Episodic transient deformation revealed by the analysis of multiple GNSS networks in the Noto Peninsula, central Japan

流体とスロースリップに駆動された能登半島群発地震 --ソフトバンク独自基準点データを用いた地殻変動解析結果--. 京都大学プレスリリース. 2023-06-13.Since November 30, 2020, an intense seismic swarm and transient deformation have been continuously observed in the Noto Peninsula, central Japan, which is a non-volcanic/geothermal area far from major plate boundaries. We modeled transient deformation based on a combined analysis of multiple Global Navigation Satellite System (GNSS) observation networks, including one operated by a private sector company (SoftBank Corp.), relocated earthquake hypocenters, and tectonic settings. Our analysis showed a total displacement pattern over 2 years shows horizontal inflation and uplift of up to ~ 70 mm around the source of the earthquake swarm. In the first 3 months, the opening of the shallow-dipping tensile crack had an estimated volumetric increase of ~ 1.4 × 10⁷ m³ at a depth of ~ 16 km. Over the next 15 months, the observed deformation was well reproduced by shear-tensile sources, which represent an aseismic reverse-type slip and the opening of a southeast-dipping fault zone at a depth of 14–16 km. We suggest that the upwelling fluid spread at a depth of ~ 16 km through an existing shallow-dipping permeable fault zone and then diffused into the fault zone, triggering a long-lasting sub-meter aseismic slip below the seismogenic depth. The aseismic slip further triggered intense earthquake swarms at the updip

Post-fission properties of uranium isotopes: a hybrid method with Langevin dynamics and the Hauser-Feshbach statistical model

Background: Precise understanding of nuclear fission is crucial for experimental and theoretical nuclear physics, astrophysics, and industrial applications; however, the complete physical mechanics is unresolved due to the complexities. Purpose: In this study, we present a new method to describe the dynamical-fission process and following prompt-neutron emission, where we combine the dynamical fission calculation based on the Langevin method and the Hauser-Feshbach statistical model. Methods: Two methods are connected smoothly within the universal charge distribution and the energy conservation, allowing us to calculate a sequence of fission dynamics and post-fission phase, including prompt neutron emission. Results: Using a certain set of model parameters, we successfully reproduce the experimental primary-fission yields, total kinetic energy, independent-fission yields, and prompt neutron emissions for the neutron induced fission of ${}^{236}$U, a compound nucleus of ${\rm n} + {}^{235}{\rm U}$. We elucidate the physical mechanism of the characteristic features observed in previous experiments, such as shell properties. Additionally, we apply our calculation to two very neutron-rich uranium isotopes, i.e., ${}^{250}$U and ${}^{255}$U, which are not experimentally confirmed but are important for r-process nucleosynthesis. Theoretical results indicate that ${}^{250}$U exhibits an asymmetric multiple-peak fission yield distribution, while the neutron-rich ${}^{255}$U has a single peak due to symmetric fission. Our method predicts post-neutron emission fragments, where ${}^{250}$U shows a stronger neutron emissivity than ${}^{255}$U. Conclusions: Our framework is highly reproducible in the experiments and shows that the number of emitted neutrons after fission differs significantly in neutron-rich uranium fission depending on distributions of fission variables.Comment: 12 pages, 11 figures, submitted to PRC, Comments are welcom

Glycopeptoid nanospheres: glycosylation-induced coacervation of poly(sarcosine)

Conjugation of maltopentaose to water-soluble homo-poly(sarcosine) induced self-association and formed nanospheres (−150 nm) in water although homo-poly(sarcosine) was water-soluble and did not form any aggregates. Fluorescent probe experiments showed that the spheres were non-ionic glycopeptoid coacervate-like particles with both hydrophobic and hydrophilic domains inside

Fast Multipole Method for Periodic Scattering Problems

Abstract This presentation discusses an FMM for isotropic and anisotropic periodic boundary value problems for Maxwell's equations in 3D. The periodic Green function and its derivatives, which are essential to the present method, are derived with Fourier analysis. We then apply the proposed method to scattering problems for two dimensional array of spheres and silicon woodpile structures, which are standard models in the field of photonic crystals. For the silicon woodpile structures, we compare the obtained energy transmittances with those in the previous studies. We observe good agreements

A study on the automated VTR motion analysis system by Two Dimensional DLT Method

The purpose of this study was to establish the automated VTR motion analysis system by Two Dimensional Direct Linear Transformation Method. Video digitizer equipped with video cassette recorder, personal computer were used for the VTR film analysis, where the coordinates were automatically transferred into the computer. The position data calculated by 2D-DLT method were very accurate. The mean deviations of computed coordinates from the actual coordinates were 0.012m in the horizontal direction (x), and 0.013m in the vertical direction (y)