プレスリリース, Press release

2024年7月8日 | 新着情報

Dr Miyagi and Collaborators have made a press release from the Technical University of Darmstadt, Germany, on solving the problem on the nuclear magnetic moment. Details can be found in this page.

宮城さんと共同研究者等が、原子核の磁気モーメントの計算に成功し、ドイツ・ダルムシュタット工科大学からプレスリリースを行いました。詳細はこちら。

Seminar (セミナー)2024.6.28 Michal Repisky & Lukas Konecny (The Arctic University of Norway)

2024年6月24日 | 新着情報

The following two seminars will be held on June 28, 2024, at Meeting Room A in Center for Computational Sciences, University of Tsukuba, starting from 15:15 pm.

  • Speaker: Michal Repisky
    Affiliation: Comenius University in Bratislava, Slovakia & UiT The Arctic University of Norway, Tromsø, Norway
    Title: Relativistic Hamiltonians and DFT
    Abstract: Despite the success of non-relativistic quantum mechanics in describing molecular and material properties, there are many phenomena for whose correct description the special theory of relativity has to be considered. These phenomena are dubbed relativistic effects and are prominent when the systems of interest involve heavy elements or spin. In my presentation I will show how the Dirac equation is solved in quantum chemistry while introducing the four-component Dirac-Coulomb Hamiltonian and relativistic DFT methodology. Moreover, I will present modern two-component X2C Hamiltonian based on algebraic decoupling of the original Dirac Hamiltonian and show that it allows to reproduce reference four-component results at a fraction of their cost allowing us to abandon the still widespread notion of the infeasibility of fully relativistic approaches.
  • Speaker: Lukas Konecny
    Affiliation: UiT The Arctic University of Norway, Tromsø, Norway & Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
    Title: Relativistic spectroscopy in frequency and time domains
    Abstract: I will present the extension of relativistic electronic structure methods into the realm of dynamical molecular properties in the form of relativistic time-dependent density functional theory (TDDFT). I will present two approaches to relativistic TDDFT as implemented in our computer program ReSpect. First is the conventional linear response TDDFT and its applications for electron absorption and circular dichroism spectroscopies with focus on the core region where both scalar and spin-orbit relativistic effects are especially pronounced. Next is the real-time solution of the Dirac-Kohn-Sham equation that offers access to non-linear optical properties as well as modern attosecond spectroscopies.

新メンバー：YUさん New member: Yu

2024年6月17日 | 新着情報

A new postdoc researcher, Dr. Yu has joined our group.
ポスドク研究員のYuさんが研究室のメンバーに加わりました。

研究topics「仮想粒子を用いて原子核の実態に迫る！」（清水さん） Research topic: Using Virtual Particles to Get Closer to the Reality of the Atomic Nucleus! (Shimizu)

2024年5月29日 | 新着情報

研究topicsに清水さんの紹介記事が掲載されました。

研究者に聞く「仮想粒子を用いて原子核の実態に迫る！」

An article introducing Prof. Shimizu’s research is published in Research topic in CCS website (in Japanese).

仮想粒子を用いて原子核の実態に迫る！

ハイライト論文に選定 A paper selected as Editors’ Suggestion

2024年5月2日 | 新着情報

A paper by N. Hinohara and collaborators has been published in Physical Review C of American Physical Society, and selected as an Editors’ Suggestion. The paper proposes a new computational method for the quasiparticle-phonon coupling.

有限振幅法の新たな拡張による準粒子・振動結合の計算手法を提案した論文（著者：日野原・その他）が、アメリカ物理学会のPhysical Review Cに出版され、Editors’ Suggestionに選ばれました。

佐藤さん准教授に昇任　Dr Sato promoted to Associate Professor

2024年5月1日 | 新着情報

助教だった佐藤駿丞さんが准教授になりました。おめでとうございます。

Assistant Professor Shunsuke A. Sato has been promoted to Associate Professor. Congratulations!

