東京大学 原子核科学研究センター

Center for Nuclear Study, The University of Tokyo

Posts

2024

OEDO-SHARAQ研究成果のプレスリリース

OEDOとSHARAQを用いた放射性同位体79Seの核変換データの研究成果がPhysics Letters Bに出版され、 プレスリリースを行いました(「長寿命核廃棄物の減容および宇宙での元素の起源の解明へ」)。成果記事について英国の文学部の教授より詩が送られました

Posted on 23 Feb, 2024

Read more...

RIKEN RIBF + CNS Seminar by Prof. Yi-Hua Lam (Feb27)

Place: Nishina Hall, RIKEN Wako Campus

Date: Feb. 27 (Tue) 13:30 - 15:00

Speaker: Prof. Yi-Hua Lam (Institute of Modern Physics, Chinese Academy of Sciences)

Title: Sensitivity of the SAX J1808.4−3658 Photospheric Radius Expansion Bursts to Thermonuclear Reaction-Rate Variations

Abstract: More than half of the discovered Type-I X-ray bursters generate photospheric radius expansion (PRE) bursts. Nevertheless, the PRE bursting mechanism is not adequately understood due to the intricate thermo-hydrodynamics, varying accretion rates and non-constant recurrence times throughout a series of consecutive type-I X-ray bursts (XRBs). A set of PRE-burst models matching with observations are highly desired within the community to understand the burst mechanism and evolution of thermo-hydrodynamics, and to unfold the information embedded in X-ray signals, especially the properties of the accreting neutron star of a low-mass X-ray binary, nucleosynthesis, and burst ash composition. To construct these PRE models, identifying and reducing the uncertainties of important thermonuclear reactions are our prime aims. Here we investigate the sensitivity of PRE-burst models for the SAX J1808.4–3658 X-ray source on the uncertainties in (alpha, p), (alpha, gamma), (p, alpha), and (p, gamma) nuclear reaction rates. The fully self-consistent PRE-burst models consider the mutual influence between changes in extreme astrophysical conditions and changes in nuclear energy generation throughout the evolution of the sequential bursts. These PRE-burst models are instantiated from the state-of-the-art one-dimensional multi-zone thermo-hydrodynamic stellar evolution code, KEPLER. The impacts of all relevant reaction rates of proton-rich isotopes up to around mass 80 are individually studied by scaling up and down the respective reaction rate for a factor of 10. We identify and present a number of uncertain reaction rates that significantly influence the reproduction of observables (i.e., burst light curves, fluences, and recurrence times) and the prediction of burst ashes. The PRE-burst model is more sensitive to the change of reaction rates compared to all previous sensitivity studies. Moreover, this is the first XRB sensitivity study based on direct comparison with observations. In this talk, I will present the sensitivity-study results, deepening our understanding of the nuclear processes that shape observables of PRE bursts, and serving as a guidance for future nuclear astrophysics to reduce nuclear uncertainties in PRE models.

Posted on 16 Feb, 2024

Read more...

2023

特任研究員/教務補佐員(若干名)公募

東京大学原子核科学研究センター(CNS)では下記のリンクの通り、 特任研究員および教務補佐員を募集いたします。 ご関心をお持ちの方へご周知いただきますよう、よろしくお願い申し上げます。

東京大学大学院理学系研究科附属原子核科学研究センター センター長  酒見 泰寛

・特任研究員 https://www.s.u-tokyo.ac.jp/ja/recruit/?id=1565

・教務補佐員  https://www.s.u-tokyo.ac.jp/ja/recruit/?id=1567

 公募〆切は1月10日(水)です。

Posted on 18 Dec, 2023

Read more...

花井さんが筆頭著書のSR-PPACについての投稿論文が受理されました。

花井さんが筆頭著書のSR-PPACについての技術論文がPTEPに掲載が決定されました。

Posted on 14 Nov, 2023

Read more...

