4 papers
Sommerfeld enhancement from unstable final-state particles in dark matter annihilation
Tomohiro Abe, Ryosuke Sato, Takumu Yamanaka
We study the Sommerfeld enhancement of the annihilation cross section of dark matter into heavier unstable particles. In this process, the annihilation products become non-relativi…
New Source for QCD Axion Dark Matter Production: Curvature Induced
Cem Eröncel, Yann Gouttenoire, Ryosuke Sato +2
We discuss a novel mechanism for generating dark matter from a fast-rolling scalar field, relevant for both inflation and rotating axion models, and apply it specifically to the (Q…
A universal bound on the duration of a kination era
Cem Eröncel, Yann Gouttenoire, Ryosuke Sato +2
We show that primordial adiabatic curvature fluctuations generate an instability of the scalar field sourcing a kination era. We demonstrate that the generated higher Fourier modes…
Model implementations of axion dark matter from kinetic misalignment
Cem Eröncel, Ryosuke Sato, Géraldine Servant +1
The axion kinetic misalignment mechanism (KMM) opens the possibility of explaining dark matter for almost any axion mass and decay constant that are not accessible by the standard…