scholarly journals Cosmic-Ray Experiments at High Altitudes over a Wide Range of Latitudes

1949 ◽  
Vol 76 (7) ◽  
pp. 914-932 ◽  
Author(s):  
A. T. Biehl ◽  
H. V. Neher ◽  
W. C. Roesch
Keyword(s):  
2021 ◽  
Author(s):  
Jannis Weimar ◽  
Paul Schattan ◽  
Martin Schrön ◽  
Markus Köhli ◽  
Rebecca Gugerli ◽  
...  

<p><span>Secondary cosmic-ray neutrons may be effectively used as a proxy for environmental hydrogen content at the hectare scale. These neutrons are generated mostly in the upper layers of the atmosphere within particle showers induced by galactic cosmic rays and other secondary particles. Below 15 km altitude their intensity declines as primary cosmic rays become less abundant and the generated neutrons are attenuated by the atmospheric air. At the earth surface, the intensity of secondary cosmic-ray neutrons heavily depends on their attenuation within the atmosphere, i.e. the amount of air the neutrons and their precursors pass through. Local atmospheric pressure measurements present an effective means to account for the varying neutron attenuation potential of the atmospheric air column above the neutron sensor. Pressure variations possess the second largest impact on the above-ground epithermal neutron intensity. Thus, using epithermal neutrons to infer environmental hydrogen content requires precise knowledge on how to correct for atmospheric pressure changes.</span></p><p><span>We conducted several short-term field experiments in saturated environments and at different altitudes, i.e. different pressure states to observe the neutron intensity pressure relation over a wide range of pressure values. Moreover, we used long-term measurements above glaciers in order to monitor the local dependence of neutron intensities and pressure in a pressure range typically found in Cosmic-Ray Neutron Sensing. The results are presented along with a broad Monte Carlo simulation campaign using MCNP 6. In these simulations, primary cosmic rays are released above the earth atmosphere at different cut-off rigidities capturing the whole evolution of cosmic-ray neutrons from generation to attenuation and annihilation. The simulated and experimentally derived pressure relation of cosmic-ray neutrons is compared to those of similar studies and assessed in the light of an appropriate atmospheric pressure correction for Cosmic-Ray Neutron Sensing.</span></p>


2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Jacob Oloketuyi ◽  
Yu Liu ◽  
Amobichukwu Chukwudi Amanambu ◽  
Mingyu Zhao

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.


2019 ◽  
Vol 208 ◽  
pp. 08006
Author(s):  
R.P. Kokoulin ◽  
N.S. Barbashina ◽  
A.G. Bogdanov ◽  
S.S. Khokhlov ◽  
V.A. Khomyakov ◽  
...  

An experiment on the measurements of the energy deposit of inclined cosmic ray muon bundles is being conducted at the experimental complex NEVOD (MEPhI). The complex includes the Cherenkov water calorimeter with a volume of 2000 m3 and the coordinate-tracking detector DECOR with a total area of 70 m2. The DECOR data are used to determine the local muon densities in the bundle events and their arrival directions, while the energy deposits (and hence the average muon energy loss) are evaluated from the Cherenkov calorimeter response. Average energy loss carries information about the mean muon energy in the bundles. The detection of the bundles in a wide range of muon multiplicities and zenith angles gives the opportunity to explore the energy range of primary cosmic ray particles from about 10 to 1000 PeV in the frame of a single experiment with a relatively small compact setup. Experimental results on the dependence of the muon bundle energy deposit on the zenith angle and the local muon density are presented and compared with expectations based on simulations of the EAS muon component with the CORSIKA code.


1989 ◽  
Vol 120 ◽  
pp. 32-37
Author(s):  
R. Gredel ◽  
S. Lepp ◽  
A. Dalgarno ◽  
E. Herbst

AbstractUltraviolet photons are created in the interior of dense interstellar clouds by the impact excitation of molecular hydrogen by secondary electrons generated by cosmic ray ionization. The resulting photodissociation and photoionization rates of a wide range of interstellar molecules are calculated. The effects on the equilibrium chemical composition of dense clouds are briefly discussed.


