Toward clarification of the History of the Universe
Why our Universe was bone and how it developed into the present state? Since its birth at the Big Bang, the Universe has experienced various drastic events. Because the Universe is not a stable object, we have to understand and explain the present state as a consequence of dynamical processes the Universe has experienced. Though many events in the History of the Universe have been clarified, many pieces are still missing to understand our Universe today.
Tomonaga Center for the History of the Universe (TCHoU) was founded in October 2017 as a research center at the University of Tsukuba. The mission of the Center is to clarify the genesis of the Universe as well as the origin of matter and life and to construct an integrated view of the History of the Universe, through international and interdisciplinary collaboration of particle, nuclear, and astrophysics as well as resonant cooperation of experimental and theoretical approaches.
Toward this goal, the center has established the following four research divisions:
- Division of Antarctic Astronomy
- Division of Elementary Particles
- Division of Quark Nuclear Matters
- Division of Photon and Particle Detectors
Please visit
♠
[About the Center] for an overview of the Center.
♦
[Projects] for the research projects of the Center.
♥
[Organization] for the organization and members of the Center.
♣
[Materials] for reports and introductory materials.
The name Tomonaga Center comes from Dr. Sin-Itiro Tomonaga, the second Nobel Laureate from Japan, who made fundamental contributions in constructing relativistic quantum field theories, the renormalization theory, theory of collective motions, etc. and also a founder of the physics institute at Tsukuba.
Visit Tomonaga Memorial Room, Univ. Tsukuba and Tomonaga Exibition at the University of Tsukuba Gallery for more information about Dr. Tomonaga.
(Photo: Tomonaga Memorial Room)
What's new
- 2024/10/04 HoU seminar
- Date： Oct. 04, 2024 (Fri) 13:45-15:00
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- Speaker: Keita Mizukoshi (JAXA/ISAS)
- Title: "Search for dark matter using a long-duration orbiting balloon in Antarctic'"
- Despite the evidence for dark matter as an unknown particle inferred from astronomical observations, its true nature remains elusive. While direct searches using xenon dual-phase detectors have yielded significant results, they are approaching the detection limit due to neutrino background events. On the other hand, indirect detection experiments are crucial as they can directly test the thermal production model of dark matter, making them complementary to other search methods. Additionally, cosmic antiparticles (such as antiprotons) originating from dark matter are expected to allow background-free searches in the low-energy region, meaning that the detection of even a single antiproton could provide critical information about the nature of dark matter.
The GAPS experiment plans to conduct its search in the upper stratosphere over Antarctica using a helium balloon, in order to avoid the effects of the atmosphere and geomagnetism. A flight lasting about one month, carrying a payload of approximately 2 tons equipped with a silicon detector array and TOF scintillators, is scheduled for this December. In this seminar, we will provide a detailed explanation of the indirect detection of dark matter, the GAPS experiment, and the unique aspects of balloon experiments. - Number of participants: 25
Contact: Assi.Prof. T. Iida
- 2024/09/30 Tsukuba Global Science Week (TGSW) 2024 "Universe Evolution and Matter Origin"
As the Session 4-1 of the Tsukuba Global Science Week, TCHoU is organizing the International Workshop on "Universe Evolution and Matter Origin" as an on-line workshop.
Registration is free. Please register via TGSW web-site to receive the connection information.
Session program will be announced in the Session web-site soon.
- Date: Sept.30, 2024 (Mon) 15:00-21:00
- Venue: Online
- URL: TGSW : Session 4-1 "Universe Evolution and Matter Origin"
Contact: Prof. Akira Ozawa
- 2024/09/23 HoU seminar
- Date： Sept. 23, 2024 (Fri) 11:00-
- Venue: 1F201, !st Cluster Bldg. 1F, Univ. Tsukuba / Zoom
- Speaker: Nu Xu (LBNL/IMP)
- Title: "Study of the QCD Phase Structure - Recent Results from RHIC Beam Energy Scan Program"
Contact: Prof. S. Esumi
- 2024/08/30 HoU seminar
- Date： Aug. 30, 2024 (Fri) 13:45-15:00
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- Speaker: Hiroshi IMAI (Kagoshima University)
- Title: "On the 'Stellar Water Fountains/Geysers'"
- Number of participants: 20
Contact: Prof. N. Kuno
- 2024/07/12 HoU seminar
- Date： Jan. 19, 2024 (fri) 13:45-15:00
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- Speaker: Ashutosh KOTWAL (Duke University, USA)
- Title: "High-precision measurement of the W boson mass with the CDF II detecto"
- The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, MW, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 TeV center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain MW=80,433.5 ± 6.4 (stat) ± 6.9 (syst) = 80,433.5 ± 9.4 MeV/c2, the precision of which exceeds that of all previous measurements combined. This measurement is in significant tension with the standard model expectation.
