Reflection of the solar wind ions at the earth's bow shock: energization

Journal Article · Sat Oct 01 04:00:00 EDT 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA10p07853· OSTI ID:7051801

Bonifazi, C; Moreno, G; Russell, C T

The energies of the field-aligned proton beams observed upstream of the earth's bow shock are tested, on a statistical basis, against a simple reflection model. The comparison is carried out using both plasma and magnetic field data collected by the ISEE 2 spacecraft. The observations refer to the period from November 5 to December 20, 1977. According to this model, some of the solar wind protons incident upon the earth's shock front when reflected upstream gain energy by displacement parallel to the interplanetary electric field. The energy gained in the reflection can be described as a function of the angles between the interplanetary magnetic field, the solar wind bulk velocity, and the local shock normal. The task of finding these angles, i.e., the expected source point of the reflected ions at the earth's shock front, has been resolved using both the measured magnetic field direction and actual beam trajectory. The latter method, which takes into account the ion drift velocity, leads to a better agreement between theory and observations when far from the shock. In particular, it allows us to check the energies of the field-aligned beams even when they are observed far from the earth's bow shock (at distances up to 10-15 R/sub E/). We confirm, on a statistical basis, the test of the model recently carried out using the Los Alamos National Laboratory/Max-Planck-extraterrestrische observations on ISEE 1 and 2. We infer that reflected beams can sometimes propagate far upstream of the earth's bow shock without changing their energy properties.

• Research Organization: Space Science Department of European Space Agency/ESTEC
• OSTI ID: 7051801
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A10; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
BACKSCATTERING
BEAMS
EARTH ATMOSPHERE
ELECTRIC FIELDS
MAGNETOSPHERE
MATHEMATICS
NUCLEON BEAMS
PARTICLE BEAMS
PLASMA ACCELERATION
PROTON BEAMS
PROTON DENSITY
REFLECTION
SCATTERING
SOLAR ACTIVITY
SOLAR WIND
STATISTICS