Solar neutrino flux, cosmic rays, and the solar activity cycle

Solar Physics ◽  
1986 ◽  
Vol 104 (2) ◽  
pp. 415-424 ◽  
Author(s):  
Probhas Raychaudhuri
1991 ◽  
Vol 06 (22) ◽  
pp. 2003-2007 ◽  
Author(s):  
PROBHAS RAYCHAUDHURI

Solar neutrino flux (Eν ≥ 7.5 MeV ) data from 1st January to April 1990 as measured in Kamiokande solar neutrino experiment have been analyzed statistically and have found that the solar neutrino data varies with the solar activity cycle with very high statistical significance (> 98% confidence level). Average solar neutrino flux data in the sunspot minimum range cannot be equal to twice the average solar neutrino flux data in the sunspot maximum range, which suggests that the neutrino flip through the magnetic field of the convection zone of the sun is not responsible for the solar neutrino flux variation. Thus the variation of solar neutrino flux with the solar activity cycle suggests that the solar activity cycle is due to the pulsating character of the nuclear energy generation inside the core of the sun.


1999 ◽  
Vol 14 (08) ◽  
pp. 1205-1223
Author(s):  
PROBHAS RAYCHAUDHURI

It is suggested that the experimental data on the solar neutrino flux as measured in the existing solar neutrino detectors (e.g. Homestake, Kamiokande II and III, Gallex and Sage) vary with the solar activity cycle to a very high level of statistical significance. We have applied the run test and the change point test to the nine sets of solar neutrino flux that have been generated by the Monte-Carlo simulation with production rate and background parameters that are typical of those in the actual Homestake experiment. Homestake solar neutrino flux data show anticorrelation with sunspot numbers from 1970 to February 1994 at a very high level of statistical significance. However, the Kamiokande solar neutrino flux data show correlation with the sunspot number data at a significant level. Again it is shown that out of nine Monte-Carlo-simulated data only three indicate a variation within the period from 1970 to February 1992, but these three Monte-Carlo-simulated solar neutrino flux data do not show significant anticorrelation with the sunspot number data. The solar neutrino flux data from Gallex and Sage show not only variation within the measurement period, i.e. from January 1990 to October 1995, but are also correlated with the sunspot numbers. The Kamiokande solar neutrino flux data not only show variation from January 1987 to February 1995 but are also correlated with the sunspot number data. The variation of solar neutrino flux data within the solar activity cycle and anticorrelation/correlation indicates that the solar activity cycle is due to the pulsating character of the nuclear energy generation inside the core of the sun.


1998 ◽  
Vol 13 (14) ◽  
pp. 1109-1114 ◽  
Author(s):  
PROBHAS RAYCHAUDHURI

The 8 B solar neutrino flux observed in Kamiokande detector (KAMIOKANDE II and III) from January 1987 to February 1995 has been analysed statistically and it has been found that solar neutrino flux data in Kamiokande detector varies with the solar activity cycle. It is also shown that solar neutrino flux data in Kamiokande detector also has five phases during the solar cycle 22 as observed in the Homestake solar neutrino flux data during the solar cycles 21 and 22 indicating that the solar activity cycle is due to the pulsating character of the nuclear energy generation inside the core of the sun.


1993 ◽  
Vol 08 (21) ◽  
pp. 1961-1968 ◽  
Author(s):  
PROBHAS RAYCHAUDHURI

Considering the solar neutrino data during the period from June, 1989 to April, 1992 within first sunspot maximum (it coincides with the maximum of the sunspot (Wolf numbers) and second sunspot maximum (usually appears 2–3 years after the first sunspot maximum) from the four solar neutrino experiments (37 Cl radiochemical, SAGE I & II, Gallex, Kamiokande II & III) we see that the average solar neutrino flux is much higher at the second sunspot maximum (May, 1991 to April, 1992) than at the first sunspot maximum (June, 1989 to April, 1991). This type of observation is already observed in the previous two solar activity cycles in 37 Cl solar neutrino experiment. It has been known for many years that first sunspot maximum and second sunspot maximum are essential features of the solar activity cycle. The above observation suggests that the solar neutrino flux data from the solar neutrino experiments appear to be varying with the solar activity cycle which suggests that the solar activity cycle is due to the pulsating character of the nuclear energy generation inside the core of the Sun.


1988 ◽  
Vol 03 (14) ◽  
pp. 1319-1322 ◽  
Author(s):  
PROBHAS RAYCHAUDHURI

It is shown that the sunspot data and the solar neutrino data anticorrelates except for the period of three years after the sunspot maximum. This suggests that the solar activity cycle is due to the pulsating character of the nuclear energy generation inside the core of the sun.


1968 ◽  
Vol 46 (10) ◽  
pp. S927-S929
Author(s):  
Yu. Stozhkov ◽  
T. N. Charakhchyan

The energy spectrum of galactic cosmic rays has been investigated for various periods of the solar activity. In the framework of commonly used ideas about the mechanism of the 11-year variation according to Parker the dependence of the cosmic-ray diffusion coefficient, D, on the particle rigidity, P, was determined. For the form D ≈ vpα the parameter α is found to change during the cycle of the solar activity.[Formula: see text]


1998 ◽  
Vol 185 ◽  
pp. 465-466
Author(s):  
L.K. Ding ◽  
M. Nishizawa ◽  
T. Sasaki ◽  
Y.H. Tan ◽  
Y. Yamamoto ◽  
...  

Air shower arrays with high counting rates at high altitude provide a unique means for the study of the time dependence of the Sun's shadow as seen in cosmic rays (Amenomori et al. 1992). With the Tibet-I array, operated from 1990 to 1993 at Yangbajing (4300m), we detected for the first time the influence of the solar and interplanetary magnetic fields (IMF) on the Sun's shadow. In this experiment the Sun's shadow seen by 10 TeV cosmic rays was found at a position 0.°7 away from the position of the Sun. This large displacement is considered to be caused by IMF which changed considerably in 1990-1993, near maximum, and during the declining phase of solar activity (cycle 22). A new Tibet-II array, enlarged in 1994, with a seven times larger effective area than the Tibet-I, has been operating since 1995 and allows us to observe the Sun's shadow every 3-4 months. The solar activity, being in the most quiet phase now in 1995-1997, will return to more active phase in 1998. Here, we present some results obtained in 1996 with Tibet-II array.


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