Contact: Prof. F. Ukegawa
- 2024/07/06 Tanabata Lecture of Astronomy
Lectures by astronomers will be held near Tanabata Day. The state-of-the-art research content will be explained in an easy-to-understand manner to the general public. (in Japanese)
Click on the poster for details.
- Date： 6 July (Saturday) 13:30－16:30
- Venue: Tsukuba International Congress Center EPOCHAL, Conference room 101
- Program:
13:30- Koji Yoshikawa (Univ. Tsukuba) Supercomputer "Fugaku" × Large-scale structure of the universe × Neutrinos 15:00- Nario Kuno (Univ. Tsukuba) Let's take a radio telescope to Antarctica! -- In search of the best sky on earth 16:30 End - Target: General public (junior high school students and above)
- Participation fee: Free
Contact: Prof. N. Kuno (TEL: 029-853-5080)
- 2024/07/14 Assi. Prof. Hashimoto made a press release on Bound star clusters 460 Myr after the Big Bang
Assistant Professor Takuya Hashimoto (Division of the Antarctic Astronomy) held a press conference on ”Bound star clusters observed in a lensed galaxy 460 Myr after the Big Bang”, published in Nature, DOI: 10.1038/s41586-024-07703-7.
For more details, see the press release article and a web announcement of the Univ. of Tsukuba.
- 2024/07/02 TCHoU Research Member Meeting / Activity and Achievement Reports
We have a research workshop to share achievements, exchanging activities and future projects for all members of TCHoU.
After the workshop, we have a get-together at Yasei-no-Mori. Please contact Assi.Prof. T. Iida for details.
- Date: 2 June 2023 (Tu) 9:30-17:10
- Venue: Natural Science Bldg. B114
- Program: (presentations are given mostly in Japanese)
- Click on the title for presentation slides.
Contact: Prof. F. Ukegawa
- 2024/04/21 Kids' University
At the Kids' University, Science and Technology Week, University of Tsukuba, we presented an exhibition "Pursuit of the History of the Universe" for children.
- Date: April 21 (Sun) 13：00-17：00
- Venue: B118, Bldg. Sogo-B, Univ. Tsukuba
- Admission free
- Number of participants: about 300 (incl. children: about 200)
Contact: Prof. F. Ukegawa
- 2024/04/16 Member list and pamphlet of TCHoU have been updated.
- 2024/04/01 Frof. F. Ukegawa took the director of the TCHoU, and Prof. N. Kuno, the former director of TCHoU, assumed the vise dirctor of the TCHoU.
- 2024/03/29 Workshop by the Division of Quark Nuclear Matters
We held the Workshop at the Tomonaga Center for the History of the Universe (TCHoU) in our research division for Quark-Nuclear Matters on 29/Mar/2024 (Fri) afternoon by having presentations directly related to our projects according to the following agenda program of this workshop, we would like to invite and encourage all of you to join and have active discussions in the workshop. We will have this workshop with "in-person" participation at Univ. of Tsukuba, but we will have online zoom connection as indicated in the following. So I hope to see you all in Tsukuba, but even if you will not be able to come to Tsukuba, you could still participate in online.
Thank you very much for your active participations in terms of both giving the presentations and participating in the discussions in advance and for our future fruitful cooperation and collaboration.
