Modulation effect of magnetic corotating trap on 27-day cosmic ray variation in November–December 2014

We study the 27-day cosmic-ray (CR) intensity variation occurring in November–December 2014, using ground-based measurements from the worldwide network of neutron monitors and GOES-15 satellites. A determining factor in the considerable difference between amplitudes of the 27-day CR variation in November–December 2014 is shown to be significant changes in energy losses taking place when particles move in regular heliospheric electromagnetic fields. In this period, there was a long-living corotating trap produced by a vast coronal hole in the south of the Sun in interplanetary space. Configuration of this trap induced the energy loss of ~3–20 GeV CRs, due to which ground-based neutron monitors recorded an abnormally large amplitude of the 27-day variation.

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Diurnal cosmic-ray variation with the inclusion of the geometrical effects and the asymptotic cones of approach

Canadian Journal of Physics ◽

10.1139/p68-356 ◽

1968 ◽

Vol 46 (10) ◽

pp. S809-S811 ◽

Cited By ~ 1

Author(s):

L. I. Dorman ◽

S. Fischer

Keyword(s):

Spatial Distribution ◽

High Latitude ◽

Intensity Variation ◽

Cosmic Ray ◽

The Sun ◽

Neutron Monitors ◽

Asymptotic Cones ◽

Diurnal Anisotropy ◽

Geometrical Effects

Employing the data from cosmic-ray neutron monitors at high latitude, the spatial distribution of the axis of the diurnal anisotropy is determined. The effects of the earth's revolution around the sun on the diurnal intensity variation is investigated. A new method for further investigation of the spatial distribution of the anisotropy and for the determination of its spectra in various directions has been proposed.

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

Symposium - International Astronomical Union ◽

10.1017/s0074180900237959 ◽

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.

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On the nature of some anomalies in the cosmic-ray distribution

Canadian Journal of Physics ◽

10.1139/p68-308 ◽

1968 ◽

Vol 46 (10) ◽

pp. S614-S616 ◽

Cited By ~ 1

Author(s):

N. P. Chirkov ◽

G. F. Krymsky ◽

A. I. Kuzmin

Keyword(s):

Magnetic Field ◽

Diurnal Variation ◽

Interplanetary Magnetic Field ◽

Equatorial Plane ◽

Geomagnetic Field ◽

Cosmic Ray ◽

Neutron Monitors ◽

Vector Method ◽

Worldwide Network ◽

Northern And Southern Hemispheres

Diurnal and semidiurnal variations of the data from the worldwide network of neutron monitors during 1958 are analyzed using the receiving-vector method. It is shown that there exists an "antisymmetric" diurnal variation, i.e., a variation with opposite phases in the northern and southern hemispheres. After correction for the distortion due to the geomagnetic field, it is found that this variation has an amplitude of 0.03% and an hour of maximum at 21.5 hours in the northern hemisphere. If the variation is due to cosmic-ray screening in the interplanetary magnetic field, this field must have a slope of 7° with respect to the solar equatorial plane.

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IONIZATION LOSS BY COSMIC-RAY MU-MESONS IN ARGON

Canadian Journal of Physics ◽

10.1139/p59-025 ◽

1959 ◽

Vol 37 (2) ◽

pp. 189-202 ◽

Cited By ~ 2

Author(s):

Georges Hall

Keyword(s):

Experimental Data ◽

Energy Loss ◽

Ionization Chamber ◽

Cosmic Ray ◽

Statistical Distribution ◽

Experimental Curve ◽

Energy Losses ◽

Ionization Loss ◽

Electron Collection ◽

Probable Loss

The ionization of argon by cosmic-ray mu-mesons of minimum specific ionization has been studied by means of a calibrated pressure-ionization chamber using electron collection. Corrections which are shown to be necessary have been applied to the experimental data. The shape of the experimental curve of statistical distribution of energy loss agrees with the theoretically predicted shape, for energy losses greater than the most probable loss (300 kev).

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Energetic solar particle propagation and the structure of interplanetary space

Canadian Journal of Physics ◽

10.1139/p68-357 ◽

1968 ◽

Vol 46 (10) ◽

pp. S812-S818 ◽

Cited By ~ 2

Author(s):

S. N. Vernov ◽

E. V. Gortchakov ◽

Yu. I. Logatchov ◽

G. P. Lyubimov ◽

N. V. Pereslegina ◽

...

