Ongoing Research and Preliminary Findings

Many cosmic rays are absorbed by the atmosphere, and it is well known that the number of observed cosmic rays increases with altitude. Utilizing this phenomenon, we are conducting experiments at higher altitudes to confirm that cosmic rays can indeed be detected using CMOS camera image sensors.

We prepared a detector similar to the one shown on the left and conducted experiments on an airplane. A CMOS sensor is connected to a Raspberry Pi, and the white device is a GPS housed in a waterproof box. The flight routes consist of three options: Guam, Vancouver, and Montreal, all flying to Japan. As shown in the color-coded diagram, there is a significant difference in cutoff rigidity due to the magnetic field for the Guam route. Therefore, if observations are successful, we anticipate a noticeable difference in the increase in observation amounts.

The three figures below represent actual observation results. The shaded areas indicate the average signal levels and standard deviations from ground observations. In the Guam route, we have extracted the time periods with sufficiently increased observation levels, displaying the average and standard deviation. From this, we can see an increase of 3.54 times compared to ground levels. Similarly, the Vancouver route shows a 4.24 times increase, while the Montreal route shows a 5.25 times increase. As predicted, the Guam route, which experiences the strongest cutoff due to the magnetic field, has the least increase.

Preliminary
Preliminary
Preliminary

Other comparative Measurements

Peer-reviewed papers

  • Development of a Smartphone-Based Radiation Detection App and Its Application to Science Education Outreach: New Possibilities for Science Education Through a Cosmic Ray Detection App Wakiko Takano, Kinya Hibino, Shigeharu Udo CIEC Spring Conference 2025 Proceedings Vol.16, p.23.

Conference Presentations

  • October 27, 2025 30th IPPOG meeting @CERN
    SORAMAME: Scientific Observation & Research on Astroparticles—Anywhere, by Anyone Wakiko Takano Presentation slide
  • September 16, 2025 The 80th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors (6)
  • July 14–24, 2025 The 39th International Cosmic Ray Conference (ICRC2025) in Geneva, Switzerland
    Development of a Smartphone-Based Radiation Detection App and Its Application to Science Education Outreach – New Possibilities for Science Education Through a Cosmic Ray Detection App Wakiko Takano, Kinya Hibino, Shigeharu Udo, Atsushi Shiomi PoS ICRC2025 (2025) 1255
  • September 18, 2024 The 79th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors (5)
  • September 16, 2023 The 78th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors (4)
  • July 29 – August 2, 2023 The 38th International Cosmic Ray Conference (ICRC2023) at NAGOYA
    A New Method for Observing the Core of the Highest Energy Cosmic Rays Using Compact Detectors. W. Takano and K. Hibino PoS(ICRC2023)410
    Consumer Devices with CMOS camera image sensors as Pocket-Sized Particle Detectors. W. Takano and K. Hibino PoS(ICRC2023)1620
  • March 27, 2023 The 6th Workshop on Exploration of Cosmic Ray Origin by Air Shower Observation
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors - Proposal of a Simple Observation Model Performing Observations with Three CMOS Sensors as an Array and iOS App 'Soramame'
  • September 6–8, 2022 The 77th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors (3)
  • July 15–22, 2021 The 37th International Cosmic Ray Conference
    Observing Ultra-High Energy Cosmic Rays EAS Core using CMOS Camera Image Sensors
  • March 12–15, 2021 The 76th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors (2)
  • November 9–13, 2020 The Association of Asia Pacific Physical Societies - Division of Astrophysics, Cosmology and Gravitation, Workshop on Astrophysics, Cosmology and Gravitation
    Observing Ultra-High Energy Cosmic Rays EAS Core using CMOS Camera Image Sensors
  • September 14–17, 2020 The 75th Annual Meeting of the Physical Society of Japan
    Observations of Ultra High-Energy Cosmic Ray Air Showers using CMOS Camera Image Sensors