- Date: March 29 (Fri), 2024 13:00-16:30
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- zoom: https://us02web.zoom.us/j/87227754233?pwd=VUFzS2p4d000MjRDWXpqemlaZ2VoZz09
- Program:
-
13:00‐ Fan Si (USTC/U. Tsukuba) Fluctuation analysis in STAR-BES2 13:30- TadaAki Isobe (RIKEN) Experimental study of asymmetric nuclear matter EOS from heavy-ion reactions with RIBF-SPiRIT 14:00- Tetsuaki Moriguchi (U. Tsukuba) Reaction cross sections for proton-drip line nuclei 14:30‐15:00 coffee 15:00- Tatsuya Chujo (U. Tsukuba) ALICE FoCal and eIC 15:30- Daiki Sekihata (U. Tokyo) ALICE Run3 and ALICE3 16:00- Yorito Yamaguchi (Hiroshima U.) RHIC & LHC to FAIR - Number of participants: about 20
Contact: Asso.Prof. S. Esumi
- 2024/03/15 Workshop by the Division of Elementary Particles
TCHoU Workshop of AY 2023 on Particle Physics, organized by the Division of Elementary Particles, is held as follows. This workshop is free to access. Talks are given in Japanese.
- Date: March 15 (Fri), 2024 13:30-18:00
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- Program:
Contact: Asso.Prof. Y. Takeuchi
- 2024/02/01 Assi. Prof. Hashimoto made a press release on Molecular outflow in the reionization-epoch quasar
Assistant Professor Takuya Hashimoto (Division of the Antarctic Astronomy) held a press conference on ”Molecular outflow in the reionization-epoch quasar J2054-0005 revealed by OH 119 μm observations”, published in The Astrophysical Journal, DOI: 10.3847/1538-4357/ad0df5..
For more details, see the press release article and a web announcement of the Univ. of Tsukuba.
- 2024/01/19 HoU seminar
- Date： Jan. 19, 2024 (fri) 13:15-15:30
- Venue: B118, Natural Sci. Bldg. B, Univ. Tsukuba
- Speaker1: Tsutomu Mibe (KEK, Inst. Particle and Nuclear Studies)
- Title1: "Achievement through cooling and acceleration! New Experiment to Accurately Measure Muon g-2 and EDM"
- The anomalous magnetic moment (g-2) and electric dipole moment (EDM) of muons are powerful means of studying unknown particle physics laws, as they can manifest physics phenomena beyond the Standard Model through quantum effects. In conventional measurement methods, the quality of the muon beam constitutes a significant systematic error, and there is a demand to improve this for the next-generation experiments significantly. We have achieved an extremely low emittance "ultracold muon beam" by cooling and accelerating muons, introducing a new experimental approach that eliminates traditional limitations. This allows for the precise measurement of the anomalous magnetic moment (g-2) and electric dipole moment (EDM) of muons. In this seminar, we will provide an overview of the recent developments surrounding g-2 and introduce the preparation status of the experiment.
- Speaker2: Takayuki Yamazaki (KEK, Inst. Particle and Nuclear Studies)
- Title2: "The Past and Future of the J-PARC Muon H-Line"
- At the J-PARC high-intensity proton accelerator facility in Tokai Village, Ibaraki Prefecture, a high-intensity proton beam with an energy of 3 GeV and a beam power of 1 MW is irradiated onto a graphite target. The muons generated by the decay of charged pions produced in nuclear fragmentation reactions are utilized for a wide range of research, spanning from material science to particle physics. The J-PARC Muon Science Experimental Facility, which started operating its first beamline (D-line) in September 2008, expanded with the addition of the U-line in 2012, the S-line in 2017, and the H-line in 2022, each providing distinct muon beams. The H-line introduced in this seminar is a beamline where the world's highest-intensity positive and negative pulse muons are available. In the experimental area at the first branching point (H1 area), fundamental physics experiments requiring high-intensity muon beams, such as precision spectroscopy of muonium (a hydrogen-like atom composed of a positive muon and an electron) and exploration experiments of muon-electron conversion processes, are conducted. Furthermore, the construction of the second branching point in the H-line is underway to generate an "ultracold muon beam" with extremely low emittance through muon cooling and reacceleration. This ultracold muon beam is not only applicable to muon g-2/EDM experiments but is also used in the transmission-type muon microscope (TμM), enabling the observation of thick samples. In this seminar, we will provide an overview of the J-PARC Muon H-line, its construction history, and prospects for the future.
- Number of participants: on-site 17 + online 6
Contact: Assi.Prof. T. Iida
- Visit [Archive] for previous news and announcements.
