On the possibility of a two-way solar anisotropy producing the cosmic-ray diurnal variation

1968 ◽  
Vol 46 (10) ◽  
pp. S825-S827
Author(s):  
M. Kodama ◽  
K. Nagashima
Keyword(s):  
Diurnal Variation ◽  
High Altitude ◽  
Experimental Evidence ◽  
Sea Level ◽  
Phase Difference ◽  
Solar Rotation ◽  
Theoretical Calculations ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Neutron Component

Two pieces of experimental evidence, which are inconsistent with the hypothesis of a one-way solar anisotropy as an interpretation of the cosmic-ray diurnal variation, are presented. The diurnal variation of the temperature-corrected meson component at Deep River was examined and compared with that of the neutron component. Both diurnal variations were averaged for each solar rotation from No. 1762 to No. 1787. If a one-way solar anisotropy is assumed, the time of maximum for neutrons should be about half an hour earlier than that for mesons at Deep River. However, the observations show that the phase difference between the two components is the reverse of that expected. Further evidence is obtained from a comparison of the diurnal variation on Mt. Norikura (2 770 m, 11.4 GeV) to that in Itabashi (20 m, 11.5 GeV). According to theoretical calculations based on a one-way solar anisotropy, the time of maximum at high altitude is earlier than or equal to that at sea level, but observations obtained during Dec. 1966 to Mar. 1967 suggest that the opposite is true.

PERIODICAL FLUCTUATION STUDIES OF COSMIC-RAY DIURNAL VARIATIONS DURING THE QUIET-SUN PERIOD 1962–64

1967 ◽  
Vol 45 (8) ◽  
pp. 2733-2748 ◽  
Author(s):  
Masahiro Kodama
Keyword(s):  
Diurnal Variation ◽  
Solar Minimum ◽  
Counting Rate ◽  
Solar Rotation ◽  
Rotation Period ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Statistical Studies ◽  
Periodic Fluctuations ◽  
Recurrence Tendency

Statistical studies of periodic fluctuations of the cosmic-ray diurnal variation have been performed, using neutron and meson component data obtained by the high-counting-rate cosmic-ray monitors at Deep River. The data cover an interval from May 1962 to October 1964, a period of descending solar activity ending near the solar minimum. It is shown that a 27-day recurrence tendency of the amplitude of the diurnal variation occasionally appears as well as shorter recurrent variations, ranging from one-half to one-sixth of the solar rotation period. The correlations of these fluctuations with some typical solar and terrestrial indices are examined in order to search for possible origins of the shorter recurrent variations. A possible connection with the Kp index exists.

scholarly journals Observing the neutron component during thunderstorm activity at a mountain CR station

2019 ◽  
Vol 5 (3) ◽  
pp. 54-58
Author(s):  
Анна Луковникова ◽  
Anna Lukovnikova ◽  
Виктор Алешков ◽  
Viktor Aleshkov ◽  
Алексей Лысак ◽  
...  
Keyword(s):  
Field Strength ◽  
Sea Level ◽  
Neutron Monitor ◽  
Electromagnetic Interference ◽  
Count Rate ◽  
Cosmic Ray ◽  
Thunderstorm Activity ◽  
Signal Discrimination ◽  
Lightning Discharges ◽  
Neutron Component

During three summer months in 2015, the Cosmic Ray (CR) station Irkutsk-3000, located at 3000 m above sea level, measured the CR neutron component intensity with the 6NM64 neutron monitor, as well as the atmospheric electric field strength and the level of electromagnetic interference during lightning discharges. It is shown that the level of electromagnetic interference, when registered during lightning discharges, depends considerably on the fixed level of signal discrimination. During observations, we observed no effects of thunderstorm discharges at the neutron monitor count rate at the CR station Irkutsk-3000.

Enhanced Cosmic Ray Diurnal Variations in Mawson and Hobart Neutron Monitor and Underground Data Records

1990 ◽  
Vol 8 (3) ◽  
pp. 268-273 ◽  
Author(s):  
M. L. Duldig ◽  
J. E. Humble
Keyword(s):  
Diurnal Variation ◽  
Neutron Monitor ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Rigidity Spectrum ◽  
Underground Detector ◽  
Preliminary Study

AbstractAnalysis of surface and underground detector data from Mawson and Hobart for the period 1982 to 1988 has revealed a number of episodes of enhanced diurnal variation lasting more than 5 days. A preliminary study of these enhancements shows that variations in the rigidity spectrum and in the upper limiting rigidity must be present to explain the phenomenon.

scholarly journals The Upper Limiting Primary Rigidity of the Cosmic Ray Solar Anisotropy

1965 ◽  
Vol 18 (5) ◽  
pp. 451 ◽  
Author(s):  
RM Jacklyn ◽  
JE Humble
Keyword(s):  
Diurnal Variation ◽  
Sea Level ◽  
Free Space ◽  
Daily Variation ◽  
Cosmic Ray ◽  
Neutron Monitors ◽  
Annual Average ◽  
Average Value

A method of determining the upper limiting rigidity of the solar diurnal variation of the cosmic ray primaries in free space is described. It involves a comparision of the response to the anisotropy of neutron monitors at sea level and of meson telescopes underground. Making use of the model for the free-space first harmonic proposed by Radio, McCracken, and Venkatesan, the annual average value for the upper limiting rigidity (Ru) in 1958 is estimated to have been 95 GV with an error of estimate of about 10-20 GV. Changes in the observed annual mean daily variation between 1958 and 1962 indicate that Ru may have decreased by about 20-40 GV over this period, but a more refined analysis is needed to confirm this.

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°.

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.

scholarly journals The Diurnal Variation of the Barometer Coefficient for Cosmic Rays at Hobart

1956 ◽  
Vol 9 (4) ◽  
pp. 505
Author(s):  
RM Jacklyn
Keyword(s):  
Cosmic Rays ◽  
Diurnal Variation ◽  
Sea Level ◽  
Cosmic Radiation ◽  
Diurnal Variations ◽  
Hard Component ◽  
Secular Changes ◽  
The Mean ◽  
Counter Telescope

The records from a vertical counter telescope measuring the hard component of cosmic radiation at sea-level have disclosed significant diurnal variations of the barometer coefficient at Hobart, Tas. The amplitude of the variation is about 5 per cent., and there are secular changes of the same order during the mean day.

scholarly journals Observing the neutron component during thunderstorm activity at a mountain CR station

2019 ◽  
Vol 5 (3) ◽  
pp. 64-69
Author(s):  
Анна Луковникова ◽  
Anna Lukovnikova ◽  
Виктор Алешков ◽  
Viktor Aleshkov ◽  
Алексей Лысак ◽  
...  
Keyword(s):  
Field Strength ◽  
Sea Level ◽  
Neutron Monitor ◽  
Electromagnetic Interference ◽  
Count Rate ◽  
Cosmic Ray ◽  
Thunderstorm Activity ◽  
Signal Discrimination ◽  
Lightning Discharges ◽  
Neutron Component

During three summer months in 2015, the Cosmic Ray (CR) station Irkutsk-3000, located at 3000 m above sea level, measured the CR neutron component intensity with the 6NM64 neutron monitor, as well as the atmospheric electric field strength and the level of electromagnetic interference during lightning discharges. It is shown that the level of electromagnetic interference, when registered during lightning discharges, depends considerably on the fixed level of signal discrimination. During observations, we observed no effects of thunderstorm discharges at the neutron monitor count rate at the CR station Irkutsk-3000.

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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