Recovery phase of galactic cosmic ray modulation in the outer heliosphere

Journal Article · Fri Aug 01 04:00:00 EDT 1986 · Geophys. Res. Lett.; (United States)

DOI:https://doi.org/10.1029/GL013i008p00785· OSTI ID:5111463

McDonald, F B; von Rosenvinge, T T; Lal, N; Trainor, J H; Schuster, P

Energetic hydrogen and helium nuclei from the galaxy (cosmic rays) enter the solar system with varying degrees of difficulty during the 11-year solar magnetic cycle, resulting in spatial and temporal variations of particle intensities in the heliosphere. We report observations of these variations from the ISEE-3, Voyager 1 and 2, and Pioneer 10 spacecraft during the period from early 1981 to early 1986 and for heliocentric distances ranging from 1 to 37 AU. During this time the high energy intensities in the outer heliosphere have been increasing exponentially at a rate of approximately 20%/year with occasional interruptions due to enhanced solar activity. There are long delays (--3 years) in the recovery of the intensity of low energy particles relative to high energy particles that significantly alter the energy spectra. The radial intensity gradients measured in the ecliptic plane are observed to remain constant or to decrease at the time of the reversal of the solar magnetic poles in 1980.

• Research Organization: NASA Headquarters
• OSTI ID: 5111463
• Journal Information: Geophys. Res. Lett.; (United States), Journal Name: Geophys. Res. Lett.; (United States) Vol. 13:8; ISSN GPRLA
• Country of Publication: United States
• Language: English

Related Subjects

640101* -- Astrophysics & Cosmology-- Cosmic Radiation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC NUCLEI
COSMIC RADIATION
ELEMENTS
ENERGY LEVELS
ENERGY SPECTRA
FLUIDS
GASES
HELIUM
HYDROGEN
IONIZING RADIATIONS
NONMETALS
NUCLEI
RADIATIONS
RARE GASES
SOLAR ACTIVITY
SOLAR PARTICLES
SOLAR RADIATION
SPACE VEHICLES
SPECTRA
STELLAR RADIATION
VARIATIONS
VEHICLES
VOYAGER SPACE PROBES