Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Controlling Factors of Chorus Spectral Gaps

Journal Article · · Journal of Geophysical Research. Space Physics
DOI:https://doi.org/10.1029/2023JA031893· OSTI ID:2448134
 [1];  [1];  [2];  [3];  [1];  [4];  [4];  [4];  [5];  [6];  [7];  [8];  [9]
  1. Department of Atmospheric and Oceanic Sciences University of California Los Angeles CA USA
  2. Center for Space Physics Boston University Boston MA USA
  3. Department of Atmospheric and Oceanic Sciences and Department of Earth, Planetary, and Space Sciences University of California Los Angeles CA USA
  4. Department of Physics and Astronomy University of Iowa Iowa City IA USA
  5. Space Science and Applications Group Los Alamos National Laboratory Los Alamos NM USA, Los Alamos National Laboratory Los Alamos NM USA
  6. The New Mexico Consortium Los Alamos NM USA
  7. Space Science Applications Laboratory The Aerospace Corporation El Segundo CA USA
  8. Institute for the Study of Earth, Oceans, and Space University of New Hampshire Durham NH USA
  9. Laboratory for Atmospheric and Space Physics University of Colorado Boulder CO USA
+ Show Author Affiliations

Abstract

The present study compares a single‐band chorus wave against a banded chorus wave observed by Van Allen Probes at adjacent times, and demonstrates that the single‐band chorus wave is associated with an anisotropic electron population over a broad energy range, while the banded chorus wave is accompanied by an electron phase space density plateau and an electron anisotropy reduction around Landau resonant energies. We further compare banded chorus waves with different spectral gap widths, and show that a wider spectral gap is associated with electron isotropization extending to higher energies with respect to the equatorial Landau resonant energy. We suggest that early generated chorus waves isotropize electrons via Landau resonant acceleration, and the waves that propagate to higher latitudes isotropize electrons at higher energies. The isotropization extending to higher energies leads to a larger spectral gap of new chorus waves after electrons bounce back to the equator.

Sponsoring Organization:
USDOE
Grant/Contract Number:
SC0010578
OSTI ID:
2448134
Journal Information:
Journal of Geophysical Research. Space Physics, Journal Name: Journal of Geophysical Research. Space Physics Journal Issue: 10 Vol. 129; ISSN 2169-9380
Publisher:
American Geophysical Union (AGU)Copyright Statement
Country of Publication:
United States
Language:
English

References (27)

Whistler anisotropy instabilities as the source of banded chorus: Van Allen Probes observations and particle-in-cell simulations: FU ET AL. journal October 2014
Study of EMIC wave excitation using direct ion measurements: MIN ET AL. journal April 2015
Generation of multiband chorus by lower band cascade in the Earth's magnetosphere journal March 2016
Poynting vector and wave vector directions of equatorial chorus: CHORUS POYNTING VECTOR journal December 2016
Self-consistent formation of a 0.5 cyclotron frequency gap in magnetospheric whistler mode waves: WHISTLER MODE FREQUENCY GAP FORMATION journal August 2017
Science Objectives and Rationale for the Radiation Belt Storm Probes Mission journal September 2012
Science Goals and Overview of the Radiation Belt Storm Probes (RBSP) Energetic Particle, Composition, and Thermal Plasma (ECT) Suite on NASA’s Van Allen Probes Mission journal October 2013
Helium, Oxygen, Proton, and Electron (HOPE) Mass Spectrometer for the Radiation Belt Storm Probes Mission journal March 2013
The Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) on RBSP journal June 2013
Introduction to Plasma Physics book January 2012
Spatio-temporal structure of storm-time chorus journal January 2003
Electron density in the magnetosphere journal January 2004
Landau damping and resultant unidirectional propagation of chorus waves journal January 2006
Observations of chorus at Saturn using the Cassini Radio and Plasma Wave Science instrument: OBSERVATIONS OF CHORUS AT SATURN journal December 2008
Nonlinear mechanisms of lower-band and upper-band VLF chorus emissions in the magnetosphere: NONLINEAR MECHANISMS OF CHORUS EMISSIONS journal July 2009
THEMIS analysis of observed equatorial electron distributions responsible for the chorus excitation: ELECTRON DISTRIBUTIONS FOR CHORUS WAVES journal June 2010
Generation of whistler mode emissions in the inner magnetosphere: An event study: GENERATION OF WHISTLER WAVES journal August 2010
Excitation of banded whistler waves in the magnetosphere: EXCITATION OF BANDED WHISTLERS journal July 2011
THEMIS observation of chorus elements without a gap at half the gyrofrequency: CONTINUOUS RISING TONE CHORUS journal November 2012
Statistical Results of the Power Gap Between Lower‐Band and Upper‐Band Chorus Waves journal April 2019
Typical Characteristics of Whistler Mode Waves Categorized by Their Spectral Properties Using Van Allen Probes Observations journal April 2019
Parallel Acceleration of Suprathermal Electrons Caused by Whistler‐Mode Hiss Waves journal November 2019
Detection of Jovian whistler mode chorus; Implications for the Io torus aurora journal January 1980
Banded chorus-A new type of VLF radiation observed in the magnetosphere by OGO 1 and OGO 3 journal June 1969
Use of the three-dimensional covariance matrix in analyzing the polarization properties of plane waves journal October 1972
Postmidnight chorus: A substorm phenomenon journal January 1974
Low-Frequency Whistler Mode journal January 1966

Similar Records

Unraveling the Formation Region and Frequency of Chorus Spectral Gaps
Journal Article · Thu Sep 29 00:00:00 EDT 2022 · Geophysical Research Letters · OSTI ID:1996042
Origin of two-band chorus in the radiation belt of Earth
Journal Article · Mon Oct 14 00:00:00 EDT 2019 · Nature Communications · OSTI ID:1624199

Related Subjects