256 citations · 2.5k across the 78 of their papers we have counts for
8 papers · 1 filter
On the energy source of ultra-stripped supernovae
Ryo Sawada, Kazumi Kashiyama, Yudai Suwa
Ultra-stripped supernovae (USSN) with a relatively low ejecta mass of (e.g., iPTF14gqr and SN2019dge) are considered to originate from ultra-stripped carbon-oxygen…
AT2018lqh: Black Hole Born from a Rotating Star?
Daichi Tsuna, Kazumi Kashiyama, Toshikazu Shigeyama
Recently an intriguing transient AT 2018lqh, with only a day-scale duration and a high luminosity of , has been discovered. While several possib…
Multi-wavelength emission from magnetically arrested disks around isolated black holes
Shigeo S. Kimura, Kazumi Kashiyama, Kenta Hotokezaka
We discuss the prospects for identifying nearest isolated black holes (IBHs) in our Galaxy. IBHs accreting gas from the interstellar medium (ISM) likely form magnetically arrested…
ALMA and NOEMA constraints on synchrotron nebular emission from embryonic superluminous supernova remnants and radio-gamma-ray connection
Kohta Murase, Conor M. B. Omand, Deanne L. Coppejans +8
Fast-rotating pulsars and magnetars have been suggested as the central engines of super-luminous supernovae (SLSNe) and fast radio bursts, and this scenario naturally predicts non-…
Multi-wavelength View of the Type IIn Zoo: Optical to X-ray Emission Model of Interaction-Powered Supernovae
Daichi Tsuna, Kazumi Kashiyama, Toshikazu Shigeyama
Transients powered by interaction with the circumstellar medium (CSM) are often observed in wavelengths other than optical, and multi-wavelength modelling can be important when inf…
Magnetically Arrested Disks in Quiescent Black-Hole Binaries: Formation Scenario, Observable Signatures, and Potential PeVatrons
Shigeo S. Kimura, Takahiro Sudoh, Kazumi Kashiyama +1
We propose magnetically arrested disks (MADs) in quiescent black-hole (BH) binaries as the origin of the multiwavelength emission, and argue that this class of sources can dominate…
Gravitational wave backgrounds from coalescing black hole binaries at cosmic dawn: an upper bound
Kohei Inayoshi, Kazumi Kashiyama, Eli Visbal +1
The successive discoveries of binary merger events by Advanced LIGO-Virgo have been revealing the statistical properties of binary black hole (BBH) populations. A stochastic gravit…
A necessary condition for supernova fallback invading newborn neutron-star magnetosphere
Yici Zhong, Kazumi Kashiyama, Toshikazu Shigeyama +1
We numerically investigate the dynamics of a supernova fallback accretion confronting with a relativistic wind from a newborn neutron star (NS). The time evolution of the accretion…