323 citations · 1k across the 43 of their papers we have counts for
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A lower bound on primordial power spectrum from halo substructure
Shin'ichiro Ando, Nagisa Hiroshima, Koji Ishiwata +1
We investigate how the primordial curvature perturbation of a certain wavelength scale affects the halo and subhalo structure. Primordial power spectrum considered in this paper fe…
Supermassive black holes from inflation constrained by dark matter substructure
Shin'ichiro Ando, Shyam Balaji, Malcolm Fairbairn +2
Recent James Webb Space Telescope observations of high-redshift massive galaxy candidates have initiated renewed interest in the important mystery around the formation and evolutio…
Constraining the primordial curvature perturbation using dark matter substructure
Shin'ichiro Ando, Nagisa Hiroshima, Koji Ishiwata
We investigate the primordial curvature perturbation by the observation of dark matter substructure. Assuming a bump in the spectrum of the curvature perturbation in the wavenumber…
Semi-analytical frameworks for subhalos from the smallest to the largest scale
Nagisa Hiroshima, Shin'ichiro Ando, Tomoaki Ishiyama
Substructures of dark matter halo, called subhalos, provide important clues to understand the nature of dark matter. We construct a useful model to describe the properties of subha…
Impacts of new small-scale N-body simulations on dark matter annihilations constrained from cosmological 21cm line observations
Nagisa Hiroshima, Kazunori Kohri, Toyokazu Sekiguchi +1
We revisit constraints on annihilating dark matter based on the global 21cm signature observed by EDGES. For this purpose, we used the numerical data of the latest N-body simulatio…
Structure Formation Models Weaken Limits on WIMP Dark Matter from Dwarf Spheroidal Galaxies
Shin'ichiro Ando, Alex Geringer-Sameth, Nagisa Hiroshima +3
Dwarf spheroidal galaxies that form in halo substructures provide stringent constraints on dark matter annihilation. Many ultrafaint dwarfs discovered with modern surveys contribut…