Osaka-Hamburg Symposium on Quantum Science 2025

18 Feb 2025, 00:00 → 19 Feb 2025, 22:00 Europe/Berlin

CFEL at DESY campus (and https://uni-hamburg.zoom.us/j/67526723307?pwd=Kbs8rLvZ89wu5ICHaHfnbSEeDc5V61.1)

Theresa Staufer, Thore Posske (Universität Hamburg)

We are organizing the 2-day Osaka-Hamburg Symposium 2025 to initiate the future research collaboration between the Osaka University in Japan and University of Hamburg in Germany.

The event is part of the Osaka University's Pioneering Quantum Beam Application (PQBA) doctoral program. Any subject relevant to quantum science is welcome, and we look forward to the valuable insights and discussions that will contribute to the advancement of quantum beam research.

Subjects

The following subjects will be introduced as research areas of invited speakers:

1. Targeted alpha therapy and diagnostics
2. Radiation therapy
3. Infectious diseases
4. High energy and nuclear physics
5. Computational high energy physics
6. Condensed matter physics

In addition to these topics, student presentations will cover a wide range of other areas related to quantum science, ensuring a diverse and comprehensive exploration of the field.
We are excited to see a wide range of topics related to quantum science and anticipate fruitful discussions that will drive future innovations.

flyer_OHS2025.pdf

Tuesday 18 February

09:00 → 09:05 Opening address UHH - Prof. Wolfgang Hillert, Vice Dean for Internationalization, Faculty of Mathematics, Informatics and Natural Sciences (MIN) at University of Hamburg

Prof. Wolfgang Hillert (Vice Dean)

09:05 → 09:10 Opening address Osaka - Prof. Takashi Nakano, Director, Research Center for Nuclear Physics (RCNP) at Osaka University

Prof. Nakano

09:20 → 09:50 Keynote 1 - Targeted alpha therapy and diagnostics: "Targeted alpha therapy" (Prof. Koichi Fukase, Osaka University) - Chair person: Prof. Masaharu Nomachi

Targeted alpha therapy (Prof. Fukase, Chemistry)

09:50 → 10:20 Keynote 2 - Targeted alpha therapy and diagnostics: "X-ray fluorescence imaging as a tool to monitor gold nanoparticle distributions in targeted alpha therapy" (Prof. Florian Grüner, University of Hamburg) - Chair person: Prof. Masaharu Nomachi

"X-ray fluorescence imaging as a tool to monitor gold nanoparticle distributions in targeted alpha therapy" (Prof. Florian Grüner, University of Hamburg)

XFI_Osaka-Smposium_Grüner.pdf

10:20 → 10:55 Keynote 3 - Radiation Therapy: "Cellular Responses on Ultra-High Dose Rate Irradiation" (Prof. Kazumasa Minami, Osaka University) - Chair person: Prof. Masaharu Nomachi

Cellular Responses on Ultra-High Dose Rate Irradiation (Prof. Kazumasa Minami, Radiation Therapy)

10:55 → 11:05 Break

11:05 → 11:40 Keynote 4 - Radiation Therapy: "Current challenges in radiation therapy" (Dr. Thorsten Frenzel, University of Hamburg Medical Center - UKE) - Chair person: Dr. Theresa Staufer

Current challenges in radiation therapy (Dr. Frenzel, Radiation therapy)

v20250218_Frenzel_Handout.pdf

11:40 → 12:15 Keynote 5 - Infectious Diseases: "Mathematical modeling of COVID-19 spread from physics view point" (Prof. Yoichi Ikeda, Osaka University) - Chair: Dr. Theresa Staufer

Mathematical modeling of COVID-19 spread from physics view point (Prof. Yoichi Ikeda, Infectious desease)

12:15 → 12:50 Keynote 6 - Infectious Diseases: "Replication of SARS-CoV-2 in adipose tissue determines organ and systemic lipid metabolism in hamsters and humans" (Dr. Zoé Schmal, Leibniz-LIV) - Chair: Dr. Theresa Staufer

