108 citations · 202 across the 11 of their papers we have counts for
11 papers
Lifetime of the singly charged Th nuclear isomer
Y. Shigekawa, A. Yamaguchi, K. Tokoi +6
The nucleus of thorium-229 (Th) has an exceptionally low-energy isomeric state (Th). Because its excitation energy is close to the energy levels of valenc…
Demonstration of inkjet-printed targets for activation cross-section measurements: deuteron-induced reactions on strontium up to 24 MeV
Akihiro Nambu, Masayuki Aikawa, Yudai Shigekawa +4
Excitation functions for the Sr() reactions producing Y, Y, and Y were measured up to 24-MeV deuteron energy using the stacked-foil techniqu…
Chemical effects on nuclear decay of U isomer in the uranyl form
Y. Shigekawa, K. Sawamura, S. Hashiba +8
The nucleus of uranium-235 (U) possesses an exceptionally low-energy isomeric state, U. Unlike most radioactive nuclides, whose nuclear-decay half-lives are consta…
X-ray-induced quenching of the Th clock isomer in CaF
Ming Guan, Michael Bartokos, Kjeld Beeks +27
Thorium-229 has the lowest nuclear-excited state (an isomer state) at approximately 8.356 eV, making it excitable with tabletop vacuum-ultraviolet lasers. Despite the recent succes…
Controlling Th isomeric state population in a VUV transparent crystal
Takahiro Hiraki, Koichi Okai, Michael Bartokos +27
The radioisotope Th-229 is renowned for its extraordinarily low-energy, long-lived nuclear first-excited state. This isomeric state can be excited by VUV lasers and the transition…
Production and chemical separation of Pa toward observation of rays of Th
Yudai Shigekawa, Xiaojie Yin, Akihiro Nambu +2
To observe the rays emitted from the low-lying isomeric state of Th (Th), we aim to dope fluoride crystals with its precursor Pa. In this study, w…
Estimation of radiative half-life of Th by half-life measurement of other nuclear excited states in Th
Y. Shigekawa, A. Yamaguchi, K. Suzuki +8
We perform coincidence measurements between particles and rays from a U source to determine the half-lives of the excited state in a Th nucleus. We first pr…
Absolute X-ray energy measurement using a high-accuracy angle encoder
Takahiko Masuda, Tsukasa Watanabe, Kjeld Beeks +16
This paper presents an absolute X-ray photon energy measurement method that uses a Bond diffractometer. The proposed system enables the prompt and rapid in-situ measurement of phot…
X-ray pumping of the Th-229 nuclear clock isomer
Takahiko Masuda, Akihiro Yoshimi, Akira Fujieda +27
Thorium-229 is a unique case in nuclear physics: it presents a metastable first excited state Th-229m, just a few electronvolts above the nuclear ground state. This so-called isome…
Towards an energy measurement of the internal conversion electron in the de-excitation of the Th-229 isomer
Simon Stellmer, Yudai Shigekawa, Veronika Rosecker +5
The first excited isomeric state of Th-229 has an exceptionally low energy of only a few eV and could form the gateway to high-precision laser spectroscopy of nuclei. The excitatio…
Nuclear resonant scattering experiment with fast time response: new scheme for observation of Th radiative decay
A. Yoshimi, H. Hara, T. Hiraki +24
Nuclear resonant excitation of the 29.19-keV level in Th with high-brilliance synchrotron- radiation and detection of its decay signal, are proposed with the aim of populat…