Anisotropy Characteristics of Upstream Proton Events
Abstract
Results are presented of a detailed analysis of proton anisotropies observed during an upstream event when ISEE-3 was approximately 80 earth radii upstream from the earth, and close to the sun-earth radial. During the first part of the event, particles were observed streaming mainly from the direction of the earth along the magnetic field. Later in the event, the angular distributions broadened until towards the end of the event, approximately equal intensities were observed with pitch angles from 0 deg up to 120 deg, with essentially no particles with pitch angles close to 180 deg. (Here a 0 deg pitch angle particle is defined as a particle moving upstream along the magnetic field.) Large amplitude low-frequency waves were observed in the magnetic field at ISEE-3 whenever enhanced fluxes of 90 deg protons were observed. It is argued that the 90 deg protons are the result of pitch angle scattering of the upstream moving protons in the region between the bow shock and ISEE-3.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 1981
- Bibcode:
- 1981ICRC....3..483S
- Keywords:
-
- Anisotropy;
- Bow Waves;
- Interplanetary Medium;
- Proton Energy;
- Solar Protons;
- Angular Distribution;
- Cosmic Rays;
- Geomagnetism;
- Interplanetary Magnetic Fields;
- Particle Motion;
- Pitch (Inclination);
- Shock Wave Interaction;
- Upstream;
- Space Radiation;
- ANISOTROPY;
- BOW WAVES;
- INTERPLANETARY MEDIUM;
- PROTON ENERGY;
- SOLAR PROTONS;
- ANGULAR DISTRIBUTION;
- COSMIC RAYS;
- GEOMAGNETISM;
- INTERPLANETARY MAGNETIC FIELDS;
- PARTICLE MOTION;
- PITCH (INCLINATION);
- SHOCK WAVE INTERACTION;
- UPSTREAM