The CALorimetric Electron Telescope (CALET) space experiment, which has been developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission on the International Space Station (ISS). The primary goals of the CALET mission include investigating possible nearby sources of high energy electrons, studying the details of acceleration andpropagation of galactic cosmic rays, and searching for dark matter signatures. During an expected five-year mission, the CALET experiment is measuring the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV. CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. Since the start of operation at the ISS from mid-October, 2015, a continuous observation has been maintained mainly by triggering high energy (>10 GeV) showers without any major interruption. The number of the triggered events is about 20 million per month, and the number will reach to nearly one billion as of mid of July, 2019. By using the data obtained, we will have a summary of the CALET observations up to the recent period.

We are observing the very-high-energy radiations continuously come flying from space (cosmic rays) with the scintillation counter array located in Tibet highland, China at an altitude of 4,300 m. In this paper, we will explain the detection techniques of cosmic rays using the particle cascade in the atmosphere, so called “air shower”, and review the knowledge about cosmic-ray physics and the related field based on our observation results. Finally, we will introduce a new project of a cosmic ray experiment in the southern hemisphere.

The Telescope Array (TA) is the largest cosmic-ray detector in the Northern Hemisphere, constructed to study ultra-high-energy cosmic rays (UHECRs) with energies above approximately 10¹⁸ eV. The TA has also added a facility (TALE) to extend the energy threshold down to approximately 10¹⁶ eV, and also we are currently expanding the effective detection area to 3,000 km², which is called TA×4. The TA has accumulated a large UHECR data set which allows us to determine the energy spectrum and chemical composition of the primary particles, and search for anisotropy of UHECR arrival directions and thus sources of cosmic rays. We discuss the experiment and its most recent measurements - spectrum, composition, and anisotropy.

Four CTA (Cherenkov Telescope Array) Large Size Telescopes (LSTs) are under construction in Spain, La Palma. The CTA Large Size Telescope has a dish with a diameter of 23 m, and array of four CTA LSTs will have an order of magnitude better sensitivity in the energy range from 20GeV to 1TeV. We will discuss the status of the CTA International Gamma Ray Observatory and CTA-LSTs, and the science aimed with these telescopes.

The observations in MeV gamma-ray region from hundreds keV to tens MeV provide the important information about nucleosynthesis or particle acceleration, but it is not advanced comparing with those of the other bands. For opening the window of MeV gamma rays, we are developing an electron-tracking Compton camera which realizes the imaging spectroscopy based on a sharp point spread function. Our balloon experiments (SMILE: Sub-MeV/MeV gamma-ray Imaging Loaded-onballoon Experiments) verified that our ETCC can realize a high-sensitive observation. We then will start the scientific observations in a few years, and will open up the MeV gamma-ray astronomy.

We are developing GRAINE project, 10 MeV–100 GeV cosmic γ-ray observations with a precise (0.08 degree @1–2 GeV) and polarization sensitive large-aperture-area (～10 m²) emulsion telescope by repeating long duration balloon flights. An overview, status and prospect of our project are described.

Super-Kamiokande is a 50,000 ton water Cherenkov detector constructed 1,000 m underground in the Kamioka Mine, Gifu-prefecture, Japan. It started observation in 1996 and discovered neutrino oscillations through the observation of atmospheric neutrinos and solar neutrinos. At present, the detector is being upgraded for the detection of supernovae neutrinos from the beginning of our universe. In this article, achievements on neutrino oscillations and future prospects of Super-Kamiokande are described.

We observe solar neutrons (>100 MeV) on the ground to study the acceleration mechanism of high energy particles at the Sun. These neutrons are produced by the interaction between the accelerated ions and the solar atmosphere, and are observed on the ground without reflection by the interplanetary magnetic field. It is shown that the very efficient acceleration such as a shock acceleration does not work on the solar surface from the study of solar neutrons, if we assume these neutrons are produced at the same time as high energy electromagnetic waves. The determination of the efficiency of the acceleration without the assumption of the production of neutrons, is the final goal.