activity
20152021
most citedA common surface-density scale for the Milky Way and Andromeda dwarf satellites as a constraint on dark matter models

14 citations · 28 across the 7 of their papers we have counts for

collaborators

19 papers

astro-ph.HE2021

An Arecibo 327 MHz Search for Radio Pulsars and Bursts in the Dwarf Irregular Galaxies Leo A and T

Fronefield Crawford, Kohei Hayashi

We have conducted an Arecibo 327 MHz search of two dwarf irregular galaxies in the Local Group, Leo A and T, for radio pulsars and single pulses from fast radio bursts and other gi…

math.PR2021

A one-phase Stefan problem with non-linear diffusion from highly competing two-species particle systems

Kohei Hayashi

We consider an interacting particle system with two species under strong competition dynamics between the two species. Then, through the hydrodynamic limit procedure for the micros…

astro-ph.CO2021

Narrowing the mass range of Fuzzy Dark Matter with Ultra-faint Dwarfs

Kohei Hayashi, Elisa G. M. Ferreira, Hei Yin Jowett Chan

Fuzzy dark matter (FDM) is an attractive dark matter candidate motivated by small scale problems in astrophysics and with a rich phenomenology on those scales. We scrutinize the FD…

astro-ph.CO2020

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…

astro-ph.GA2020

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…

astro-ph.CO2020

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…