4 papers
Amnesia in the Axion Misalignment Landscape
Kierthika Chathirathas, Cem Eröncel, Mathieu Kaltschmidt +2
Pre-inflationary axion cosmologies admit a broad range of initial velocities and angles that generate a landscape of misalignment histories, whose nonlinear fate and small-scale st…
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…
ALP Dark Matter from Kinetic Fragmentation: Opening up the Parameter Window
Cem Eröncel, Ryosuke Sato, Geraldine Servant +1
The main mechanism responsible for Axion-Like-Particle (ALP) production in the early universe is the so-called misalignment mechanism. Three regimes have been investigated in this…