7 citations · 10 across the 17 of their papers we have counts for
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Higher-Order Analytical Expansion of Thawing Dark Energy with an Exponential Potential
Naoto Maki, Kazunori Kohri
Motivated by recent DESI results suggesting dynamical dark energy, we investigate the thawing scenario in quintessence with an exponential potential, …
X-ray signals converted from high-frequency gravitational waves emitted by spinning light primordial black hole dark matter
Asuka Ito, Kazunori Kohri
We investigate the detectability of high-frequency gravitational waves from the superradiance of light primordial black hole dark matter through photons converted in the Galactic m…
A cross-calibration approach for polarisation-sensitive detectors in CMB experiments: application to LiteBIRD's polarisation angle calibration
A. Novelli, F. Piacentini, S. Micheli +102
We present a cross-calibration algorithm that determines the relative calibration of detectors within the same frequency band of a CMB experiment. The method iteratively compares s…
Gravitational wave emission from nonspherical collapse in an early matter-dominated era using N-body simulations
Albert Escrivà, Tomohiro Harada, Kazunori Kohri +2
We study the dynamics of the collapse of a nonspherical overdense patch during an early matter-dominated era and the associated production of gravitational waves (GWs) using a semi…
Blue-tilted spectral running and the JWST early galaxy tension
Mikage U. Kobayashi, Gen Chiaki, Kazutaka Kimura +4
Recently, the James Webb Space Telescope (JWST) collaboration has found the unexpectedly large abundance of massive galaxies with stellar masses of at high…
Exponential Quintessence: Analytic Relationship Between the Current Equation of State Parameter and the Potential Parameter
Naoto Maki, Kazunori Kohri
Motivated by the indications of time-varying dark energy equation of state reported from DESI, we investigate a quintessence model with an exponential potential $V_0 e^{-λϕ/m_{\mat…
Exponential Quintessence Model: Analytical Quantification of the Fine-Tuning Problem in Dark Energy
Naoto Maki, Kazunori Kohri
In this paper, we investigate a quintessence field with an exponential potential motivated by the suggestion of time-varying dark energy from the DESI galaxy survey. Assuming a kin…
NANOGrav 15-year gravitational-wave signals from binary supermassive black-holes seeded by primordial black holes, and implications for the origins of Little Red Dots
Mikage U. Kobayashi, Kazunori Kohri
In this paper, we explain the recently reported a nHz-band gravitational-wave background from NANOGrav 15-year through the merger of binary super-massive black holes with masses of…
Isotropy, anisotropies and non-Gaussianity in the scalar-induced gravitational-wave background: diagrammatic approach for primordial non-Gaussianity up to arbitrary order
Jun-Peng Li, Sai Wang, Zhi-Chao Zhao +1
Produced nonlinearly by the enhanced linear cosmological curvature perturbations, the scalar-induced gravitational waves (SIGWs) can serve as a potentially powerful probe of primor…
Study of primordial non-Gaussianity and with the cross-correlations between the scalar-induced gravitational waves and the cosmic microwave background
Zhi-Chao Zhao, Sai Wang, Jun-Peng Li +1
The stochastic gravitational-wave background originating from cosmic sources contains vital information about the early universe. In this work, we comprehensively study the cross-c…