Two anisotropies of the cosmic-ray particles producing the cosmic-ray diurnal variation

1968 ◽  
Vol 46 (10) ◽  
pp. S828-S830
Author(s):  
Masatoshi Kitamura
Keyword(s):  
Cosmic Rays ◽  
Diurnal Variation ◽  
Interplanetary Space ◽  
Geomagnetic Latitude ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Low Energy ◽  
The Other ◽  
Energy Spectra ◽  
Cosmic Ray Intensity

The solar diurnal variations of both meson and nucleon components of cosmic rays at sea level at geomagnetic latitude 57.5° and geomagnetic longitude 0° are analyzed by the model in which two anisotropies of cosmic-ray particles (one of them, Δj1, from about 20 h L.T. and the other, Δj2, from about 8 h L.T. in interplanetary space) produce the solar diurnal variation of the cosmic-ray intensity on the earth.When the energy spectra of Δj1 and Δj2 are represented by [Formula: see text] and [Formula: see text], respectively, where j0(E) is the normal energy spectrum of the primary cosmic rays, it is shown that the evaluation for m1 = 1, 2, m2 = 0 and the cutoffs at 8 and 10 BeV on the low-energy side of spectra of both Δj1 and Δj2 agree well with the observational results at Deep River.

The results of simultaneous measurements of the cosmic-ray intensity over the Antarctic and Arctic

1968 ◽  
Vol 46 (10) ◽  
pp. S823-S824
Author(s):  
S. N. Vernov ◽  
A. N. Charakhchyan ◽  
T. N. Charakhchyan ◽  
Yu. J. Stozhkov
Keyword(s):  
Cosmic Rays ◽  
Temperature Effects ◽  
Cosmic Ray ◽  
Primary Component ◽  
Low Energy ◽  
Cosmic Ray Intensity ◽  
Simultaneous Measurements ◽  
Murmansk Region ◽  
The Antarctic

The results of the analysis of data obtained from measurements carried out by means of regular stratospheric launchings of cosmic-ray radiosondes over the Murmansk region and the Antarctic observatory in Mirny in 1963–66 are presented. The problem of the anisotropy of the primary component of low-energy cosmic rays and of temperature effects on the cosmic-ray intensity in the atmosphere are discussed.

scholarly journals 39. The anisotropy of primary cosmic radiation and the electromagnetic state in interplanetary space

1958 ◽  
Vol 6 ◽  
pp. 377-385
Author(s):  
V. Sarabhai ◽  
N. W. Nerurkar ◽  
S. P. Duggal ◽  
T. S. G. Sastry
Keyword(s):  
Experimental Data ◽  
Cosmic Rays ◽  
Cosmic Radiation ◽  
Interplanetary Space ◽  
Daily Variation ◽  
Cosmic Ray ◽  
The Sun ◽  
Cosmic Ray Intensity ◽  
Daily Variations ◽  
Primary Cosmic Radiation

Study of the anisotropy of cosmic rays from the measurement of the daily variation of meson intensity has demonstrated that there are significant day-today changes in the anisotropy of the radiation. New experimental data pertaining to these changes and their solar and terrestrial relationships are discussed.An interpretation of these changes of anisotropy in terms of the modulation of cosmic rays by streams of matter emitted by the sun is given. In particular, an explanation for the existence of the recently discovered types of daily variations exhibiting day and night maxima respectively, can be found by an extension of some ideas of Alfvén, Nagashima, and Davies. An integrated attempt is made to interpret the known features of the variation of cosmic ray intensity in conformity with ideas developed above.

Time and other Variations in the Intensity of Cosmic Ray Neutrons

1951 ◽  
Vol 6 (11) ◽  
pp. 592-598
Author(s):  
N. Adams ◽  
H. J. J. Braddick
Keyword(s):  
Cosmic Rays ◽  
Solar Flare ◽  
Diurnal Variation ◽  
Sea Level ◽  
Geomagnetic Latitude ◽  
Cosmic Ray ◽  
Temporal Variations ◽  
Neutron Production ◽  
Neutron Intensity

AbstractWe have measured the barometer coefficient of cosmic ray neutron production at sea level and find the value -9,25% ± 0,20/cmHg. We have shown that there is no diurnal variation of neutron production of amplitude greater than about 0,4 %. The effects of the large solar flare of November 19 th , 1949 on cosmic ray neutrons were much greater than on ionising cosmic rays at sea level; the maximum factor of increase was more than 5 and the intensity remained measurably above normal for about 12 hours. A small increase of neutron intensity is found, statistically, to be correlated with a number of recorded radio fade-outs. It is suggested that neutron measurements are particularly suitable for studying temporal variations of cosmic rays. The latitude increase of cosmic ray neutrons between geomagnetic latitude 54,5° and 56,5° was found to be about 2%. No certain increase was found between 56,5° and 59,5°.

