Association Between the Solar Wind Speed, Interplanetary Magnetic Field and the Cosmic Ray Intensity for Solar Cycles 23 and 24

2017 ◽  
Vol 38 (4) ◽  
Author(s):  
Meena Pokharia ◽  
Lalan Prasad ◽  
Chandni Mathpal ◽  
Chandrasekhar Bhoj ◽  
Hema Kharayat ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Wind Speed ◽  
Interplanetary Magnetic Field ◽  
Solar Wind Speed ◽  
Cosmic Ray ◽  
Solar Cycles ◽  
Cosmic Ray Intensity

scholarly journals Solar Cycle Variation of Cosmic ray Intensity along with Interplanetary and Solar Wind Plasma Parameters

2008 ◽  
Vol 45 (3) ◽  
pp. 63-68 ◽  
Author(s):  
Rajesh Mishra ◽  
Rekha Agarwal ◽  
Sharad Tiwari
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Solar Cycle ◽  
Interplanetary Magnetic Field ◽  
Cosmic Ray ◽  
Solar Wind Plasma ◽  
Solar Cycles ◽  
Plasma Parameters ◽  
Solar Cycle Variation ◽  
Cosmic Ray Intensity

Solar Cycle Variation of Cosmic ray Intensity along with Interplanetary and Solar Wind Plasma ParametersGalactic cosmic rays are modulated at their propagation in the heliosphere by the effect of the large-scale structure of the interplanetary medium. A comparison of the variations in the cosmic ray intensity data obtained by neutron monitoring stations with those in geomagnetic disturbance, solar wind velocity (V), interplanetary magnetic field (B), and their product (V' B) near the Earth for the period 1964-2004 has been presented so as to establish a possible correlation between them. We used the hourly averaged cosmic ray counts observed with the neutron monitor in Moscow. It is noteworthy that a significant negative correlation has been observed between the interplanetary magnetic field, product (V' B) and cosmic ray intensity during the solar cycles 21 and 22. The solar wind velocity has a good positive correlation with cosmic ray intensity during solar cycle 21, whereas it shows a weak correlation during cycles 20, 22 and 23. The interplanetary magnetic field shows a weak negative correlation with cosmic rays for solar cycle 20, and a good anti-correlation for solar cycles 21-23 with the cosmic ray intensity, which, in turn, shows a good positive correlation with disturbance time index (Dst) during solar cycles 21 and 22, and a weak correlation for cycles 20 and 23.

scholarly journals Responses and Periodic Variations of Cosmic Ray Intensity and Solar Wind Speed to Sunspot Numbers

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Jacob Oloketuyi ◽  
Yu Liu ◽  
Amobichukwu Chukwudi Amanambu ◽  
Mingyu Zhao
Keyword(s):  
Solar Wind ◽  
Wind Speed ◽  
Solar Wind Speed ◽  
Phase Relationship ◽  
Cosmic Ray ◽  
Strong Negative Correlation ◽  
Cosmic Ray Intensity ◽  
Sunspot Numbers ◽  
Daily Data ◽  
Wide Range

To investigate the periodic behaviour and relationship of sunspot numbers with cosmic ray intensity and solar wind speed, we present analysis from daily data generated from 1995 January to 2018 December. Cross-correlation and wavelet transform tools were employed to carry out the investigation. The analyses confirmed that the cosmic ray intensity correlates negatively with the sunspot numbers, exhibiting an asynchronous phase relationship with a strong negative correlation. The trend in cosmic ray intensity indicates that it undergoes the 11-year modulation that mainly depends on the solar activity in the heliosphere. On the other hand, the solar wind speed neither shows a clear phase relationship nor correlates with the sunspot numbers but shows a wide range of periodicities that could possibly be connected to the pattern of coronal hole configuration. A number of short and midterm variations were also observed from the wavelet analysis, i.e., 64–128 and 128–256 days for the cosmic ray intensity, 4–8, 32–64, 128–256, and 256–512 days for the solar wind speed, and 16–32, 32–64, 128–256, and 256–512 days for the sunspot numbers.

scholarly journals The relativistic electron response in the outer radiation belt during magnetic storms

