Subaru Users Meeting 2025
October 29 - 31, 2025 JST
Large Seminar Room, Mitaka Campus, National Astronomical Observatory of Japan (NAOJ)
Purpose
Thanks to the long-term efforts of the Subaru community and international collaborations, the Prime Focus Spectrograph (PFS) has begun science operations this spring, and a large amount of exciting observational data is now being delivered. For further success of the Subaru Telescope, we also need to promote the development of the ULTIMATE-Subaru, accelerate the synergistic observation with LSST and Roman, and innovate the observational technology via PI-type instruments development. As the situation surrounding Subaru changes dynamically every year, the annual Subaru Users Meeting is a vital opportunity for community members to gather, share the latest scientific results, understand the future outlook, and explore ways to collaborate. It is also an important opportunity for the observatory to receive feedback from the community, and to sophisticate the observatory's strategy toward the future, "Subaru 3". We encourage everyone in the Subaru community to participate in this users meeting, and join intensive, exciting discussions on various topics around the Subaru Telescope.
Registration
All participants to the Subaru Users Meeting 2025 require registration via Registration Form by the following dates.
| Due date | |
|---|---|
| Oral/Poster Presentation | Wednesday, September 24, 2025 (Closed) |
| Banquet on 10/30(Thu) | Wednesday, September 24, 2025 (Closed) |
| Travel support | Wednesday, September 24, 2025 (Closed) |
| On-site participation | Wednesday, October 15, 2025 |
| Online participation | Wednesday, October 22, 2025 |
(*) Zoom information will be provided for those who submit registration.
Handling of Personal Information
To organize the Subaru Users Meeting 2025, the organizing committee (subaru_um (at) naoj.org) collects your personal information, namely, your name, affiliation and e-mail address. We use your personal information only for organizing this meeting. We will keep some of your information until the next users meeting as a reference for it. By submitting the registration form, you agree that your personal data will be sent to the organizing committee and will be processed for the meeting organization.
Outline
| Meeting Title | Subaru Users Meeting 2025 |
| Date | Wednesday, October 29 to Friday, October 31, 2025 JST |
| Venue | Large Seminar Room, Mitaka Campus, National Astronomical Observatory of Japan (NAOJ) |
| Hosted by | Subaru Science Advisory Committee (SAC), and Subaru Telescope |
| Meeting Style | Hybrid On-site at the Mitaka Campus, and Online via Zoom ( *) Zoom information will be provided for those who submit registration. |
| Banquet | Thursday, October 30, at 6pm at the Large Seminar Room in the Mitaka Campus NAOJ |
| Organizing Committee | Masayuki Tanaka (NAOJ) Hirofumi Okita (NAOJ) Yuhei Takagi (NAOJ) Yuki Moritani (NAOJ) Itsuki Ogami (NAOJ) Tomoki Morokuma (Chiba Institute of Technology, SAC) Daisuke Iono (NAOJ, SAC) Mariko Kubo (Kwansei Gakuin University, SAC) |
(Tentative) Program
All date and time are in JST.