Keyword(s):

Solar Activity ◽

Interplanetary Space ◽

Cosmic Ray ◽

Solar Proton ◽

The Sun ◽

Energetic Solar Particle ◽

Radial Gradient ◽

Solar Particle ◽

Proton Fluxes ◽

Particle Propagation

This work studies the structure of interplanetary space between the orbits of Venus and Mars on the basis of solar proton streaming and cosmic-ray variations measured from Soviet and U.S. spacecraft. Solar proton fluxes measured from spacecraft at various distances from the sun and in various solar activity phases are intercompared. The problem of the large radial gradient of protons with energies of 1–5 MeV is discussed.

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Prediction of galactic cosmic ray intensity variation for a few (up to 10-12) years ahead on the basis of convection-diffusion and drift model

Annales Geophysicae ◽

10.5194/angeo-23-3003-2005 ◽

2005 ◽

Vol 23 (9) ◽

pp. 3003-3007 ◽

Cited By ~ 5

Author(s):

L. I. Dorman

Keyword(s):

Interplanetary Space ◽

Intensity Variation ◽

Cosmic Ray ◽

Particle Energy ◽

Cosmic Ray Intensity ◽

Convection Diffusion ◽

Drift Model ◽

Galactic Cosmic Ray ◽

Near Future

Abstract. We determine the dimension of the Heliosphere (modulation region), radial diffusion coefficient and other parameters of convection-diffusion and drift mechanisms of cosmic ray (CR) long-term variation, depending on particle energy, the level of solar activity (SA) and general solar magnetic field. This important information we obtain on the basis of CR and SA data in the past, taking into account the theory of convection-diffusion and drift global modulation of galactic CR in the Heliosphere. By using these results and the predictions which are regularly published elsewhere of expected SA variation in the near future and prediction of next future SA cycle, we may make a prediction of the expected in the near future long-term cosmic ray intensity variation. We show that by this method we may make a prediction of the expected in the near future (up to 10-12 years, and may be more, in dependence for what period can be made definite prediction of SA) galactic cosmic ray intensity variation in the interplanetary space on different distances from the Sun, in the Earth's magnetosphere, and in the atmosphere at different altitudes and latitudes.

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The Cosmic Ray Ground-level Enhancement of 24 October 1989

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000019627 ◽

1994 ◽

Vol 11 (1) ◽

pp. 28-32 ◽

Cited By ~ 4

Author(s):

J. L. Cramp ◽

J. E. Humble ◽

M. L. Duldig

Keyword(s):

Pitch Angle ◽

Cosmic Ray ◽

Ground Level ◽

Model Fit ◽

South Pole ◽

Neutron Monitors ◽

Ground Level Enhancement ◽

Apparent Source ◽

Worldwide Network ◽

Monitor Data

AbstractThe cosmic ray ground-level enhancement (GLE) of 24 October 1989 was the last of a series of GLEs associated with the same solar active region. Intensity enhancements were observed by at least 31 neutron monitors in the worldwide network, with the largest increase (~200%) observed at South Pole, Antarctica around 20:30 UT. Using a least-squares model fit to all available neutron monitor data, spectra, apparent source directions and particle pitch angle distributions have been derived. The effect of disturbed geomagnetic conditions has also been taken into account.

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Evidence for the existence of adiabatic energy loss in interplanetary space from observations of the decay of the February 25?March 2, 1969 series of solar cosmic ray events

Solar Physics ◽

10.1007/bf00165289 ◽

1972 ◽

Vol 26 (2) ◽

pp. 474-483 ◽

Cited By ~ 3

Author(s):

J. A. Lezniak ◽

W. R. Webber

Keyword(s):

Energy Loss ◽

Interplanetary Space ◽

Cosmic Ray ◽

Adiabatic Energy

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Limits on Source Distances for the Most Energetic Cosmic Rays

Publications of the Astronomical Society of Australia ◽

10.1071/as97258 ◽

1997 ◽

Vol 14 (3) ◽

pp. 258-264 ◽

Cited By ~ 3

Author(s):

R. Lampard ◽

R. W. Clay ◽

B. R. Dawson

Keyword(s):

Cosmic Rays ◽

Energy Loss ◽

Power Law ◽

Pion Production ◽

Cosmic Ray ◽

Source Spectrum ◽

Energy Losses ◽

Microwave Background ◽

Energy Degradation

AbstractThe propagation of the highest energy cosmic rays through the 2·7 K microwave background is considered. Photo-pion production interactions cause energy losses for primary cosmic ray protons which result in significant energy degradation over intergalactic distances. The process of energy loss is discussed and an estimate is made of the average distances travelled for observed cosmic rays with a range of energies, assuming a power law source spectrum. At energies over 1020 eV, the average distances travelled are a few tens of megaparsecs, limiting possible sources to the volume dominated by the supergalactic plane.

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