scholarly journals On the heliolatitudinal variation of the galactic cosmic-ray intensity. Comparison with Ulysses measurements

2003 ◽  
Vol 21 (6) ◽  
pp. 1341-1345 ◽  
Author(s):  
G. Exarhos ◽  
X. Moussas
Keyword(s):  
Solar Wind ◽  
Cosmic Rays ◽  
Interplanetary Space ◽  
Cosmic Ray ◽  
Solar Wind Plasma ◽  
Simple Method ◽  
Cosmic Ray Intensity ◽  
Interplanetary Physics ◽  
Diffusion Convection ◽  
Galactic Cosmic Ray

Abstract. We study the dependence of cosmic rays with heliolatitude using a simple method and compare the results with the actual data from Ulysses and IMP spacecraft. We reproduce the galactic cosmic-ray heliographic latitudinal intensity variations, applying a semi-empirical, 2-D diffusion-convection model for the cosmic-ray transport in the interplanetary space. This model is a modification of our previous 1-D model (Exarhos and Moussas, 2001) and includes not only the radial diffusion of the cosmic-ray particles but also the latitudinal diffusion. Dividing the interplanetary region into "spherical magnetic sectors" (a small heliolatitudinal extension of a spherical magnetized solar wind plasma shell) that travel into the interplanetary space at the solar wind velocity, we calculate the cosmic-ray intensity for different heliographic latitudes as a series of successive intensity drops that all these "spherical magnetic sectors" between the Sun and the heliospheric termination shock cause the unmodulated galactic cosmic-ray intensity. Our results are compared with the Ulysses cosmic-ray measurements obtained during the first pole-to-pole passage from mid-1994 to mid-1995.Key words. Interplanetary physics (cosmic rays; interplanetray magnetic fields; solar wind plasma)

CHANGES IN THE DIURNAL HOUR OF MAXIMUM OF THE COSMIC-RAY INTENSITY

1961 ◽  
Vol 39 (10) ◽  
pp. 1477-1485
Author(s):  
J. Katzman
Keyword(s):  
Solar System ◽  
Interplanetary Space ◽  
Geomagnetic Latitude ◽  
Cosmic Ray ◽  
Cosmic Ray Intensity ◽  
Latitude Belt

The diurnal hour of maximum of the meson component changed progressively at Ottawa, Canada, from 10 hr 44 min to 14 hr 40 min during the period January 1955 to December 1960 while the nucleon component changed from 12 hr 12 min to 15 hr 16 min for the same period. This evidence favors the 22-year cycle in the diurnal hour of maximum that was first suggested by Thambyahpillai and Elliot, for stations within a geomagnetic latitude belt between 58.1° N. and 48.1° S. The diurnal hour of maximum at Churchill changed from 14 hr 40 min to 15 hr 24 min during the period April 1957 to December 1960 for the meson component and from 15 hr 12 min to 15 hr 52 min for the nucleon component. Although the change was for a later hour the indication of a 22-year cycle at Churchill is not impressive. At Resolute the diurnal hour of maximum is dominated by the varying magnetic masses in interplanetary space. It is shown that the anisotropy varies both in magnitude and direction depending on the conditions that exist in the solar system.

The solar-wind modulation of cosmic-ray intensity

1968 ◽  
Vol 46 (10) ◽  
pp. S954-S958 ◽  
Author(s):  
S. R. Sreenivasan ◽  
R. H. Johnson
Keyword(s):  
Solar Wind ◽  
Cosmic Rays ◽  
Correlation Coefficient ◽  
Solar Wind Velocity ◽  
Interplanetary Space ◽  
Dominant Role ◽  
Cosmic Ray ◽  
Normal Pattern ◽  
Cosmic Ray Intensity ◽  
Common Basis

It is shown from a consideration of the diffusion of cosmic rays in interplanetary space that the convection of particles by the solar wind is an important effect and hence should be incorporated in all discussions of the propagation of cosmic rays. This provides a common basis for looking at the correlation between relative changes of solar-wind velocity and changes of cosmic-ray intensity. The correlation is shown to be negative and significant. The correlation coefficient is large for a Forbush event, indicating that convection plays a dominant role during the event as contrasted with the normal pattern of changes of cosmic-ray intensity. The 11-year variation of cosmic-ray intensities and the Forbush event receive a natural interpretation on the basis of this discussion.