新メンバー：宮城さん、YUさん、庄司さん、萩原さん、赤井さん、千葉さん New members: Yu, Shoji, Hagihara, Akai, and Chiba

2024年4月5日 | 新着情報

A new assistant professor, Dr Miyagi, postdoc researcher, Dr Yu, and two graduate students in the Master course, Shoji and Hagihara, have joined our group. In addition, two undergraduate fourth-year students, Akai and Chiba, will perform the graduation research in our group.
助教の宮城さん、ポスドク研究員のYuさん、大学院生（M1）の庄司さん、萩原さん、４年生・卒研生の赤井さん、千葉さんが研究室のメンバーに加わりました。

Ruike-san got Gamma24 Jury Prize 類家さん国際研究会Gamma24ポスター発表審査員賞受賞

2024年3月28日 | 新着情報

Ms. Ruike has received the Jury Prize for the poster presentation at the workshop on frontier nuclear studies with gamma-ray spectrometer arrays (gamma24).

類家さんが国際研究会gamma24にてポスター発表の審査員賞を受賞しました。

Seminar (セミナー)2024.1.9 Moemi Matsumoto (Tohoku University)

2024年1月5日 | 新着情報

The following seminar will be given by Ms. Moemi Matsumoto in Tohoku University on Tuesday, January 9th, 2024.

Lecturer: Moemi Matsumoto (Tohoku University)
Place: Meeting Room A, Center for Computational Sciences
Date/Time:: January 9, Tuesday, 13:45 pm –
Title:: Generator coordinate method with basis optimization
Abstract:: The generator coordinate method (GCM) has been a well-known method to describe nuclear collective motions. In GCM, one a priori specifies collective degrees of freedom (collective coordinates), such as nuclear deformations, and superposes many Slater determinants (SDs) within the selected collective subspace. However, there always exists arbitrariness in this approach in the choice of collective coordinates, for which one has to rely on empirical and phenomenological theory. With such a choice, it is not trivial whether the collective motion of interest can be optimally described. Therefore, a description of the collective motion without pre-set collective coordinates is desirable in order not to miss important degrees of freedom.
Recently, we extended GCM by optimizing both the basis SDs and the weight functions according to the variational principle [1]. With such simultaneous optimization of the basis states, one does not have to specify beforehand the relevant collective degrees of freedom covered by the set of basis SDs. In this seminar, I will present results of this new approach for sd-shell nuclei. Using the Skyrme functional, I will show that the optimized bases correspond to excited states along a collective path, unlike the conventional GCM which superposes only the local ground states. I will also discuss the interaction dependence of the numerical results.
[1] M. Matsumoto, Y. Tanimura and K. Hagino, Phys. Rev. C 108, L051302 (2023).
Language: English

Seminar (セミナー)2024.1.30 Cenxi Yuan (Sun Yat-sen University)

2023年12月25日 | 新着情報

The following seminar by Dr Cenxi Yuan (Sun Yat-sen University, China) will take place as follows:

Lecturer: Cenxi Yuan (Sun Yat-sen University in China)
Place: Meeting Room A, Center for Computational Sciences
Date/Time: January 30, 2024, Tuesday, 13:45 pm –
Title: Configuration-Interaction Shell Model (CISM) Understanding of Exotic Nuclei
Abstract: A solid grasp of nuclear forces and models is indispensable to understanding the quantum many-body systems, such as atomic nuclei. There is a wealth of data about exotic nuclei far from the stability line, encompassing information regarding energy levels, electromagnetic characteristics, and α and β decays. Describing these properties within a unified model and under a unified nuclear force is valuable.
In this presentation, I will introduce the Configuration-Interaction Shell Model (CISM) and its applications in exotic nuclei, from light to heavy ones. New nuclides, such as 214U, 207Th, and 18Mg, and their implications for nuclear structure will be discussed. Additionally, I will delve into the analysis of isomeric states within Ag and In isotopes and N = 127 isotones, utilizing nuclear interactions and focusing on Type I and II shell evolution. The talk will also introduce cross-shell excitations and isospin symmetry in light nuclei, highlighting the strongest isospin mixing observed in β decays. Lastly, preliminary findings will be presented regarding the uncertainty associated with CISM when employing a unified nuclear force with varying strengths in proton-proton and neutron-neutron interactions.
Language :English