"Replication of SARS-CoV-2 in adipose tissue determines organ and systemic lipid metabolism in hamsters and humans" (Dr. Zoé Schmal, Leibniz-LIV)

12:50 → 13:45 Break

13:45 → 14:05 Student presentation O1 - "Luminescence behaviour of rhenium complexes changed by protonation/deprotonation of azole ligands", Sodai Miyamoto - Chair: Dr. Yoichi Ikeda

Both the Re-186 and 188 isotopes emit beta and gamma rays with energies suitable for cancer treatment and for diagnostic imaging. Therefore, rhenium complexes are expected to be used as radiopharmaceuticals for simultaneous treatment and diagnosis. In addition, the rhenium complexes with visible luminescence make it easier to visually monitor the tissues and cells in which the complexes accumulate. Since luminescence is affected by the surrounding environment, such as temperature, pH, and oxygen concentration, the luminescence measurement can provide information about the surroundings. In this study, a series of ligands, [2-(3-pyrazolyl)pyridine (H-N2py), 2-[1,2,3]-triazol-4-yl-pyridine (H-N3py), and 2 -(tetrazol-5-yl)-pyridine (H-N4py)] were used. The tricarbonyl Re(I) complexes [ReCl(CO)3(H-N2py)] (1-H), [ReCl(CO)3(H-N3py)] (2-H), [ReCl(CO)3(N4py)]- (3) were newly synthesized. The new complexes were characterized by elemental analysis, single crystal X-ray structure analysis, IR, UV-Vis, and 1H NMR spectroscopy. The complexes 1-H and 2-H are protonated, while 3 is deprotonated because H-N4py has a smaller pKa than H-N2py and H-N3py. The complexes 1-H and 2-H were deprotonated by 1,8-diazabicyclo[5.4.0]undec-7-one in DMSO to give [ReCl(CO)3(N2py)]- (1) and [ReCl(CO)3(N3py)]- (2). The complex 3 was not protonated by an addition of p-toluenesulfonic acid in DMSO. For 1-H, the emission maximum wavelength (em) at 557 nm in DMSO was not changed upon deprotonation, while the emission quantum yield (em) decreased from 5.0 × 10-3 to 7.0 × 10-4. The complex 2-H showed a 17 nm blue shift of the emission maximum from 553 nm to 536 nm upon deprotonation and the em decreased from 3.0 × 10-3 to 1.1 × 10-3. The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

14:05 → 14:25 Student presentation O2 - "Solid-liquid extraction studies of group 2 elements with DGA-resin towards the research of chemical properties of element 102, Nobelium", Enni Khult - Chair: Dr. Yoichi Ikeda

Element 102, Nobelium (No), is an actinide with unique chemical properties. No exhibits +2 oxidation state in aqueous solutions and similar behavior to that of group 2 elements. However, recent studies have shown that No may be a softer acid. Further research is needed to understand No’s chemical properties, which might be influenced by relativistic effects. For a systematic chemical study of No, extraction with DGA ligands is proposed. In this work, we investigated the behavior of group 2 elements in extraction from nitric acid using DGA-resin and performed relativistic DFT calculations of extracted M(II)-DGA complexes. The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

14:25 → 14:45 Student presentation O3 - "Abscopal Effect in Pancreatic Cancer: Combined Immune Checkpoint Inhibitor and Fractionated Carbon Ion Irradiation Therapy", Ayaka Okuuchi - Chair: Dr. Theresa Staufer

Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate and no effective treatment. Our previous study showed that the combination therapy of an immune checkpoint inhibitor, anti-CTLA-4 antibody (C4), and high-dose photon (16 Gy or 8 Gy x 3 fractions) and carbon-ion (C-ion) irradiation (8.2 Gy or 4.1 Gy x 3 fractions) shrank not only irradiated tumor but also unirradiated tumor, which is known as the abscopal effect. C-ion irradiation has some physical advantages, including Bragg-peak, enabling highly conformal dose to tumors and stronger cell killing effect than photon irradiation. Nevertheless, due to the proximity of risk organs such as stomach and duodenum around pancreas, dose reduction is preferred, provided that it can achieve comparative tumor control and abscopal effect. We therefore investigated whether combination therapy of C4 and medium-dose of C-ion irradiation induces the abscopal effect, along with changes in tumor microenvironment (TME). C-ion irradiation was conducted at the National Institutes for Quantum Science. C57BL/6 mice inoculated murine PDAC cells at both legs were irradiated to only one leg. The mice were assigned to the following groups: C4, 5.1 Gy+C4, and 2.1 Gy x 3 fractions+C4 groups. The doses of 5.1 Gy and 2.1 Gy x 3 fractions were found to be the biological equivalent dose to 10 Gy with photon irradiation based on our experimental data. All mice were administered with C4 intraperitoneally 3 times every 3 days. Half of mice in 5.1 Gy+C4 group experienced only local control, whereas half of those mice exhibited both local control and abscopal effect. Interestingly, six of seven mice in 2.1 Gy x 3 fractions+C4 group experienced both local control and abscopal effect, while one of seven mice experienced only local control. Compared to 5.1 Gy+C4 group, the proportion of cytotoxic T lymphocytes (CTL) was significantly increased in 2.1 Gy x 3 fractions+C4 group for both irradiated and unirradiated tumors, leading to the increased CTL/regulatory T cells (Treg) ratio at 5 days after the final treatment. These results suggest that not single but fractioned irradiation with C4 contributes to the induction of the abscopal effect and improvements of TME even at lower doses with C-ion than photon irradiation. We are currently developing an experimental system that replicates the unique microenvironment of PDAC, including stroma and cancer associated fibroblasts. This aspect will be further discussed in the presentation. The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

14:45 → 15:05 Student presentation O4 - "Effect of ultra-high dose rate particle irradiation on cell invasion in breast cancer cells", Karin Oniwa - Chair: Dr. Theresa Staufer

【Background and Aims】 Currently, normal tissue sparing and local tumor control at ultra-High Dose Rate (uHDR) irradiation have been reported with particles and photons. Our group is interested in the effect of radiation to metastatic potentials on irradiated cells. We focused on the comparison of cell invasive capabilities between uHDR and normal dose rate (NDR) irradiated cells with carbon ion beams and proton beams on breast cancer cell lines. 【Methods】 MDA-MB-231 (MM231: triple negative human breast cancer cells) and MCF-7 (estrogen receptor positive human breast cancer cells) were used. Cells were irradiated with 1.63, 4.36 and 5.65 Gy by carbon ion under uHDR (> 90 Gy/sec) or NDR (1.16 Gy/sec) at Osaka Heavy Ion Therapy Center (HIMAK), they were irradiated with proton (4.0, 12.0 and 15.0 Gy) under uHDR (250 Gy/sec) and NDR (1 Gy/sec) at Sumitomo Heavy Industries, Ltd. E-cadherin, a type of invasion suppressor protein, was measured by western blotting. Matrigel invasion assays were conducted using living cells after 24 hours of irradiation. 【Results】In the results with carbon ion irradiation, MCF-7 showed increased expression of E-cadherin with 4.36 and 5.65 Gy at 50 keV/µm under uHDR irradiation compared to NDR. When cells were irradiated with 1.6 Gy at 19 keV/µm under uHDR, cell invasion was inhibited by MCF-7 compared to NDR. The dose to 4.36 Gy at 50 keV/µm, cell invasion was suppressed by 83% (MM231) and 58% (MCF-7) with uHDR compared to NDR. This result suggested that Epithelial-mesenchymal transition (EMT) can be suppressed in uHDR irradiation. However, EMT-related invasion was not observed in MM231. In the results with proton irradiation, there were no significant changes to the cell invasive capabilities between uHDR and NDR in MCF-7. However, MM231 showed a trend toward increased cell invasion ability with uHDR compared to NDR in all conditions. 【Conclusions】 Cell types exhibited varying response to EMT, and E-cadherin expression was influenced by uHDR carbon ion irradiation. 【Acknowledgement】 The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

