We present the main characteristics of cosmic ray population in the atmosphere and its variability (11-and 22-year solar cycle variations, solar protons originating from powerful solar flares, energetic electron precipitation during geomagnetic disturbances and Forbush decreases of cosmic rays). The experimental data were obtained from the long-term cosmic ray monitoring in the atmosphere from ...

Via its role in aerosol formation, cosmic ray may affect the global cloudiness and hence climate. Here we show that an increase in cosmic ray fluxes may lead to an increase in particle production in the lower troposphere but a decrease in particle production in the upper troposphere. In addition to the reported positive correlation between cosmic ray variations and low cloudiness, our analysis ...

The solar wind modulates the flux of galactic cosmic rays impinging on Earth inversely with solar activity. Cosmic ray ionisation is the major source of air’s electrical conductivity over the oceans and well above the continents. Differential solar modulation of the cosmic ray energy spectrum modifies the cosmic ray ionisation at different latitudes, varying the total atmospheric columnar condu...

We report new high resolution measurements of the elemental and isotopic composition of galactic cosmic ray B, C, N, and 0 nuclei with ~ 30 to ~ 130 MeV nucleon-•. These observations place limits on the isotopic composition of the cosmic ray source and restrict possible models of cosmic ray origin and propagation. In particular, we find that N is significantly depleted in the cosmic ray source ...

In this study, we aimed to measure the directly ionizing component (muons and photons) and the indirectly ionizing component (neutrons) of the cosmic-ray spectra and evaluate their dose rate contribution to the total dose rate on a ground level in Japan. Measurements were carried out in Tohoku University, Japan, from October 2000. The pulse-height spectra of the cosmic-ray photons and muons wer...

Study of cosmic ray became a subject of study with the invention of neutron monitor by Simpson. But recording of cosmic ray counts was started regularly from International Geophysical Year at different locations having different climatic zones over the globe. Here statistical analysis is performed to investigate the degree of response of different monitors towards cosmic ray counts. No signific...

We show that the expected composition of cosmic rays accelerated from the erosion products of fast supernova grains in the hot interstellar medium (HISM) of ejecta enriched superbubbles, where the bulk ( 85%) of Galactic supernovae occur, is consistent with the currently available cosmic ray data. In particular, we show that if the cosmic ray metals come from the sputtering of fast refractory g...

Centaurus A, the cosmic ray accelerator a few Mpc away from us is possibly one of the nearest sources of extremely high energy cosmic rays. We investigate whether the gamma ray data currently available from Centaurus A in the GeV-TeV energy band can be explained with only proton proton interactions. We show that for a single power law proton spectrum, mechanisms of γ-ray production other than p...

Centaurus A, the cosmic ray accelerator a few Mpc away from us is possibly one of the nearest sources of extremely high energy cosmic rays. We investigate whether the gamma ray data currently available from Centaurus A in the GeV-TeV energy band can be explained with only proton proton interactions. We show that for a single power law proton spectrum, mechanisms of γ-ray production other than p...