2002 ◽  
Vol 20 (7) ◽  
pp. 957-965 ◽  
Author(s):  
R. H. A. Iles ◽  
A. N. Fazakerley ◽  
A. D. Johnstone ◽  
N. P. Meredith ◽  
P. Bühler
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Wind Speed ◽  
Interplanetary Magnetic Field ◽  
Relativistic Electron ◽  
Radiation Belt ◽  
Solar Wind Speed ◽  
Recovery Phase ◽  
Magnetic Storms ◽  
Outer Radiation Belt

Abstract. The relativistic electron response in the outer radiation belt during magnetic storms has been studied in relation to solar wind and geomagnetic parameters during the first six months of 1995, a period in which there were a number of recurrent fast solar wind streams. The relativistic electron population was measured by instruments on board the two microsatellites, STRV-1a and STRV-1b, which traversed the radiation belt four times per day from L ~ 1 out to L ~ 7 on highly elliptical, near-equatorial orbits. Variations in the E > 750 keV and E > 1 MeV electrons during the main phase and recovery phase of 17 magnetic storms have been compared with the solar wind speed, interplanetary magnetic field z-component, Bz , the solar wind dynamic pressure and Dst *. Three different types of electron responses are identified, with outcomes that strongly depend on the solar wind speed and interplanetary magnetic field orientation during the magnetic storm recovery phase. Observations also confirm that the L-shell, at which the peak enhancement in the electron count rate occurs has a dependence on Dst *.Key words. Magnetospheric physics (energetic particles, trapped; storms and substorms) – Space plasma physics (charged particle motion and accelerations)

Galactic cosmic-ray modulation effect by solar-wind streams

1995 ◽  
Vol 73 (9-10) ◽  
pp. 642-646 ◽  
Author(s):  
M. A. El-Borie
Keyword(s):  
Solar Wind ◽  
Wind Speed ◽  
Cosmic Rays ◽  
Solar Wind Speed ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Solar Cycles ◽  
Mean Values ◽  
Wind Speeds ◽  
Cosmic Ray Modulation

Data, from the worldwide network of neutron monitors, recorded at Deep River, Hermanus, Rome, Tokyo, and Huancayo, over two solar cycles (Nos. 20 and 21) are analyzed to study the long-term variations of the solar diurnal variations as they relate to solar-wind speed. The median primary rigidities of response (Rm) for these detectors cover the range 16 GV ≤ Rm ≤ 33 GV. We discuss the solar diurnal variations (amplitude and phase) of cosmic rays as a function of solar activity. The behavior of solar diurnal phases is completely different for the two epochs of high-wind speed. Data of solar-wind speed from 1966–1986 are classified according to the state of the daily mean values. Variation in the amplitudes of the diurnal variations, as functions of the median primary rigidity of cosmic rays, for the two selected periods (1973–1975 and 1979–1981) of high and low solar-wind speeds were determined at the selected stations. The rigidity dependence of the averaged solar diurnal variations of cosmic rays related to the high solar-wind speed was studied. The most sensitive rigidity of modulation is around 20 and 30 GV during the 1973–1975 and 1979–1981 periods, respectively. Our results also show that there is a significant correlation in the solar diurnal amplitudes between the two divisions of high and low solar-wind speed days.

A study of the modulation regions causing 27-day cosmic-ray variations

1968 ◽  
Vol 46 (10) ◽  
pp. S970-S972 ◽  
Author(s):  
M. V. Alania ◽  
L. Kh. Shatashvili ◽  
L. I. Dorman
Keyword(s):  
Solar Wind ◽  
Wind Speed ◽  
Sunspot Number ◽  
Interplanetary Medium ◽  
Solar Wind Speed ◽  
Cosmic Ray ◽  
Effective Size ◽  
Neutron Data ◽  
Cosmic Ray Intensity ◽  
Sunspot Data

This is an attempt to determine the effective size of the interplanetary medium responsible for the 27-day variation in the cosmic-ray intensity. Neutron data from Mt. Norikura and Climax have been correlated with sunspot data for 80 solar revolutions beginning July 1957. The size of the modulating region was estimated from the lag between the sunspot number and the cosmic-ray variations, assuming the solar wind speed to be 400 km s−1, and it was found to be comparable with, or less than, the effective size of the modulating region causing the 11-year variation.

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