Day 1, 10/29(Wed)
| Time | Title | Speaker |
|---|---|---|
| 9:55-10:00 | Opening remark and announcement | |
| 10:00-11:40 | Reports from the Observatory | |
| 10:00-10:20 | Director's report | Satoshi Miyazaki |
| 10:20-10:35 | Science Operation Report FY2025 | Tae-Soo Pyo |
| 10:35-10:45 | Telescope Report | Yutaka Hayano (online) |
| 10:45-11:00 | Instrument Status | Takashi Hattori |
| 11:00-11:15 | ADC openuse services | Hisanori Furusawa |
| 11:15-11:30 | SAC report | Tomoki Morokuma |
| 11:30-11:40 | Okayama report | Akito Tajitsu |
| 11:40-12:10 | Poster flash talks | |
| 12:10-13:40 | Lunch & poster viewing | |
| 13:40-14:40 | Future instruments and collaborations 1 | |
| 13:40-14:10 | ULTIMATE | Yusei Koyama |
| 14:10-14:40 | Roman | Takahiro Sumi |
| 14:40-15:15 | Discussion 1 (Future instrument plan) (*) |
|
| 15:15-17:45 | Science talk 1 | |
| 15:15-15:30 | NINJA: Current Status of the NIR Spectrograph | Chihiro Tokoku |
| 15:30-15:45 | 16 HSC-Medium Band Filters | Atsushi J. Nishizawa |
| 15:45-16:00 | Break | |
| 16:00-16:15 | MAHALO Deep Survey: Environmental effects on star-forming galaxies in protoclusters at cosmic noon | Kazuki Daikuhara |
| 16:15-16:30 | The Nature of the Stellar Halo in the Andromeda Galaxy Explored with the Subaru/HSC | Itsuki Ogami |
| 16:30-16:45 | Carbon isotopologue ratio measurements of Hot Jupiter with IGRINS-2/Gemini-North | Yuya Hayashi |
| 16:45-17:00 | MOIRCS confirmation of super-Eddington accretion in an extremely X-ray loud radio quasar at z=3.4 in the eROSITA/eFEDS field |
Sakiko Obuchi |
| 17:00-17:15 | A status report of M31 eclipsing binaries survey for the distance measurement | Fumihiro Naokawa |
| 17:15-17:30 | Subaru Telescope and New Horizons: A Decade of Target Search, Recovery, and Results | Anne Verbiscer |
| 17:30-17:45 | A Joint Search for the EM Counterpart to the GW Binary Black Hole Merger Candidate S250328ae with DECam and PFS |
Haibin Zhang |
(*) primary in English. Japanese is OK.
Day 2, 10/30(Thu)
| Time | Title | Speaker |
|---|---|---|
| 9:00-10:15 | Report from Maunakea Observatories | |
| 9:00-9:15 | UH Institute for Astronomy Status and Future Plans | Doug Simon |
| 9:15-9:30 | Keck Observatory Update | Rich Matsuda (online) |
| 9:30-9:45 | Gemini Observatory Update | Atsuko Nitta |
| 9:45-10:00 | Canada-France-Hawai'i Telescope | Jean-Gabriel Cuby |
| 10:00-10:15 | TMT International Observatory | Fengchuan Liu (online) |
| 10:15-10:30 | Break | |
| 10:30-11:10 | TAC report and discussion (*) |
Takayuki Muto |
| 11:10-11:35 | Partnership program | |
| 11:10-11:15 | Introduction to Subaru partnership program | Yusei Koyama |
| 11:15-11:35 | New partner candidate: Scientific Interests of the Mexican Astrophysical Community with Subaru | Yair Krongold |
| 11:35-12:35 | Science talk 2 | |
| 11:35-11:50 | Framework Development for Numerical Modeling of the Low Wind Effect at Subaru | Márton Koren |
| 11:50-12:05 | [Th/Eu] ratios from the 5989 Å Thorium Line in the spectra of 36 Stars: constraints on r-process origins and galactic chemical evolution |
