CHANGES IN THE INTENSITY LEVEL OF COSMIC RAYS AT FOUR STATIONS IN CANADA

1962 ◽  
Vol 40 (10) ◽  
pp. 1319-1331 ◽  
Author(s):  
J. Katzman ◽  
D. C. Rose
Keyword(s):  
Solar Cycle ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Anomalous Behavior ◽  
Solar Flux ◽  
Intensity Level ◽  
Cosmic Ray Intensity ◽  
The Mean ◽  
Resolute Bay ◽  
Magnetic Index

The mean annual intensity of the nucleon and meson components of the cosmic-ray intensity at Ottawa, Churchill, and Sulphur Mountain was at a minimum for the year September 1957 to August 1958 when the mean annual intensity of the 10.7-cm radio solar flux was at a maximum and the annual mean of the interplanetary magnetic index Kp was at its first maximum since the low at the beginning of the present solar cycle. At Resolute Bay the mean annual intensity of the nucleon and meson components was at a minimum for the year July 1959 to June 1960 when the interplanetary magnetic index Kp was at a second maximum. The anomalous behavior at Resolute Bay is attributed to a combination of spectral differences and directional effects.

Solar rotational period of cosmic rays and solar activity during the maximum phase of solar cycle 24

2021 ◽  
Author(s):  
Prithvi Raj Singh ◽  
A. I. Saad Farid ◽  
Y. P. Singh ◽  
A. K. Singh ◽  
Ayman A. Aly
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
R Package ◽  
Least Square ◽  
Maximum Phase ◽  
Cosmic Ray Intensity ◽  
Solar Cycle 24 ◽  
Cycle 24

Abstract To study the solar rotational oscillation on daily averaged time series of solar activity proxies: sunspot number (SSN), modified coronal index (MCI), solar flare index (FI), and cosmic ray intensity (CRI) are subjected to Lomb/Scargle periodogram, and continuous wavelet transform. For this purpose, we have used data of all the considered parameters from 2012 to 2015, which covers the maximum phase including the polarity reversal period of the solar cycle 24. Both spectral analysis techniques are carried out to study the behavior of 27-days on the time scale of the synodic period and to follow their evolution throughout the epoch. Further, we have used R package RobPer (least square regression) techniques and obtained a significant true period ~27 days is present in this study. It is noted that the ~27-day period of solar activity parameters and cosmic rays is much prominent during the examined period.

scholarly journals The seasonal variations of cosmic-ray intensity and temperature of the atmosphere

1941 ◽  
Vol 177 (969) ◽  
pp. 204-216 ◽  
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
The United States ◽  
Careful Examination ◽  
Cosmic Ray Intensity ◽  
Mean Temperature ◽  
Atmospheric Data ◽  
The Mean ◽  
Additional Support ◽  
Autumn And Winter

A careful examination of the upper atmospheric data for Europe and the United States indicates that the mean temperature of the upper atmosphere in spring differs from that in summer more than from that in winter. The magnitude of the second difference as defined by (1) depends on the height of the atmosphere which is considered and is a maximum at a height of about 6 km. and changes sign at heights above 12 km. (figure 1). This lag in the warming of the atmosphere in spring is found to be paralleled by a lag in the diminution of intensity of the cosmic-rays. A similar phenomenon is found in autumn. The cooling of the atmosphere as a whole is found to be less between summer and autumn than between autumn and winter, though the effect is markedly less definite than in spring. The cosmic-ray variations are found to be correlated more closely with the mean temperature of the atmosphere up to 16 km. than with the temperature near the ground. This provides additional support for the theory of Blackett that the temperature variation of penetrating cosmic-rays is related to the instability of the mesotron. The temperature coefficient of the cosmic-rays as deduced from the seasonal data is found to be 0.18 %/° C, and this is in rough agreement with the prediction of the theory.

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.

The influence of transient solar-wind events on the cosmic-ray intensity modulation

2000 ◽  
Vol 78 (4) ◽  
pp. 293-302 ◽  
Author(s):  
I Sabbah
Keyword(s):  
Solar Wind ◽  
Solar Cycle ◽  
Cosmic Rays ◽  
High Speed ◽  
Cosmic Ray ◽  
Power Exponent ◽  
Cosmic Ray Intensity ◽  
Drift Model ◽  
Wind Events ◽  
The Imf

We have studied the behavior of cosmic rays observed by three stations during a time of high-speed solar-wind (HSSW) events. These stations cover the median rigidity range 16-164 GV. The influence of the IMF (interplanetary magnetic field) associated with HSSW has also been studied. Our analysis covers the period 1967-1986. Both the cosmic-ray intensity and geomagnetic activity are enhanced by coronal-mass-ejection events. The IMF magnitude and fluctuation are responsible for the depression of cosmic-ray intensity during HSSW events. This depression is rigidity dependent. Low-energy cosmic rays suffer more intensity depression. The rigidity spectrum of the cosmic-ray intensity decreases is dependent upon the phase of the solar cycle. It was steeper during the period 1979-1980. The power exponent is dependent upon the magnetic state of the solar cycle in support of the prediction of the drift model. PACS Nos.: 96.50Ci, 96.40-z

