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Title: A statistical study of EMIC waves observed by Cluster: 2. Associated plasma conditions

This is the second in a pair of papers discussing a statistical study of electromagnetic ion cyclotron (EMIC) waves detected during 10 years (2001–2010) of Cluster observations. In the first paper, an analysis of EMIC wave properties (i.e., wave power, polarization, normal angle, and wave propagation angle) is presented in both the magnetic latitude (MLAT)-distance as well as magnetic local time (MLT)-L frames. In addition, this paper focuses on the distribution of EMIC wave-associated plasma conditions as well as two EMIC wave generation proxies (the electron plasma frequency to gyrofrequency ratio proxy and the linear theory proxy) in these same frames. Based on the distributions of hot H + anisotropy, electron and hot H+ density measurements, hot H + parallel plasma beta, and the calculated wave generation proxies, three source regions of EMIC waves appear to exist: (1) the well-known overlap between cold plasmaspheric or plume populations with hot anisotropic ring current populations in the postnoon to dusk MLT region; (2) regions all along the dayside magnetosphere at high L shells related to dayside magnetospheric compression and drift shell splitting; and (3) off-equator regions possibly associated with the Shabansky orbits in the dayside magnetosphere.
 [1] ;  [2] ;  [2] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7]
  1. Univ. of New Hampshire, Durham, NH (United States); Southwest Research Institute, San Antonio, TX (United States); Univ. of Texas at San Antonio, San Antonio, TX (United States)
  2. Univ. of New Hampshire, Durham, NH (United States)
  3. Chinese Academy of Sciences, Beijing (China)
  4. Max-Plank-Institut fur Extraterrestrische Physik, Garching (Germany)
  5. Rutherford Appleton Laboratory, Didcot (United Kingdom)
  6. Swedish Institute of Space Physics (IRF), Uppsala (Sweden)
  7. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2169-9380
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Name: Journal of Geophysical Research. Space Physics; Journal ID: ISSN 2169-9380
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
National Aeronautic and Space Administration (NASA); USDOE
Country of Publication:
United States
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Heliospheric and Magnetospheric Physics
OSTI Identifier: