S. N. Vernov

Radiation belts in the region of the South-Atlantic magnetic anomaly

ConclusionThe difference of the geomagnetic field from the field of the idealized dipole not only creates certain difficulties for studying the geomagnetically trapped radiation but also presents new possibilities for studying the processes which control the particle movement in the magnetosphere. It will be remembered that the fact that the geomagnetic field is not a dipole played a decisive role in the very beginning of the formation of our ideas about the nature of the intense fluxes of the penetrating radiation detected during the satellite flights.In fact, the longitude dependence of the lower boundary of the penetrating radiation in the region of low latitudes according to the properties of the geomagnetic field made it possible to conclude immediately that the detected radiation was caused by the geomagnetically trapped particles.As to the difficulties in the trapped radiation study caused by the existence of the anomalies, they, first of all, result in the original and, at the first glance, incomprehensible form of the particle intensity contours drawn in geographical coordinates for low altitudes. However, when turning to the McIlwain coordinate system, which is naturally connected with the real magnetic field, the seeming chaos in the radiation distribution disappears being unexpectedly replaced by harmony and order. But even in this coordinate system some ambiguities are observed connected with the distortion of the adiabatic invariants during the time comparable with the period of the particle drift around the earth.The thorough analysis of these effects in combination with the observations of the radiation at high altitudes may answer such a principle question as the question about the velocity of the movements of the mirror points.It should be noted that some information has been obtained to date on the movement of the electron-mirror points only and similar information about protons is absent.It is possible that new aspects of the use of the magnetic anomalies for studying the geomagnetosphere will appear in due time.

Propagation of Solar and Galactic Cosmic Rays of Low Energies in Interplanetary Medium

The report summarizes the results of measurements of low-energy cosmic rays from Zond-3, Venus-2, Venus-3, and Venus-4 space probes for the period from 1965 to 1967 as well as preliminary results from Venus-5 and Venus-6 space probes. It has been shown on the basis of solar cosmic ray bursts and Forbush-decreases of galactic cosmic rays that the solar cosmic rays propagate rapidly from the ejection region near the sun along the beam of magnetic lines of force emerging from the active region on the sun and slowly when they are retarded in the region of the field knee created by the shock wave from the burst and move together with the knee at the velocity of the wave. It has been shown that the observed retardation of shock waves from the bursts results in disappearance of Forbush-decreases and accumulation of solar cosmic rays at distances of ~ 2 AU from the sun. It has been shown on the basis of the observations of variations in galactic cosmic rays that the variation parameters (amplitude, steepness of the fall) are determined by the dynamics, latitude, and development phase of active regions.

Study of the cosmic-ray soft component by the 3rd Soviet earth satellite

Abstract Measurements made with a scintillation counter installed on the 3rd Soviet earth satellite are presented. By this instrument the counting rate corresponding to the energy greater than 35 keV and the total ionization in the scintillator were measured. Two zones of high intensity radiation are observed. The first one is observed on latitudes greater than 60° and altitudes above 300 km. Radiation in this “polar zone” consists of electrons of energy about 100 keV and flux rate of 103 to 104 particles/cm2 sec sterad (increasing with altitude). The second zone is observed on altitudes about 1000 km and latitudes not exceeding 50°. In this “equator zone” the ionization in the scintillator is 3 orders of magnitude greater than that due to cosmic-rays. Strong dependence on latitude and longitude is assumed to be consistent with the symmetry of the zone relative to the inclined and displaced geomagnetic axis. Lower limits are given for the γ-radiation from the Sun.

The outer radiation belt of the earth at the altitude of 320 km

Scintillation and gas-discharge counters on the second Soviet spaceship allowed a detailed investigation of the outer radiation belt near the earth and established its boundaries in relation to longitude. The spaceship orbit was almost circular at an altitude of 306 to 339 km. The energy threshold of the counter channel was 25 kev. (W,D.M.)

Solar Cosmic Ray Increase on 25 February – 5 March, 1969 According to Measurements from Venus-5 and Venus-6 Space Probes

During the period from 25 Feb. to 5 March, 1969 the Venus-5 and Venus-6 space probes detected an increase in solar cosmic ray protons with E p > 1 MeV and electrons with E e > 0.05 MeV. The increase had a complex form and was due to a series of solar flares occurring in a single active region. The main flares occurred on 24 and 27 Feb. 1969. A scheme for the development of a disturbance in the interplanetary medium caused by the above mentioned flares is considered on the basis of the analysis of the form of increase for various proton energies, anisotropy of protons with E p = 1 ÷ 4 MeV, and the increase in electrons with E e > 0.05 MeV together with solar and geophysical events.

Investigation of the radiation belts in the region of the Brazilian magnetic anomaly

Abstract The geographical distribution of the radiation intensity in the region of the Brazilian magnetic anomaly is given according to the data of the “Kosmos-7” and “Kosmos-15” satellites. The distribution obtained is compared with the results of measurements by the “Kosmos-3” and “Kosmos-5” (4) satellites and the “Discoverer-31” satellite (3,5) .

The earth's radiation belts at altitudes of 180–250 km

The third Soviet satellite in an orbit with perigee 187 km, apogee 265 km, and inclination to the equatorial plane of 65 deg , made it possible to trace the variation in the intensity and geographical position of the radiation belts on transition to lower altitudes. The satellites passage through sections of the radiation belts was accompanied by a sharp rise in the counting rate. Points were plotted on a map, at which the counting rate greatly exceeded the cosmic background. For comparison, points obtained from the second Soviet satellite were also plotted. Conjugate points were found for some points in the Northern and Southern Hemispheres. The unambiguous association between the zones of increased intensity in the Northern and Southern Hemispheres was one of the proofs that these zones belong to the outer radiation belt. (C.E.S.)

Investigation of the van allen belts in the region of the brazilian magnetic anomaly at altitudes of 235–345 km

Abstract The results are reported of an investigation of the Van Allen belts in the region of the Brazilian magnetic anomaly by Geiger and scintillation counters in the satellites “Kosmos-4”, “Kosmos-7”, “Kosmos-9” and “Kosmos-15”. A comparison is made between the results obtained in these satellites and the 2nd space vehicle.

STUDY OF RADIATIONS DURING THE FLIGHTS OF INTERPLANETARY AUTOMATIC STATIONS MARS-1 AND LUNA-4

Abstract A brief description is given of the apparatus in the “Mars-1” and “Luna-4” stations for recording radiations and the results obtained are discussed. It is found that up to a distance of 0.24 astronomical units from the Earth the intensity of the cosmic radiation remains practically the same. Data are also given on the cosmic ray intensity at different periods of the solar activity cycle. During the flight of “Luna-4” slow smooth variations in the cosmic ray intensity were recorded; these are connected with the variation of the magnetic state of the Solar System. During its flight away from the Earth “Mars-1” passed through the Van Allen belts and data are given on these.