166 citations · 405 across the 14 of their papers we have counts for
14 papers
Eleven-year, 22-year and ~90-year solar cycles discovered in nitrate concentrations in a Dome Fuji (Antarctica) ice core
Yuko Motizuki, Yoichi Nakai, Kazuya Takahashi +2
Ice cores are known to yield information about astronomical phenomena as well as information about past climate. We report time series analyses of annually resolved nitrate variati…
Gravitational Wave Physics and Astronomy in the nascent era
Makoto Arimoto, Hideki Asada, Michael L. Cherry +50
The detections of gravitational waves (GW) by LIGO/Virgo collaborations provide various possibilities to physics and astronomy. We are quite sure that GW observations will develop…
Diverse Jet Structures Consistent with the Off-axis Afterglow of GRB 170817A
Kazuya Takahashi, Kunihito Ioka
The jet structure of short gamma-ray bursts (GRBs) has been controversial after the detection of GRB 170817A as the electromagnetic counterparts to the gravitational wave event GW1…
Inverse reconstruction of jet structure from off-axis gamma-ray burst afterglows
Kazuya Takahashi, Kunihito Ioka
The gravitational wave event GW170817 and the slowly-rising afterglows of short gamma-ray burst GRB 170817A clearly suggest that the GRB jet has an angular structure. However the a…
A Mechanism for Triple-Ridge Emission Structure of AGN Jets
Taiki Ogihara, Kazuya Takahashi, Kenji Toma
Recent radio VLBI observations of the relativistic jet in M87 radio galaxy have shown a triple-ridge structure that consists of the conventional limb-brightened feature and a centr…
Linear Analysis of the Shock Instability in Core-collapse Supernovae: Influences of Acoustic Power and Fluctuations of Neutrino Luminosity
Ken'ichi Sugiura, Kazuya Takahashi, Shoichi Yamada
This paper is a sequel to Takahashi et al. (2016), in which the authors investigated the influences of fluctuations in pre-shock accreting matter on the linear stability of the sta…
On the importance of progenitor asymmetry to shock revival in core-collapse supernovae
Hiroki Nagakura, Kazuya Takahashi, Yu Yamamoto
The progenitor stars of core-collapse supernovae (CCSNe) are asymmetrically fluctuating due to turbulent convections in the late stages of their lives. The progenitor asymmetry at…
Parabolic Jets from the Spinning Black Hole in M87
Masanori Nakamura, Keiichi Asada, Kazuhiro Hada +18
The M87 jet is extensively examined by utilizing general relativistic magnetohydrodynamic (GRMHD) simulations as well as the steady axisymmetric force-free electrodynamic (FFE) sol…
Fast-spinning black holes inferred from symmetrically limb-brightened radio jets
Kazuya Takahashi, Kenji Toma, Motoki Kino +2
This paper theoretically investigates the relations between the structure of relativistic jets and produced synchrotron images, by using a steady axisymmetric force-free jet model.…
Links between the shock instability in core-collapse supernovae and asymmetric accretions of envelopes
Kazuya Takahashi, Wakana Iwakami, Yu Yamamoto +1
The explosion mechanism of core-collapse supernovae has not been fully understood yet but multi-dimensional fluid instabilities such as standing accretion shock instability (SASI)…
Linear analysis on the growth of non-spherical perturbations in supersonic accretion flows
Kazuya Takahashi, Shoichi Yamada
We analyzed the growth of non-spherical perturbations in supersonic accretion flows. We have in mind the application to the post-bounce phase of core-collapse supernovae (CCSNe). S…
Exact Riemann solver for ideal magnetohydrodynamics that can handle all types of intermediate shocks and switch-on/off waves
Kazuya Takahashi, Shoichi Yamada
We have built a code to obtain the exact solutions of Riemann problems in ideal magnetohydrodynamics (MHD) for an arbitrary initial condition. The code can handle not only regular…
Regular and non-regular solutions of the Riemann problem in ideal magnetohydrodynamics
Kazuya Takahashi, Shoichi Yamada
We have built a code to numerically solve the Riemann problem in ideal magnetohydrodynamics (MHD) for an arbitrary initial condition to investigate a variety of solutions more thor…
An Antarctic ice core recording both supernovae and solar cycles
Yuko Motizuki, Kazuya Takahashi, Kazuo Makishima +8
Ice cores are known to be rich in information regarding past climates, and the possibility that they record astronomical phenomena has also been discussed. Rood et al. were the fir…