, and they increase with the in situ measured plasma number density. This increase is consistent with the main mechanisms suggested to explain the origin of the QP modulation. Two-point measurements performed by the Van Allen Probes are used to estimate a typical spatial extent of the emissions to about 1 R-E in radial distance and 1.5 hr in magnetic local time. Detailed wave analysis shows that the emissions are right-hand circularly polarized, and they usually come from several different directions simultaneously. They, however, predominantly propagate at rather low wave normal angles and away from the geomagnetic equator.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10305 - Fluids and plasma physics (including surface physics)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geophysical Research: Space Physics

ISSN

2169-9380

e-ISSN

—

Volume of the periodical

123

Issue of the periodical within the volume

11

Country of publishing house

US - UNITED STATES

Number of pages

14

Pages from-to

8969-8982

UT code for WoS article

000453227400006

EID of the result in the Scopus database

2-s2.0-85055951159