104 citations · 1.1k across the 42 of their papers we have counts for
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Probing Dark Matter Self-interaction with Ultra-faint Dwarf Galaxies
Kohei Hayashi, Masahiro Ibe, Shin Kobayashi +2
Self-interacting dark matter (SIDM) has gathered growing attention as a solution to the small scale problems of the collisionless cold dark matter (DM). We investigate the SIDM usi…
Diversity of dark matter density profiles in the Galactic dwarf spheroidal satellites
Kohei Hayashi, Masashi Chiba, Tomoaki Ishiyama
The core-cusp problem is one of the controversial issues in the standard paradigm of cold dark matter (CDM) theory. However, under the assumption of conventional spherical s…
Constraining Primordial Black Holes with Dwarf Galaxy Heating
Philip Lu, Volodymyr Takhistov, Graciela B. Gelmini +3
Black holes formed in the early universe, prior to the formation of stars, can exist as dark matter and also contribute to the black hole merger events observed in gravitational wa…
Formation of massive globular clusters with dark matter and its implication on dark matter annihilation
Henriette Wirth, Kenji Bekki, Kohei Hayashi
Recent observational studies of -ray emission from massive globular clusters (GCs) have revealed possible evidence of dark matter (DM) annihilation within GCs. It is, however, s…
Investigation of the Status of Unit 2 Nuclear Reactor of the Fukushima Daiichi by the Cosmic Muon Radiography
Hirofumi Fujii, Kazuhiko Hara, Shugo Hashimoto +19
We have investigated the status of the nuclear debris in the Unit-2 Nuclear Reactor of the Fukushima Daiichi Nuclear Power plant by the method called Cosmic Muon Radiography. In th…
EMPRESS. III. Morphology, Stellar Population, and Dynamics of Extremely Metal Poor Galaxies (EMPGs): Are EMPGs Local Analogs of High- Young Galaxies?
Yuki Isobe, Masami Ouchi, Takashi Kojima +16
We present the morphology and stellar population of 27 extremely metal poor galaxies (EMPGs) at with metallicities of 0.01--0.1 Z. We conduct multi-component sur…
N-body self-consistent stars-halo modeling of the Fornax dwarf galaxy
Galina Shchelkanova, Kohei Hayashi, Sergei Blinnikov
We present nearly self-consistent stellar-halo models of the Fornax dwarf spheroidal galaxy associated with the Milky Way galaxy. Such galaxies are dominated by dark matter and hav…
Investigation of Unit-1 Nuclear Reactor of the Fukushima Daiichi by Cosmic Muon Radiography
Hirofumi Fujii, Kazuhiko Hara, Kohei Hayashi +11
We have investigated the status of the nuclear fuel assemblies in Unit-1 reactor of the Fukushima Daiichi Nuclear Power plant by the method called Cosmic Muon Radiography. In this…
-factor estimation of Draco, Sculptor and Ursa Minor dwarf spheroidal galaxies with the member/foreground mixture model
Shun-ichi Horigome, Kohei Hayashi, Masahiro Ibe +3
Dwarf spheroidal galaxies (dSphs) are promising targets of indirect detection experiments searching for dark matter (DM) at present universe. Toward robust prediction for the amoun…
Spatial-segregation limit for exclusion processes with two components under unbalanced reaction
Kohei Hayashi
We consider exclusion processes with two types of particles which compete strongly with each other. In particular, we focus on the case where one species does not diffuse at all an…