News

LiteBIRD, a JAXA-led international space mission, has successfully passed Mission Definition Review #2.LiteBIRD aims to precisely measure the polarization of the cosmic microwave background and test the theory of cosmic inflation, which is thought to have occurred before the hot Big Bang.In this project, the Okayama University group has played a crucial role in connecting the scientific objectives with the detector development. To maximize the mission’s scientific return, the group has evaluated systematic effects that could limit observational performance and established a requirements flow-down framework for determining the design specifications of the instruments. These contributions also played a major role in the successful completion of this review.LiteBIRD will now proceed to the next phase, in which the team will further develop the detailed instrument design and advance data-analysis methods. Through these efforts, we will establish a framework for extracting the greatest possible scientific return from the data expected to be obtained by LiteBIRD.
For further details, please visit the Institute of Space and Astronautical Science website at the link below.
https://www.isas.jaxa.jp/missions/spacecraft/future/litebird.html

Ishino, Adachi, Takaku, Ikuma, and Ueyama participated in the workshop “Challenges at the CMB Frontier.” The workshop featured presentations and discussions by researchers from Japan and abroad on topics including CMB observations, data analysis, foreground removal, and instrumentation development.

Takaku gave an invited talk on the scientific goals and current development status of LiteBIRD, a satellite mission aimed at detecting primordial gravitational waves through observations of CMB polarization. Ikuma gave an oral presentation on a foreground removal method that incorporates prior distributions for the spectral parameters of foreground emission.

Ueyama presented a poster on a map-based simulation framework that models instrument-induced systematic effects in CMB polarization observations within spin space. Adachi gave an invited talk on the current status and future prospects of ground-based dark matter searches.

Through their participation in the workshop, the members had the opportunity to present their latest research results and engage in productive discussions with researchers from Japan and around the world.

Siméo Batt from Grenoble INP Phelma has arrived in Okayama as an internship student. He will stay in our laboratory for about three months, during which we will carry out research together.

Associate Professor Shunsuke Adachi of our laboratory gave an invited talk at the 7th International Symposium on Microwave/Terahertz Science and Applications (MTSA 2026). His talk, titled “Searching for Dark Matter with Broadband Millimeter-Wave Receivers,” introduced research on dark matter searches using millimeter-wave receivers.

Conference link: https://mtsa2026.riken.jp/index.html

On Monday, June 8, 2026, Assoc. Prof. Shunsuke Adachi (Graduate School of Environmental, Life, Natural Science and Technology, Okayama University) of our laboratory gave a presentation at the J-PEAKS Symposium “A New Quantum World, Green Energy, and Dark Matter Observation Opened Up by Superconductivity,” held at the 50th Anniversary Hall of Okayama University.

In Presentation 5 (16:50–17:20), Assoc. Prof. Adachi presented his latest research on dark matter searches using superconducting technology. Dark matter accounts for approximately 85% of all matter in the universe, yet its true nature remains unknown. He introduced a unique approach combining radio waves and superconductivity as a means of detecting this elusive substance.

URL: https://www.orsd.okayama-u.ac.jp/topics/j_peaks_symposium/

A research project on radio-wave-based dark matter searches led by Associate Professor Shunsuke Adachi has been selected as a new project for FY2025 under the Fusion Oriented REsearch for disruptive Science and Technology (FOREST) program of the Japan Science and Technology Agency (JST).

The project aims to explore the nature of dark matter using advanced radio-frequency measurement techniques. As part of this effort, the research team will develop a new superconducting parametric amplifier to further improve the sensitivity of dark matter searches. This advancement is expected to expand the accessible parameter space and enhance the potential for discovering previously unexplored dark matter candidates.

For more information on the FY2025 selected projects, please visit the JST website:

https://www.jst.go.jp/souhatsu/call/sel25.html

On April 6, 2026, we held a joint cherry blossom viewing event at Handayama botanical garden together with members of the Yamauchi Laboratory and Nagao Laboratory from Okayama University of Science.

Our new fourth-year students also participated, and while enjoying lunch and the cherry blossoms, we had a valuable opportunity to deepen our interactions with many people beyond the boundaries of our respective laboratories.

We hope to continue valuing these opportunities for interaction and further develop our research activities in the future.

We had welcome party for new members of our laboratry, Komori, Shigeno, Takahara and Tomokuni they have come to from this April, and Mahdi Najafi who is staying from this February. We gathered around the table as a group and were able to get to know the new members better. We hope this will serve as a catalyst for more active communication within the lab.

We are pleased to announce that Higuchi has completed the master’s program, and Fukushima, Ueyama, and Hattori have graduated from the undergraduate program in our laboratory. Higuchi will be joining a company, while Hattori will go on to graduate studies at another university. Fukushima and Ueyama will continue on to graduate school at Okayama University and remain in our laboratory to pursue their research. We sincerely commend all of them for their hard work and achievements, and we look forward to their continued success in the future. Congratulations to everyone.

From April 1 to 2, 2026, Mr. Ikuma (D2), Mr. Kakinoki (M2), Mr. Fukushima (M1), and Ms. Ueyama (M1) gave presentations at the Post-C2C Meeting held at Tokyo Midtown Yaesu.

This meeting was organized to strengthen collaboration within the CMB research community in Japan, building on the achievements of the “CMB Core-to-Core Program” conducted from 2020 to 2024. The event also provided valuable opportunities to interact with researchers from various institutions, making it a highly meaningful experience.