Kurumi Furutsuka |
| 12:05-12:20 | Resolving the Giant Lyα Emitters Himiko & CR7 at z=6.6 with JWST/NIRSpec IFU+Subaru/HSC+ALMA | Tomokazu Kiyota |
| 12:20-12:35 | New Horizons and FOSSIL HSC data and the LSST for Solar System Object discovery | JJ Kavelars |
| 12:35-14:00 | Lunch & poster viewing | |
| 14:00-14:30 | Future Instruments and collaborations 2 | |
| 14:00-14:30 | HWO | Olivier Guyon |
| 14:30-16:30 | Science talk 3 | |
| 14:30-14:45 | Synergies between Subaru Near-Infrared Surveys and NASA’s PRIMA Far-Infrared Mission | Hanae Inami |
| 14:45-15:00 | Multi-Wavelength High-Resolution Transmission Spectroscopy of KELT-20b with HDS, GRACES and IRD | Stevanus Kristianto Nugroho |
| 15:00-15:15 | The Extended Stellar Distribution in the Outskirts of the Ursa Minor Dwarf Spheroidal Galaxy | Kyosuke Sato |
| 15:15-15:30 | Cosmic Himalayas: The Highest QSO Density Peak at Cosmic Noon Bridging AGNs, Galaxies, and IGM | Yongming Liang |
| 15:30-15:45 | Break | |
| 15:45-16:00 | Status Report of WISHES+ (S24B-080QI) | Ken Osato |
| 16:00-16:15 | Current Status of Testing General Relativity with the Star Orbiting Galactic Center BH Sgr A* | Hiromi Saida |
| 16:15-16:30 | A Search for Dynamical Memory in the Spin Distribution of Galaxies in HSC WIDE Survey Regions | Masanori Iye |
| 16:30-17:45 | PFS session | |
| 15:30-16:55 | Instrument report | Shintaro Koshida |
| 16:55-17:45 | Discussions | Masayuki Tanaka |
| 18:30- | Banquet (Large Seminar Room @ Subaru building) |
(*) primary in English. Japanese is OK.
Day 3, 10/31(Fri)
| Time | Title | Speaker |
|---|---|---|
| 9:00-9:45 | Future Instruments and collaborations 3 | |
| 9:00-9:45 | LSST updates | Masamune Oguri, Yousuke Utsumi (online) |
| 9:45-11:00 | Science talk 4 | |
| 9:45-10:00 | Unveiling the Reionization Process through Subaru Intensive Program (S25A-047QI) | Rieko Momose |
| 10:00-10:15 | MIRACLES (S21A-114QI) | Yuichi Matsuda |
| 10:15-10:30 | Break | |
| 10:30-10:45 | IRD-SSP | Bunei Sato (online) |
| 10:45-11:00 | The Observing Accelerators with SCExAO Imaging Survey (OASIS): First Results (S24A-023I) | Thayne Currie (online) |
| 11:15-12:10 | Discussion 2 (PI-type Instruments, Proposal duplication) (*) |
|
| 12:10-13:40 | Lunch and poster viewing | |
| 13:40-15:10 | TMT-Subaru session (Japanese) | |
| 13:40 - 13:45 | Introduction | Fumi Yoshida |
| 13:45 - 14:05 | Star formation in the extreme outer Galaxy revealed by JWST and Subaru (English) | Natsuko Izumi |
| 14:05 - 14:15 | TMT-ACCESS report | Ryuji Suzuki |
| 14:15 - 14:35 | TMT progress report | Wako Aoki |
| 14:35 - 14:50 | Introduction and discussion of TMT science operations | Sakurako Okamoto (online) |
| 14:50 - 15:05 | TMT Strategic Development Research Expenses. Report and discussion of the survey results | Takayuki Kotani |
| 15:05 - 15:10 | Q&A | |
| 15:10-15:25 | Break | |
| 15:25-16:25 | Discussion 3 (Subaru 3)(Japanese) | |
| 16:25- | Closing remark |
(*) primary in English. Japanese is OK.
