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Long XMM observation of the narrow-line Seyfert 1 galaxy IRAS 13224−3809: rapid variability, high spin and a soft lag
The narrow-line Seyfert 1 galaxy IRAS 13224−3809 has been observed with XMM-Newton for 500 ks. The source is rapidly variable on time-scales down to a few 100 s. The spectrum shows strong broad Fe −…
Equation of State and Duration to Radiation Domination after Inflation.
The upper bound on the postinflationary duration before radiation domination reduces the uncertainty in inflationary observables even when couplings to additional light fields are included (at least under the assumption of perturbative decay).
Classical decay rates of oscillons
Oscillons are extremely long-lived, spatially-localized field configurations in real-valued scalar field theories that slowly lose energy via radiation of scalar waves. Before their eventual demise,…
Self-gravitating vector dark matter
We derive the non-relativistic limit of a massive vector field. We show that the Cartesian spatial components of the vector behave as three identical, non-interacting scalar fields. We find classes…
Self-resonance after inflation: Oscillons, transients, and radiation domination
Homogeneous oscillations of the inflaton after inflation can be unstable to small spatial perturbations even without coupling to other fields. We show that for inflaton potentials…
The First Three Seconds: a Review of Possible Expansion Histories of the Early Universe
It is commonly assumed that the energy density of the Universe was dominated by radiation between reheating after inflation and the onset of matter domination 54,000 years later. While the abundance…
Lectures on Reheating after Inflation
- K. Lozanov
- 9 July 2019
This lecture note provides a generic introduction to reheating after inflation, covering theoretical, phenomenological and observational aspects of the process.
The charged inflaton and its gauge fields: preheating and initial conditions for reheating
We calculate particle production during inflation and in the early stages of reheating after inflation in models with a charged scalar field coupled to Abelian and non-Abelian gauge fields. A…
Gravitational perturbations from oscillons and transients after inflation
We study the scalar and tensor perturbations generated by the fragmentation of the inflaton condensate into oscillons or transients after inflation, using nonlinear classical lattice simulations.…
Schwinger effect by an SU(2) gauge field during inflation
A bstractNon-Abelian gauge fields may exist during inflation. We study the Schwinger effect by an SU(2) gauge field coupled to a charged scalar doublet in a (quasi) de Sitter background and the…