Solar-cycle phenomena in cosmic-ray intensity: Differences between even and odd cycles

1988 ◽  
Vol 42 (3) ◽  
pp. 233-244 ◽  
Author(s):  
H. Mavromichalaki ◽  
E. Marmatsouri ◽  
A. Vassilaki
Keyword(s):  
Solar Cycle ◽  
Cosmic Ray ◽  
Cosmic Ray Intensity ◽  
Odd Cycles

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 Cosmic ray spectra in planetary atmospheres

2008 ◽  
Vol 4 (S257) ◽  
pp. 471-473
Author(s):  
M. Buchvarova ◽  
P. Velinov
Keyword(s):  
Experimental Data ◽  
Solar Cycle ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Planetary Atmospheres ◽  
Galactic Cosmic Rays ◽  
Outer Planets ◽  
Practical Possibility ◽  
The Earth ◽  
Theoretical Results

AbstractOur model generalizes the differential D(E) and integral D(>E) spectra of cosmic rays (CR) during the 11-year solar cycle. The empirical model takes into account galactic (GCR) and anomalous cosmic rays (ACR) heliospheric modulation by four coefficients. The calculated integral spectra in the outer planets are on the basis of mean gradients: for GCR – 3%/AU and 7%/AU for anomalous protons. The obtained integral proton spectra are compared with experimental data, the CRÈME96 model for the Earth and theoretical results of 2D stochastic model. The proposed analytical model gives practical possibility for investigation of experimental data from measurements of galactic cosmic rays and their anomalous component.

scholarly journals Cosmic-ray propagation around the Sun: investigating the influence of the solar magnetic field on the cosmic-ray Sun shadow

2020 ◽  
Vol 633 ◽  
pp. A83
Author(s):  
J. Becker Tjus ◽  
P. Desiati ◽  
N. Döpper ◽  
H. Fichtner ◽  
J. Kleimann ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Activity ◽  
Solar Cycle ◽  
Cosmic Rays ◽  
Solar Magnetic Field ◽  
Cosmic Ray ◽  
High Energy ◽  
High Solar Activity ◽  
The Sun ◽  
Theoretical Understanding

The cosmic-ray Sun shadow, which is caused by high-energy charged cosmic rays being blocked and deflected by the Sun and its magnetic field, has been observed by various experiments, such as Argo-YBJ, Tibet, HAWC, and IceCube. Most notably, the shadow’s size and depth was recently shown to correlate with the 11-year solar cycle. The interpretation of such measurements, which help to bridge the gap between solar physics and high-energy particle astrophysics, requires a solid theoretical understanding of cosmic-ray propagation in the coronal magnetic field. It is the aim of this paper to establish theoretical predictions for the cosmic-ray Sun shadow in order to identify observables that can be used to study this link in more detail. To determine the cosmic-ray Sun shadow, we numerically compute trajectories of charged cosmic rays in the energy range of 5−316 TeV for five different mass numbers. We present and analyze the resulting shadow images for protons and iron, as well as for typically measured cosmic-ray compositions. We confirm the observationally established correlation between the magnitude of the shadowing effect and both the mean sunspot number and the polarity of the magnetic field during the solar cycle. We also show that during low solar activity, the Sun’s shadow behaves similarly to that of a dipole, for which we find a non-monotonous dependence on energy. In particular, the shadow can become significantly more pronounced than the geometrical disk expected for a totally unmagnetized Sun. For times of high solar activity, we instead predict the shadow to depend monotonously on energy and to be generally weaker than the geometrical shadow for all tested energies. These effects should become visible in energy-resolved measurements of the Sun shadow, and may in the future become an independent measure for the level of disorder in the solar magnetic field.

scholarly journals Gamma Rays from Cosmic Rays

1981 ◽  
Vol 94 ◽  
pp. 309-319 ◽  
Author(s):  
A. W. Wolfendale
Keyword(s):  
Cosmic Rays ◽  
Gamma Rays ◽  
Molecular Clouds ◽  
Cosmic Ray ◽  
Cosmic Ray Intensity ◽  
Cosmic Ray Interactions ◽  
The Galaxy ◽  
Γ Rays ◽  
Γ Ray

It is shown that there is evidence favouring molecular clouds being sources of γ-rays, the fluxes being consistent with expectation for ambient cosmic rays interacting with the gas in the clouds for the clouds considered. An estimate is made of the fraction of the apparently diffuse γ-ray flux which comes from cosmic ray interactions in the I.S.M. as distinct from unresolved discrete sources. Finally, an examination is made of the possibility of gradients of cosmic ray intensity in the Galaxy.

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