Chillery特任研究員が筆頭著書のOEDOでの実験についての論文が受理されました。

Thomas Chillery特任研究員が筆頭著者のOEDOでの論文がPTEPに受理されました。 長寿命核分裂片93Zrと重陽子との反応断面積についての論文です。

Posted on 13 Nov, 2023

Read more...

特任研究員公募

東京大学原子核科学研究センター(CNS)では下記のリンクの通り、 OEDOを用いた物理を推進する特任研究員を募集いたします。 ご関心をお持ちの方へご周知いただきますよう、よろしくお願い申し上げます。 東京大学大学院理学系研究科附属原子核科学研究センター センター長  酒見 泰寛

https://www.s.u-tokyo.ac.jp/ja/recruit/?id=1542

Posted on 15 Oct, 2023

Read more...

`特任研究員の公募`

東京大学原子核科学研究センター(CNS)では下記のリンクの通り、 インビームガンマ線核分光研究を推進する特任研究員を募集いたします。 ご関心をお持ちの方へご周知いただきますよう、よろしくお願い申し上げます。

東京大学大学院理学系研究科附属原子核科学研究センター センター長  酒見 泰寛

https://www.s.u-tokyo.ac.jp/ja/recruit/?id=1540 公募〆切は11月6日(月)です。

Posted on 15 Oct, 2023

Read more...

CNS + RNC RHIC Phys Res Lab Seminar by Dr. H. Otono (Sep15)

Place: Nishina Hall, RIKEN Wako Campus + hybrid

Date: Sep. 15 (Fri) 14:00 - 15:30

Speaker: Dr. Hidetoshi Otono (Kyushu Univ., Research Center for Advanced Particle Physics)

Title: First results from the FASER experiment at the LHC and prospect toward Forward Physics Facility in HL-LHC era Abstract:FASER, the ForwArd Search ExpeRiment, is an LHC experiment located 480 m downstream of the ATLAS interaction point along the beam collision axis. One of the major purposes of FASER is to detect and study TeV-energy neutrinos produced in the proton-proton collision at the LHC.

TeV-energy neutrinos will be sensitive to the very forward production of light hadrons and charmed mesons, providing access to both the very low-x and the very high-x regions of the colliding protons. The former regime is sensitive to novel QCD production mechanisms, such as BFKL effects and non-linear dynamics, as well as the gluon parton distribution function (PDF) down to x ∼ 10−7, well beyond the coverage of other experiments and providing key inputs for astroparticle physics. The latter regime provides information on open questions relating to the high-x PDFs, and in particular intrinsic charm. In addition, the FPF acts as a neutrino-induced deep-inelastic scattering (DIS) experiment with TeV-scale neutrino beams. The resulting measurements of neutrino DIS structure functions represent a valuable handle on the partonic structure of nucleons and nuclei, particularly their quark flavour separation, that is fully complementary to the charged-lepton DIS measurements expected at the upcoming Electron-Ion Collider (EIC).

FASER has been taking collision data since the start of LHC Run3 in July 2022. This talk will focus on giving an overview of the FASER detector and will also present our first physics results using a dataset collected in 2022, where we were the first to directly observe neutrino interactions at a particle collider experiment [1]. Toward the HL-LHC (High-Luminosity LHC) era from 2029, a new dedicated experimental cavern called Forward hysics Facility has been proposed, which is also discussed [2].

[1] https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.031801

[2] https://iopscience.iop.org/article/10.1088/1361-6471/ac865e

Posted on 10 Sep, 2023

Read more...

A3FCNSSS23

第21回の国際サマースクール A3F-CNSSS23が理化学研究所仁科ホール、および小柴ホールにて開催されます。

Posted on 31 Jul, 2023

Read more...

2020

CNS Summer School 2020

CNS Summer School 2020を開催いたします。

詳細はこちらから

過去のCNS Summer Schoolはこちらから

Posted on 21 Jul, 2020

Read more...