摘要:

It is shown that hydromagnetic waves, through the action of radiation pressure, can prevent the tail of the magnetosphere from closing near the earth. It is argued that the tail of the magnetosphere may be 20 to 50 AU long. The tail can close at such heliocentric distances in the charge‐exchange boundary shell where the solar wind is terminated and ionatom collisions are relatively frequen

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03913

年代:1964

数据来源: WILEY

摘要:

A dipole magnetic field is analytically compressed and extended to represent a possible effect of the solar wind on the earth's magnetic field on the day and night side of the earth in the earth‐sun meridian plane. The first and second adiabatic invariants of particle motion are used to calculate the mirror points of constant energy particles in the compressed and extended fields. The results support and clarify work by previous investigators, showing that shifts in mirror points of particles moving from one field to the other are large at large distances and smaller at lower altitudes. The results are compared to the experimental findings of recent satellites. It is concluded that field distortion may be a major cause of the observed shift in mirror points, but that final resolution of the problem will depend on further determination of the magnetic field on the night side of the eart

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03919

年代:1964

数据来源: WILEY

摘要:

Calculations on time dependence of the inner Van Allen belt proton population show that large changes of the population up to a factor of 50 will take place during the solar cycle. The effect is most pronounced for the region ofB‐Lspace corresponding to minimum altitudes of 300–700 km. Because protons of different energies respond to the changing solar cycle at different rates, the proton energy spectrums will change with time a

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03927

年代:1964

数据来源: WILEY

摘要:

A counter telescope, composed of nine AuSi solid‐state detectors for measuring the energy loss and range of vertically incident particles, was carried into a polar orbit by an oriented satellite on December 12, 1961. The choice of detectors and absorbers allowed separation of protons and α particles with energies between 10 and 250 Mev/nucleon. Although the quantity of data was limited by the failure of the vehicle transmitter, both the observed 85‐ to 130‐Mev proton flux and the α‐particle flux are consistent with other 1961 observations. In addition, a proton flux of ∼1 m−2sec−1ster−1Mev−1was measured in the energy range 10–85 Mev, indicating that the quiet time spectrum was much ‘flatter’ than theE−2spectrum that others have

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03939

年代:1964

数据来源: WILEY

摘要:

The time dependence of the flux of geomagnetically trapped electrons resulting from the July 9, 1962, high altitude nuclear explosion has been calculated assuming that the only forces perturbing the trapped electrons were collisions with atmospheric constituents. These theoretical results are compared with experimental data obtained with satellites Injun 1, Injun 3, and Explorer 15. AtL= 1.185 andL= 1.25, whereLis Mcllwain's magnetic shell parameter, there is good agreement between theory and experiment. At higherLvalues, however, the observed time changes were more rapid than those predicted by the atmospheric scattering theory. It is concluded that during the latter part of 1962 and the early part of 1963 the chief mechanism for removing electrons trapped in the regionL˜1.2

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03947

年代:1964

数据来源: WILEY

摘要:

In a series of high‐altitude cosmic ray intensity measurements, the technique of constant level flights with small extensible balloons was used. A reliable valve‐controlled system to level neoprene balloons with payloads of several kilograms at atmospheric depths between 4 and 10 g/cm2was developed. The detector system consisted of a double coincidence GM counter telescope unit with telemetry of single counting rates, coincidence rate, atmospheric pressure, and internal temperature. Total payload weight was only 1500 grams. Thirty‐seven balloon flights were made during the last two years to study the cosmic ray intensity at high altitudes and low altitudes. A computing method was developed to fit a function of the typeC(x,pλ) =Aexp (−x/L) ‐Bexp (−x/l) to the counting rate versus atmospheric depth curve for each flight. This fit turned out to be excellent, leading to comprehensive information on the cosmic ray absorption, condensed into only three cutoff dependent parametersA,B, andL, and a constant parameterl.Lrepresents the absorption length of the ionizing component; its mean value at 11.4‐gv geomagnetic cutoff rigidity was found to be 158 g/cm2. The parameterl, representing the apparent mean collision length, has a value of 86 g/cm2. This method provides a statistically accurate way to determine the extrapolated counting rate at the top of the atmosphere, given by the differenceCo=A‐B. The correlation of the calculated counting rates at Pfotzer maximum and at the top of the atmosphere with the Mina Aguilar neutron monitor rate is analyzed for a period of 18 months of decreasing solar activity. A gradual softening of the primary spectrum during the eleven‐year cycle re

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03959

年代:1964

数据来源: WILEY

摘要:

Data relating to the detection of solar protons in the neighborhood of the earth (1952–1963) and to neutron counts (1958–1963) have been distributed on the basis of the mean synodic solar rotation period, 27.3 days, and the approximate synodic month, 29.5 days. In the latter, apparent departures from random distribution are especially marked. At the present time it is not clear whether the 29.5‐day ‘effect’ is related to the sun or the moon or is only a statistical

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03965

年代:1964

数据来源: WILEY

摘要:

The geomagnetic daily planetary indices from 1932 to 1961, and also the starting days of great magnetic storms from 1840 to 1954, are examined for possible dependence on lunar phase. It is concluded, in agreement with Bartels but contrary to the findings of Bigg, that there is no evidence of any such dependence.

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03973

年代:1964

数据来源: WILEY

摘要:

Christchurch hourly meteor rates for one year were studied statistically for a possible lunar influence, both monthly and daily, by the method of harmonic dials. It is concluded, in agreement with Ellyett but contrary to the findings of Bowen, that there is no evidence of a lunar monthly variation nor of a lunar daily variation.

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03981

年代:1964

数据来源: WILEY

摘要:

Study of whistler mode signals from the station NPG at Seattle operating on 18.6 kc/s reveals that the received frequency of these signals can depart from the nominal frequency by as much as ±1 part in 105. The average frequency shift varies systematically during the course of a night, and it is possible that two modes, one more common than the other, are present, with frequency shifts of opposite signs. Signals have been recorded within 15 minutes having large frequency shifts of opposite sign. They are likely to have occurred simultaneously

ISSN:0148-0227    

DOI:10.1029/JZ069i019p03989

年代:1964

数据来源: WILEY