Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Three-dimensional observations of gyrating ion distributions far upstream from the Earth's bow shock and their association with low-frequency waves
Autore:
Meziane, K; Mazelle, C; Lin, RP; LeQueau, D; Larson, DE; Parks, GK; Lepping, RP;
Indirizzi:
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA Univ Calif Berkeley Berkeley CA USA 94720 Sci Lab, Berkeley, CA 94720 USA Ctr Etud Spatiale Rayonnements, F-31029 Toulouse, France Ctr Etud SpatialeRayonnements Toulouse France F-31029 Toulouse, France Univ Washington, Geophys Program, Seattle, WA 98195 USA Univ Washington Seattle WA USA 98195 ophys Program, Seattle, WA 98195 USA NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA NASA Greenbelt MD USA 20771 , Extraterr Phys Lab, Greenbelt, MD 20771 USA
Titolo Testata:
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
fascicolo: A4, volume: 106, anno: 2001,
pagine: 5731 - 5742
SICI:
0148-0227(20010401)106:A4<5731:TOOGID>2.0.ZU;2-8
Fonte:
ISI
Lingua:
ENG
Soggetto:
GYROPHASE-BUNCHED IONS; SOLAR-WIND; DIFFUSE IONS; ISEE-2 OBSERVATIONS; REFLECTED IONS; INSTABILITIES; POPULATIONS; PLASMA; INTERMEDIATE; SIMULATIONS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
35
Recensione:
Indirizzi per estratti:
Indirizzo: Meziane, K Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA UnivCalif Berkeley Berkeley CA USA 94720 rkeley, CA 94720 USA
Citazione:
K. Meziane et al., "Three-dimensional observations of gyrating ion distributions far upstream from the Earth's bow shock and their association with low-frequency waves", J GEO R-S P, 106(A4), 2001, pp. 5731-5742

Abstract

This report discusses the nature of gyrating ion distributions observed onboard the Wind spacecraft by the three-dimensional ion electrostatic analyzer with high geometrical factor (3DP PESA-High). The gyrating ion distributions are observed near the inner ion beam foreshock boundary at distances between similar to9 and similar to 83 R-E Our upstream measurements confirmseveral features previously reported using two-dimensional measurements. These distributions are observed in association with low-frequency waves with substantial amplitude (\ deltaB \ /B > 0.2). The analysis of the waves shows that they propagate in the right-hand mode roughly along the backgroundmagnetic field. The ions are bunched in gyrophase angle when the associated waves are quasi-monochromatic and high in amplitude. The peak of the ion distribution function rotates in the gyrophase plane. If the wave train is nonmonochromatic, the particle phase angle distribution is extended over a larger range, suggesting the occurrence of a phase mixing effect or a source at the shock. The phase angle distribution also seems to be energy-dependent, and no,gyrophase rotation is observed in this case. Furthermore, we have characterized the ion distributions by computing their densities as wellas parallel and perpendicular velocities. The results clearly indicate that the waves are cyclotron-resonant with the field-aligned beams observed just upstream. The resonance condition strongly suggests the local productionof these gyrating ions in a field-aligned-beam disruption. Such a resonantwave-particle interaction may be a dominant characteristic of the back-streaming ion population in the foreshock at large distances from the Earth's bow shock.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 01/06/20 alle ore 00:25:56