6 papers
Light neutrinophilic WIMP in the model
Tatsuya Aonashi, Shigeki Matsumoto, Yu Watanabe +1
Sub-GeV dark matter is an appealing thermal target because it can still be produced via the standard freeze-out mechanism; at such low masses, achieving freeze-out naturally points…
Detecting Sterile Neutrino Dark Matter at MeV Gamma-Ray Observatories
Subaru Fujisawa, Tatsuya Hayashi, Shigeki Matsumoto +1
We explore the indirect detection of sterile neutrino dark matter within the gauged extension of the Standard Model, in which three right-handed neutrinos account for…
Indirect Detection of Dark Matter Around a Supermassive Black Hole with High Energy-Resolution Gamma-Ray Telescopes
Yu Watanabe, Alexander Kusenko, Shigeki Matsumoto
We explore whether the unprecedented energy resolution of upcoming gamma-ray telescopes can uncover relativistic effects in photon spectra resulting from dark matter (DM) annihilat…
Light WIMPs and MeV Gamma-ray Detection with COSI
Yu Watanabe, Shigeki Matsumoto, Christopher M. Karwin +6
Light weakly interacting massive particles (WIMPs), whose masses are in the sub-GeV scale, have been attracting more attention due to the negative results searching for traditional…
Enhancing Compton telescope imaging with maximum a posteriori estimation: a modified Richardson-Lucy algorithm for the Compton Spectrometer and Imager
Hiroki Yoneda, Thomas Siegert, Israel Martinez-Castellanos +23
We present a modified Richardson-Lucy (RL) algorithm tailored for image reconstruction in MeV gamma-ray observations, focusing on its application to the upcoming Compton Spectromet…
Mediator Decay through mixing with Degenerate Spectrum
Ayuki Kamada, Takumi Kuwahara, Shigeki Matsumoto +2
The decay of the mediator particle into standard model (SM) particles plays a significant role in exploring the dark sector scenario. We consider such a decay, taking the dark phot…