Hisano, Junji, Kawasaki, Masahiro, Kohri, Kazunori, Nakayama, Kazunori
The excess of cosmic-ray electron and positron fluxes measured by the PAMELA satellite and ATIC balloon experiments may be interpreted as the signals of the dark matter annihilation or decay. In this...
Cosmological scenario of stop NLSP with gravitino LSP and the cosmic lithium problem (2008)
Kohri, Kazunori, Santoso, Yudi
The discrepancy on Li^7 and Li^6 abundances between the observational data and the standard Big Bang Nucleosynthesis theory prediction has been a nagging problem in astrophysics and cosmology, given...
More hilltop inflation models. (2007)
Kohri, Kazunori, Lin, Chia-Min, Lyth, David H.
Using analytic expressions, we explore the parameter space for hilltop inflation models with a potential of the form V0 ± m22−ap. With the positive sign and p>2 this converts the original hybrid...
Long Lived Charged Massive Particles and Big Bang Nucleosynthesis (2006)
Kohri, Kazunori, Takayama, Fumihiro
We consider Big Bang Nucleosynthesis(BBN) with long lived charged massive particles. Before decaying, the long lived massive particles recombines with a light element to form a bound state like a...
Cosmological Constraints on Gravitino LSP Scenario with Sneutrino NLSP (2006)
Kanzaki, Toru, Kawasaki, Masahiro, Kohri, Kazunori, Moroi, Takeo
We study the scenario where a sneutrino is the next lightest supersymmetric particle (NLSP) and decays into a gravitino and standard model particles. The daughter particles such as neutrinos and...
TeV Gamma-Rays from Old Supernova Remnants (2006)
Yamazaki, Ryo, Kohri, Kazunori, Bamba, Aya, Yoshida, Tatsuo, Tsuribe, Toru, Takahara, Fumio
We study the emission from an old supernova remnant (SNR) with an age of around 10^5 yrs and that from a giant molecular cloud (GMC) encountered by the SNR. When the SNR age is around 10^5 yrs,...
Can neutrino-cooled accretion disk be an origin of gamma-ray bursts? (2002)
Kohri, Kazunori, Mineshige, Shin
It is often considered that a massive torus with solar mass or so surrounding a stellar-mass black hole may be a central engine of a gamma-ray burst. We study the properties of such massive accretion...