Wednesday 19 February

09:00 → 09:35 Keynote 7 - High Energy and Nuclear Physics: "COMET — An Experiment to Search for Muon-to-Electron Conversion at J-PARC" (Prof. Masaharu Aoki, Osaka University) - Chair: Prof. Tadafumi Kishimoto

COMET — An Experiment to Search for Muon-to-Electron Conversion at J-PARC (Prof. Aoki, High energy and nuclear physics)

09:35 → 10:10 Keynote 8 - High Energy and Nuclear Physics: "Opening-up the parameter space for Axion-Like-Particle Dark Matter" (Prof. Dr. Geraldine Servant, University of Hamburg/DESY) - Chair: Prof. Tadafumi Kishimoto

"Opening-up the parameter space for Axion-Like-Particle Dark Matter" (Prof. Dr. Geraldine Servant, UHH/DESY)

10:10 → 10:45 Keynote 9 - Computational High Energy Physics: "Lattice quantum chromodynamics and hadron physics" (Prof. Kenji Sasaki, Osaka University) - Chair: Prof. Tadafumi Kishimoto

Lattice quantum chromodynamics and hadron physics (Prof. Kenji Sasaki, Osaka University)

10:45 → 10:55 Break

10:55 → 11:30 Keynote 10 - Condensed Matter Physics: "Semiclassical and quantum magnetic effects" (Prof. Michael Potthoff, University of Hamburg) - Chair: Dr. Thore Posske

Semiclassical and quantum magnetic effects (Prof. Michael Potthoff, Condensed matter)

11:30 → 12:05 Keynote 11 - Condensed Matter Physics: "Physics of moiré materials" (Prof. Mikito Koshino, Osaka University) - Chair: Dr. Thore Posske

Physics of moiré materials (Prof. Koshino, mputational high energy physics)

12:05 → 12:40 Keynote 12 - Condensed Matter Physics: "Chiral nanomagnetism" (Dr. Elena Vedmedenko, University of Hamburg) - Chair: Dr. Thore Posske

Chiral nanomagnetism" (Dr. Elena Vedmedenko, University of Hamburg) - Condensed matter physics

12:40 → 13:35 Break

13:35 → 13:55 Student presentation O5 - "Electronic State Analysis of Solid Th Compound for Elucidating the Decay Mechanism of Th-229m", Ryotaro Masuda - Chair: Dr. Kenji Sasaki

The excitation energy of Th-229m is 8.4 eV, the lowest among all nuclides. The decay pathways of Th-229m are thought to compete among Internal Conversion (IC), γ ray transition, and Electron Bridge (EB) transition. Considering the excitation energy of 8.3 eV, IC may be prohibited depending on the chemical state. For example, the ionization energy of neutral Th is 6.3 eV, which is lower than the excitation energy. Therefore, the bonds the excitation energy is larger than the ionization energy, leading to deexcitation via IC. On the other hand, the ionization energy of Th+ is 12.1 eV, which is higher than the excitation energy. In this case, IC is prohibited, resulting in deexcitation via γ ray transition or EB transition. Both IC electrons and γ rays have been observed in the decay of Th-229m. However, the reported half-lives of the γ-ray emissions vary. The γ-ray emission half-life has been measured for four types of the samples. The one is Th-229m in the ion trap, for which a half-life of 1400 s was reported. The second to fourth is Th-229m implanted in MgF2, CaF2 or LiSrAlF6, for which half-life of 2210 s, 1740 s and 1287 s were reported. One of the reasons for this difference in half-life is thought to be the chemical environment of Th-229m. In the crystal (CaF2, MgF2), Th interacts with the constituent atoms of the crystal, whereas in the ion trap method, the half-life of isolated Th is measured. This interaction may affect the half-life of Th-229m. This study aims to stably hold Th2+, 3+-229m using the rare gas matrix isolation method and observe γ rays. Even if γ rays are observed using this method, the half-life may not be equivalent with those reported in the previous studies due to interactions between Th and the rare gas. Therefore, in this presentation, we analyze the chemical state of Th in rare gas solids and changes in the electronic state of Th due to interactions with rare gases through theoretical calculations. As a result, it was found that Th-229m maintains an ionic state in the rare gas solid, which is thought to deexcite via γ ray transition. However, due to interactions with the rare gas, slight influx of electrons from the rare gas to Th was observed, leading to the increase of the number of valence electrons compared to isolated Th. Furthermore, due to the presence of a small number of electrons in the LUMO, there is a possibility that the outer-shell electron could be emitted as an IC electron. In the presentation, we will provide comprehensive discussion on the change of half-life of various Th-229m samples using the calculation results for isolated Th-229m ions and Th-229m in CaF2 and MgF2.