Posters
| No | Title | Author |
|---|---|---|
| P1 | PyIRD: A Python-Based Data Reduction Pipeline for Subaru/IRD and REACH, with Applications to Brown Dwarf Observations |
Yui Kasagi |
| P2 | Th/Eu abundance ratio of red giants in the Kepler field | Ainun Azhari |
| P3 | The Hyper Suprime-Cam Legacy Archive: Expanding Access to Science-Ready Data from 2014–2020 | Sumiko Harasawa |
| P4 | Novel Transmission Gratings with High-dispersion, High-efficiency and Wide Bandwidth II | Noboru Ebizuka |
| P5 | Search for long-period binary stars with compact objects | Ataru Tanikawa |
| P6 | Subaru/MOIRCS Wide-field Multi-object Spectroscopy of Very Low-mass objects in the R CrA region | Takahiro Kanai |
| P7 | Initial Analysis Results of Subaru/HSC Observations of TNOs for New Horizons Navigation Support | Neo Yamashita |
| P8 | Low-mass with high-SFR Hα emitters at z ~ 2 in ZFOURGE-COSMOS field | Jeung Yun |
| P9 | Instrument Performance verified through the PFS engineering observations | Yuki Moritani |
| P10 | Multi-Input Convolutional Neural Networks with Attention for Faint Moving Object Detection | Masato Shibukawa |
| P11 | Current status of DRP development for PFS | Kiyoto Yabe |
| P12 | The Origin of Phosphorus-rich Stars | Ryota Hatami |
| P13 | Unravelling star formation history in the Andromeda Galaxy halo(Subaru/HSC) | Tensho Ito |
| P14 | First Light of a Wide-Field, High-Speed CMOS Camera for the 90-Inch Telescope at Steward Observatory | Mihiro Takahashi |
| P15 | Star forming regions in the outer part of the dwarf irregular galaxy NGC 6822 | Sato Taiga |
| P16 | Progress and Challenges in Planning for Subaru PFS Open-Use Programs | Wanqiu He |
| P17 | Subaru Nasmyth Beam Switcher : commissioning status | Takashi Hattori |
| P18 | MIRACLES. Subaru HSC Ultra Deep Narrow-band Survey Data for Direct Detection of the Cosmic Web | Satoshi Yamanaka |
| P19 | Latest Report on Synergistic Observations with Subaru for the Nancy Grace Roman Space Telescope | Kazuki Daikuhara |
| P20 | Resurrection of Subaru+COMICS for the study of solar system objects with ground-based mid-infrared observations III |
Takafumi Ootsubo |
| P21 | Astrocomb and Fiber Feed Module for HDS | Masashi Omiya |
| P22 | Tech. IFU: Technology ferification for WFOS IFU | Shinobu Ozaki |
Banquet
The banquet will be held at the large seminar room at 6:30pm on 10/30(Thu).
The banquet fee will be collected at the registration of the meeting.
| Job Title | Fee |
|---|---|
| Professors, associate professors | 6,000 yen |
| Assistant professors | 5,000 yen |
| Postdocs | 4,000 yen |
| Students | 2,000 yen |
| Others | 5,000 yen |
Venue & Travel
The Subaru Users Meeting 2025 will be held with a hybrid stye, on-site in the Mitaka campus NAOJ and online via Zoom. The on-site meeting is at the large seminar room on the 1st floor of the Subaru building (Campus Map-W1) in the Mitaka campus, National Astronomical Observatory of Japan (NAOJ). Zoom information will be provided to the resgisterd participants.
We have a small budget to support your domestic travel (transportation and accommodation costs) for those who are affiliated with domestic organizations.
Unfortunately, there is no vacancy in the Cosmos Lodge (Campus Map-N1) in the Mitaka campus NAOJ at the time of writing this page.
Mitaka Campus NAOJ
Mitaka Campus, National Astronomical Observatory of Japan
2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
Access Information: ACCESS
Visitor Card Key (IMPORTANT)
NAOJ requires all visitors to register at the guard house (Campus Map-C1) upon their arrival. Please show your photo ID at the guard house next to the main gate. The organizing committee will submit pre-registation to the guard house so you only need to show your ID. A card key will be provided at the guard house, which you will need to enter buildings in the campus. You can keep the card key during the meeting (10/29-31), and return it to the guard house on the last day of your participation.
Code of Conduct
All attendees at the Subaru Users Meeting 2025 must agree to the NAOJ Code of Conduct.
Contact
If you have any questions, contact us at
subaru_um (at) naoj.org
Links
Last Update: October 9, 2025