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20232026
most citedGravitational Waves from Metastable Cosmic Strings in Supersymmetric New Inflation Model

7 citations · 8 across the 8 of their papers we have counts for

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6 papers · 1 filter

astro-ph.CO2026

Reviving the Affleck-Dine Curvaton Scenario with Compensated Isocurvature Perturbations

Masahiro Kawasaki, Shunsuke Neda

We revisit the Affleck-Dine curvaton scenario in the framework of supersymmetry, taking Q-ball formation into account. In this scenario, a scalar field carrying baryon number, name…

astro-ph.CO2026

Merger rate of initially clustered primordial black holes for the two-body channel

Kentaro Kasai, Masahiro Kawasaki, Kai Murai +1

Primordial black holes (PBHs) may form an initially clustered population depending on their production mechanism. Motivated by binary black-hole merger events observed by gravitati…

astro-ph.CO2026

Microlensing events and primordial black holes in the axionlike curvaton model

Kentaro Kasai, Masahiro Kawasaki, Kai Murai +1

Recently, Subaru Hyper Suprime-Cam (HSC) observations found 12 candidates for microlensing events. These events can be explained by primordial black holes (PBHs) with masses of $10…

astro-ph.CO2024★ 1 cited

Supermassive black hole formation from Affleck-Dine mechanism with suppressed clustering on large scales

Kentaro Kasai, Masahiro Kawasaki, Kai Murai +1

We study a primordial black hole (PBH) formation model based on the framework of the inhomogeneous Affleck-Dine (AD) mechanism, which can explain the seeds of supermassive black ho…

astro-ph.CO2023

Primordial Origin of Supermassive Black Holes from Axion Bubbles

Kentaro Kasai, Masahiro Kawasaki, Naoya Kitajima +3

We study a modification of the primordial black hole (PBH) formation model from axion bubbles. We assume that the Peccei-Quinn scalar rolls down in the radial direction from a larg…

astro-ph.CO2023

Clustering of Primordial Black Holes from QCD Axion Bubbles

Kentaro Kasai, Masahiro Kawasaki, Naoya Kitajima +3

We study the clustering of primordial black holes (PBHs) and axion miniclusters produced in the model proposed to explain the LIGO/Virgo events or the seeds of the supermassive bla…