323 citations · 1k across the 43 of their papers we have counts for
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Classifying extended Higgs models through the trilinear Higgs boson coupling measurement at future colliders
Nagisa Hiroshima, Mitsuru Kakizaki, Shuhei Ohzawa
We investigate the trilinear Higgs boson coupling derived from the functional forms of various extended Higgs potentials. In light of experimental constraints on Higgs boson coupli…
Revisiting the limits on dark matter annihilation cross-section and decay lifetime in light of electron and positron fluxes
Nagisa Hiroshima, Kazunori Kohri, Partha Kumar Paul +1
We revisit the upper bound on the annihilation cross-section, of a stable dark matter (DM) of mass GeV by considering five different channels: $W^+…
An Analytic Prescription for -channel Singularities
Kento Asai, Nagisa Hiroshima, Joe Sato +2
The -channel singularity is a divergence in the scattering amplitude which occurs when a stable particle propagating in -channel scattering process becomes an on-shell state.…
Explosive production of Higgs particles and implications for heavy dark matter
Seishi Enomoto, Nagisa Hiroshima, Kohta Murase +1
It is widely believed that the parameter space for Higgs-portal dark matter that achieves the relic abundance through thermal freeze-out has already been tightly constrained, typic…
Dark Matter Line Searches with the Cherenkov Telescope Array
S. Abe, J. Abhir, A. Abhishek +562
Monochromatic gamma-ray signals constitute a potential smoking gun signature for annihilating or decaying dark matter particles that could relatively easily be distinguished from a…
MeV-scale reheating temperature and cosmological production of light sterile neutrinos
Takuya Hasegawa, Nagisa Hiroshima, Kazunori Kohri +3
We investigate how sterile neutrinos with a range of masses influence cosmology in MeV-scale reheating temperature scenarios. By computing the production of sterile neutrinos throu…