ON THE UNUSUAL INCREASE OF COSMIC-RAY INTENSITY OF FEBRUARY 23, 1956

Technical Report · Sat Oct 31 04:00:00 EST 1959

OSTI ID:4258767

Kitamura, M

The data of cosmic-ray intensity observed over the world were used to study the unusual increase of cosmic-ray intensity which was connected with a solar flare on February 22, 1956, and to investigate the propagation process of solar cosmic-ray particles through interplanetary space. The decline of particle intensity as a function of time, except for high-energy particles, is favorable to the diffusion mechanism of solar cosmic-ray particles through the interplanetary space from the source to the earth, and the latitade de pendence of the time at which maximum intensity of solar cosmic-ray in American zone took place confirms the diffusion mecbanism of the pnsticles. Also, a clear distinction is found between,the time of onset of cosmicray increase in German- Soviet zone and American zone. That is, the particle intensity increased more promptly in the German-Soviet zone than in American zone in high latitudes. It is shown thrt the particles arriving at the former region promptly were transmitted straight from the source which is in the inner solar system of magnetic field-free cavity and affected by the geomagnetic field in the vicinity of the earth, while the particles arriving at the latter region were propagated through interplanetary space by a diffusion mechanism. Radius of the particle source is inferred to be 0.8 to 0.9 A. U., judging from the width of prompt onset region on the earth in conjunction with the calculation of the impact zone by R. Lust. Observed facts and theoretical considerations lead to a model in which the inner solar system is a magnetic field-free cavity of radius 0.8 to 0.9 A. U. enclosed by magnetic gas clouds, through which the solar cosmic-ray parrticles are diffused and reach the interstellar space. It is concluded considering the diffusion process of the particles through interplanetary space, that the integral energy spectum of solar cosmic-ray particles is proportional to E-5 instead of E-7 proposed by J. A. Simpson and others. (auth)

• Research Organization: Meteorological Research Inst., Tokyo
• NSA Number: NSA-13-006924
• OSTI ID: 4258767
• Report Number(s): A/CONF.15/P/1966
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

COSMIC RADIATION
DIFFUSION
EARTH
GASES
MAGNETIC FIELDS
PARTICLE SOURCES
PHYSICS AND MATHEMATICS
SPACE
SPECTRA
SUN
VARIATIONS