Equatorial modulation and north-south asymmetry of galactic cosmic rays due to the interplanetary magnetic field

Journal Article · Thu Sep 01 04:00:00 EDT 1977 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA082i025p03643· OSTI ID:7297925

Ely, J T.A.

Measurements of galactic cosmic rays made in 1967 on a low-altitude polar satellite exhibited two kinds of quasi-periodic variations which were synchronous with the changes in sector polarity of the interplanetary magnetic field (IMF). A modulation of 30% in the equatorial flux and a north-south asymmetry of roughly the same magnitude were observed. Both effects have been found in the records of surface neutron monitors. Relevance of the equatorial modulation to IMF structure is discussed briefly. It is suggested that the north-south asymmetry is due to intermittent connection between the IMF and GMF (geomagnetic field) and that magnetospheric trapping of charged particles takes place at those times. Evidence is presented that connection occurs on the dayside of the earth.

• Research Organization: Space Sciences Division, Geophysics Program, University of Washington, Seattle, Washington 98195
• OSTI ID: 7297925
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 82:25; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640101* -- Astrophysics & Cosmology-- Cosmic Radiation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ASYMMETRY
COSMIC RADIATION
COSMIC RAY DETECTION
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
GEOMAGNETIC FIELD
INTERPLANETARY MAGNETIC FIELDS
IONIZING RADIATIONS
LEPTONS
MAGNETIC FIELDS
MODULATION
NORTH-SOUTH ASYMMETRY
PRIMARY COSMIC RADIATION
RADIATION DETECTION
RADIATIONS
TRAPPED ELECTRONS