2019 ◽  
Vol 208 ◽  
pp. 14008
Author(s):  
V.G. Sinitsyna ◽  
V.Y. Sinitsyna

Cygnus X-3 binary system is a famous object studied over the wide range of electromagnetic spectrum. Early detections of ultra-high energy gamma-rays from Cygnus X-3 by Kiel, Havera Park and then by Akeno triggered the construction of several large air shower detectors. Also, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of twenty-year observations of the Cyg X-3 binary at energies 800 GeV - 85 TeV are presented with images, spectra during periods of flaring activity and at low flux periods. The correlation of TeV flux increases with flaring activity at the lower energy range of X-ray and radio emission from the relativistic jets of Cygnus X-3 is found as well as 4.8-hour orbital modulation of TeV γ-ray intensity. Detected modulation of TeV γ-ray emission with orbit and important characteristics of Cyg X-3 such as the high luminosity of the companion star and the close orbit leads to an efficient generation of γ-ray emission through inverse Compton scattering in this object. The different type variability of very high-energy γ-emission and correlation of radiation activity in the wide energy range can provide essential information on the mechanism of particle production up to very high energies.


1934 ◽  
Vol 45 (7) ◽  
pp. 441-450 ◽  
Author(s):  
A. H. Compton ◽  
R. J. Stephenson
Keyword(s):  

2014 ◽  
Vol 357 ◽  
pp. 217-243
Author(s):  
R.H. Biswas

Luminescence, mainly thermoluminescence (TL) and optically stimulated luminescence (OSL), has been researched for more than five decades towards its application to earth and planetary sciences. Luminescence production mechanism has been understood through several theoretical studies, like analytical kinetic theory, numerical models along with the experimental results. Instrument development has progressed with aim from user friendly TL/OSL reader dedicated for dating to challenging reader forin-situMartian sediment dating. Since the development of optical dating in 1985, the technique revolutionised the research in earth sciences. And since then to recent, many methodologies have been developed and some are in developing stage using different signals, like, single grain OSL, red TL, time resolved OSL, thermally transferred OSL (TT-OSL), post infrared-infrared stimulated luminescence (pIR-IRSL), violet light stimulated luminescence (VSL), infrared radioluminescence (IRRL), etc. with an objective to improve the accuracy and precision and to extend the dating range. The wide range of application in different environment, e.g. aeolian, fluvial, marine, glacier, soil, volcanic materials, heated materials, shocked materials, meteorites, etc. have made the technique successful to understand the quaternary history of earth and planetary information like terrestrial and cosmic ray exposure ages of meteorite, meteoroid orbit, thermal metamorphism history of meteorite etc. The aim of this present paper is to discuss some landmarks and recent trends in the development and application in these areas. Contents of the Paper


1948 ◽  
Vol 20 (1) ◽  
pp. 360-366 ◽  
Author(s):  
A. T. Biehl ◽  
R. A. Montgomery ◽  
H. V. Neher ◽  
W. H. Pickering ◽  
W. C. Roesch

2020 ◽  
Author(s):  
Paul Connell

<p>In designing the MXGS coded mask imager on the ASIM mission to the ISS many simulations of its performance were made using a model of TGF origin as a RREA in a vertical electric ffield at about 15 km altitude. One consequence was the prediction that imaging scatter background from high energy photons would be 15-20% of CZT detector counts, decreasing with TGF off-axis observation angle.</p><p>Analysis of the linear image reconstruction model shows the maximum scatter background to be 40% in some cases, with sources at the same off-axis angle having both small and large scatter background. The obvious reason to explain this asymmetry is that a TGF beam is not primarily vertical, but at large angles, and provokes an inference about TGF origin.</p><p>The phenomenon can be explained by TGF origin at the tips of lightning leader channels, resulting in a wide range of random beam angles, or in the macro electric ffield of the induced negative shfielding charge above a stormcloud. This charge might begin as concentrated near the top-centre of a stormcloud but should slowly spread out to form a torus-like charge with the greatest electric field on the circular boundary of the torus, over a range of angles from vertical to horizontal to downward - with many TGFs absorbed or expanding spherically as a low energy Compton Scatter Remant.</p><p>In this scenario the TGF would originate near the upper radial edge of the cloud, but not within it, either by lightning leader electron injection or electron positron injection from a cosmic ray shower, posing the question if this location of origin can be observed.</p><p>We made a study of over 6000 TGF locations from FERMI-WWLLN observations where the centroid centrepoint of the nearest lightning cluster to the TGF was located, allowing for wind drift, its RMSQ cluster radius determined, and its distance vector from the cluster centrepoint. If the cluster would represent stormcloud location and area, then the macro E-field scenario of TGF origin should result in an annular distribution of the TGF-WWLLN vector location, but convolved with the lightning location error distribution. We present the results here, showing there is indeed a significant increase in TGF origin at the outer boundary of stormcloud lightning clusters.</p>


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