V. Analysis of IQSY cosmic-ray survey measurements

1969 ◽  
Vol 47 (19) ◽  
pp. 2073-2093 ◽  
Author(s):  
H. Carmichael ◽  
M. Bercovitch

In this, the last of a set of five papers reporting latitude surveys carried out in 1965 and 1966 at the time of and soon after the IQSY cosmic-ray maximum, the observations are reduced to a common atmospheric depth and at the same time the attenuation coefficients in the atmosphere for both the neutron monitor and the muon monitor are determined as functions of altitude and latitude. The latitude variation of the neutron monitor at sea level is compared with observations reported for the previous cosmic-ray maximum in 1954–55 and found to be similar. The altitude variation of the neutron-monitor attenuation coefficient is discussed in detail with reference to the maximum near 600 mm Hg currently attributed to neutrons produced in the monitor by stopping muons. It is shown that the stopping-muon effect is insufficient to account for the maximum. It is shown, using the Gross transformation, that a geometrical effect associated with the omnidirectional nature of the incident cosmic radiation may be the main factor producing the maximum. A specific absorption coefficient representing the differential effect in the neutron monitor of vertically-incident primaries of given magnetic rigidity is deduced. Good agreement is obtained with the observed attenuation in the atmosphere of solar protons of mean energy 2 GV and also with the reported results of a Monte Carlo calculation of the attenuation of the nucleonic cascade in air.

1969 ◽  
Vol 47 (19) ◽  
pp. 2057-2065 ◽  
Author(s):  
H. Carmichael ◽  
M. A. Shea ◽  
R. W. Peterson

A 3-NM-64 neutron monitor and a 2-MT-64 muon monitor were operated at 29 sites near sea level and on mountains on the western seaboard of the USA and in Hawaii in May, June, and July, 1966, in continuation of the latitude survey begun in 1965 and reported in papers I and II of this set of five papers. The original results and also the corrections for temperature structure of the atmosphere and for secular variations of the cosmic radiation are given in detail. While the overland equipment was at its highest altitude on Mt. Hood (2.4 GV) and on the summits of Mt. Palomar (5.7 GV) and Mt. Haleakela (13.3 GV), an airborne neutron monitor was operated at seven different levels between 3000 m and 12 000 m. The pressure-measuring equipment and also the neutron monitor in the aircraft were calibrated in terms of the overland instruments while the aircraft was at the same altitude as the overland equipment on the summit of Mt. Haleakela.


1968 ◽  
Vol 46 (10) ◽  
pp. S903-S906 ◽  
Author(s):  
J. A. Lockwood ◽  
W. R. Webber

The variation in the cosmic-ray intensity recorded by neutron monitors from 1958 to 1965 has been investigated to deduce the form of the solar modulation of the cosmic radiation. The observed changes in the intensity at the neutron monitor stations, averaged over quarter-year periods, were compared with changes calculated using modulation functions depending upon energy, rigidity, and velocity × rigidity. These calculations were based upon the revised differential response functions deduced by Lockwood and Webber (1967). The variance between the observed and calculated changes in the neutron monitor intensities at different stations was minimized to determine the best form of the solar modulation function. We find that the change of the primary cosmic radiation, deduced from the change in the neutron monitor intensity as well as from direct measurements of the primary flux, can be described by a modulation of the form exp(–K/P) in the rigidity range 0.5 < P < 50 GV. The change between 1959 and 1965 can be fitted with K = 1.94 ± 0.09 and between 1963 and 1965 with K = 0.36 ± 0.05.


1969 ◽  
Vol 47 (19) ◽  
pp. 2051-2055 ◽  
Author(s):  
H. Carmichael ◽  
M. Bercovitch

This, the second paper of a set of five, describes a small latitude survey, made in Canada in December, 1965, while the intensity of cosmic radiation was still within one per cent of its IQSY maximum. Flat sites at airports were used in the hope of eliminating environmental effects noted in the 1965 summer survey and particular care was taken to verify the barometric data. The objective was to improve upon the summer measurements as regards the boundary of the high-latitude plateau of the neutron-monitor intensity and it is believed that an intrinsic accuracy within 0.1% was achieved, but it was found that the NM-64 neutron-monitor counting rate was decreased about 0.5% by the presence of snow on the ground. The intensity near sea level appeared to be constant to the southern boundary of the survey at Windsor Airport (1.56 GV). The two most southerly sites, Windsor and Toronto (1.33 GV), were snow-free.


2019 ◽  
Vol 5 (9) ◽  
pp. eaax3793 ◽  
Author(s):  
◽  
Q. An ◽  
R. Asfandiyarov ◽  
P. Azzarello ◽  
P. Bernardini ◽  
...  

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.


1978 ◽  
Vol 10 (4) ◽  
pp. 730-735
Author(s):  
H. S. Green

The theoretical analyses of the extensive air showers developing from the cosmic radiation has its origins in the work of Carlson and Oppenheimer (1937) and Bhabha and Heitler (1937), at a time when it was thought that such showers were initiated by electrons. The realization that protons and other nuclei were the primary particles led to a reformulation of the theory by Heitler and Janossy (1949), Messel and Green (1952) and others, in which the production of energetic pions and the three-dimensional development of air showers were accounted for. But as the soft (electromagnetic) component of the cosmic radiation is the most prominent feature of air showers at sea level, there has been a sustained interest in the theory of this component. Most of the more recent work, such as that by Butcher and Messel (1960) and Thielheim and Zöllner (1972) has relied on computer simulation; but this method has disadvantages in terms of accuracy and presentation of results, especially where a simultaneous analysis of the development of air showers in terms of several physical variables is required. This is so for instance when the time of arrival is one of the variables. Moyal (1956) played an important part in the analytical formulation of a stochastic theory of cosmic ray showers, with time as an explicit variable, and it is essentially this approach which will be adopted in the following. The actual distribution of arrival times is cosmic ray showers, for which results are obtained, is of current experimental interest (McDonald, Clay and Prescott (1977)).


2019 ◽  
Vol 5 (3) ◽  
pp. 54-58
Author(s):  
Анна Луковникова ◽  
Anna Lukovnikova ◽  
Виктор Алешков ◽  
Viktor Aleshkov ◽  
Алексей Лысак ◽  
...  

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.


Results are presented of an experiment to study the penetrating particles in the cosmic radiation deep underground, at a depth of 7500 m. w. e. (standard rock). The events recorded are attributable, in the main, to muons produced either in the atmosphere or by the interactions of neutrinos in the surrounding rock. The muons have been studied in some detail and it appears that the mean energy of the neutrino induced muons (probably less than about 30 GeV) is low compared with that of the muons of atmospheric origin. The significance of the celestial coordinates of the muons and the measured rate of neutrino- induced muons is discussed and the future experimental programme is indicated.


2020 ◽  
pp. 655-710
Author(s):  
Hermann Kolanoski ◽  
Norbert Wermes

Astroparticle physics deals with the investigation of cosmic radiation using similar detection methods as in particle physics, however, mostly with quite different detector arrangements. In this chapter the detection principles for the different radiation types with cosmic origin are presented, this includes charged particles, gamma radiation, neutrinos and possibly existing Dark Matter. In the case of neutrinos also experiments at accelerators and reactors are included. Examples, which are typical for the different areas, are given for detectors and their properties. For cosmic ray detection apparatuses are deployed above the atmosphere with balloons or satellites or on the ground using the atmosphere as calorimeter in which high-energy cosmic rays develop showers or in underground areas including in water and ice.


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