The composition of low-energy cosmic rays in 1965

1968 ◽  
Vol 46 (10) ◽  
pp. S539-S543 ◽  
Author(s):  
D. E. Hagge ◽  
V. K. Balasubrahmanyan ◽  
F. B. McDonald
Keyword(s):  
Cosmic Rays ◽  
Energy Range ◽  
Cosmic Ray ◽  
Low Energy ◽  
Oxygen Flux ◽  
Energy Spectra ◽  
Solar Modulation ◽  
Charge Composition ◽  
Specific Component ◽  
Relative Abundances

Primary cosmic-ray energy spectra and charge composition have been measured during the 1965 period of solar modulation minimum. A dE/dx vs. E type of scintillator–photomultiplier detector on board the eccentric-orbiting NASA spacecraft OGO-I was used. The charge composition was measured through neon over an energy range of 25 to 200 MeV/nucleon, depending upon the specific component. The spectra for all groups are nearly flat during this time, with the oxygen flux at about 0.005 nucleus/(M2-sr-s-MeV/nucleon). The relative abundances found are Li, 0.27; Be, 0.11; B, 0.37; C, 1.20; N, 0.30; O 1.00; F, [Formula: see text]; Ne, 0 12 An L/M ratio of 0.30 ± 0.06 is found.

Der Tagesgang der kosmischen Ultrastrahlung II

1956 ◽  
Vol 11 (7) ◽  
pp. 556-561
Author(s):  
E. Remy ◽  
A. Sittkus
Keyword(s):  
Cosmic Rays ◽  
Diurnal Variation ◽  
Zenith Angle ◽  
Cosmic Ray ◽  
Center Of Gravity ◽  
Cosmic Ray Intensity ◽  
Recurrence Tendency

The total cosmic-ray intensity was measured in 1953 near Freiburg i. Br. (48° N, 8° E, 1200 m) by a countertelescope in three different ranges of zenith-angle (center of gravity 10°, 20°, 30°). The behavior of inclined radiation with the center of gravity at 40° can be deduced from these measurements by calculation. From the examination of the diurnal variation, obtained by averaging over three days only, the following factors can be seen:1. There are often several maxima and minima during one day. The time, the height, and the number of maxima change from day to day.2. A correlation with earthmagnetic disturbances with 27-day-recurrence-tendency is indicated.3. The diurnal variation of cosmic-rays coming near the vertical differs strongly from those coming from inclined directions. The dependence of zenith-angle is variable.

scholarly journals Cosmic Ray Intensity Increase on January 28, 1967

1968 ◽  
Vol 21 (5) ◽  
pp. 755 ◽  
Author(s):  
LV Sud
Keyword(s):  
Solar Cycle ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
The Other ◽  
Intensity Increase ◽  
Cosmic Ray Intensity

During the present solar cycle, which started in October 1964, the ground-based cosmic ray detectors have so far recorded two increases in the intensity of cosmic rays. The first one was observed on July 7,1966 and the other on January 28,1967. Both these events were somewhat unusual in their characteristics.

Twenty-two-year revolutions in the cosmic-ray diurnal variations

1968 ◽  
Vol 46 (10) ◽  
pp. S934-S936
Author(s):  
M. Wada ◽  
S. Kudo
Keyword(s):  
Phase Difference ◽  
Geomagnetic Activity ◽  
Radial Flow ◽  
Interplanetary Space ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Rigid Rotation ◽  
The Other ◽  
The Sun ◽  
Other Hand

It is shown, from the data obtained during three complete sunspot cycles, that the 22-year variation in the phase of the cosmic-ray diurnal wave is associated with the 11-year revolutions of the diurnal vectors. The revolutions alternate in sense every 11 years. In order to interpret these revolutions, two perpendicular cosmic-ray streamings in interplanetary space are assumed. As both streamings undergo 11-year variations in their velocities, an ellipse is traced out by the termini of the annual vectors; the sense of revolution depends on whether the phase difference between the two is positive or negative. If, on the other hand, their periods are 11 and 22 years and if their phases coincide, the locus is a horseshoelike trajectory, which is traced twice by a to-and-fro motion during 22 years. The observed data available at this stage cannot distinguish between these possibilities. As geomagnetic activity also shows different 11-year variations alternately, its relation to the 22-year revolution in the diurnal variations is discussed. The radial flow of the cosmic-ray particles as well as the rigid rotation of the cosmic-ray gas with the sun suggested by Parker may correspond to the two streamings.

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