13:55 → 14:15 Student presentation O6 - "Revisiting the model for radiative neutrino masses with dark matter in the U(1)B−L gauge theory", Guohao Ying - Chair: Dr. Kenji Sasaki

The radiative seesaw model with gauged U(1)B−L ×Z2 extension is a well-motivated scenario which gives consistent predictions of active neutrino masses and the abundance of dark matter. Majorana masses of right-handed neutrinos, the lightest of which can be identified as dark matter, are given by the spontaneous breaking of the U(1)B−L gauge symmetry. We revisit this model with the latest constraints from dark matter searches, neutrino oscillations, flavor experiments and collider experiments. We explore the feasible parameter space of this model, and find that there are still allowed regions under the latest experimental constraints. We present new viable benchmark scenarios for this model, i.e., the right-handed neutrino dark matter scenario and the scalar dark matter scenario. We also mention the testability of these benchmark scenarios at future experiments. ＊The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

14:15 → 14:35 Student presentation O7 - "Measuring the Forces Between Quarks: A Journey with Lattice QCD and Supercomputers ", Tianchen Zhang - Chair: Dr. Thore Posske

Summary: I first shortly introduce the basics of quark model and lattice QCD. Then I present the results of gauge dependence of $c\bar{c}$ potentials extracted from Nambu-Bethe-Salpeter (NBS) wave functions. The potentials are obtained using the NBS amplitude method. A systematic comparison is conducted between results obtained in the Coulomb and Landau gauges. The numerical calculations are performed using 2+1 flavor QCD gauge configurations with the charm quark treated in the quenched approximation. We find that the central potentials in both gauges show excellent agreement at short distances but exhibit discrepancies at large distances. We attribute these discrepancies to insufficient suppression of excited-state contamination in the Landau gauge, which affects the linear-rising behavior of the potential at large distance. The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

14:35 → 14:45 Break

14:45 → 15:05 Student presentation H2 - "An Attempt to Extend the Adiabatic Theorem", Sarah Damerow - Chair: Dr. Thore Posske

15:05 → 15:25 Student presentation O8 - "Development of "Muon Spin Imaging", Soshi Ishitani - Chair: Dr. Thore Posske

μSR is a spectroscopy using a spin-polarized muon beam. It is a method to observe the muon spin rotation, relaxation and resonance by using the detection of positrons emitted asymmetrically to the muon spin axis, and is widely used as one of the physical property methods to search for magnetic fields inside materials. However, the conventional μSR can only measure physical properties of the entire sample because it uses detectors without position sensitivity. 　Therefore, we have developed a new method called muon spin imaging using position-sensitive detectors. This method can determine the muon stop position in the sample by tracking the muon and positron trajectories, and enables μSR measurements in a small area of the sample. Then, by analyzing the μSR spectra for each sample position, 3D imaging of the sample with various μSR parameters becomes possible. 　In this study, 2D images of a sample of a known material combination were produced using a surface muon beam with uniform energy, and the position resolution of the images was evaluated. The experiment was performed at the TRIUMF in September 2024, using a drift chamber and a fiber tracker for muon and positron position measurements, respectively. As a result, the distribution of the Al + Al2O3 sample was reproduced. Translated with DeepL.com (free version)＊The author is grateful to F-REI (JPFR24040302) for the support of travel expenses.

15:25 → 15:35 Closing session - Chair: Dr. Thore Posske