138 citations · 437 across the 10 of their papers we have counts for
10 papers
Evidence for axion miniclusters with an increased central density
Benedikt Eggemeier, Ananthu Krishnan Anilkumar, Klaus Dolag
We identify axion miniclusters collapsing in the radiation-dominated era and follow them to redshift with N-body simulations. We find that the majority of the densest minicl…
Post-inflationary structure formation boosted by parametric self-resonance
Benedikt Eggemeier, Peter Hayman, Jens C. Niemeyer +1
The post-inflationary Universe can pass through a long epoch of effective matter-dominated expansion. This era may allow for both the parametric amplification of initial fluctuatio…
Multifield Ultralight Dark Matter
Mateja Gosenca, Andrew Eberhardt, Yourong Wang +4
Ultralight dark matter (ULDM) is usually taken to be a single scalar field. Here we explore the possibility that ULDM consists of light scalar fields with only gravitational in…
Axion minivoids and implications for direct detection
Benedikt Eggemeier, Ciaran A. J. O'Hare, Giovanni Pierobon +2
In the scenario in which QCD axion dark matter is produced after inflation, the Universe is populated by large inhomogeneities on very small scales. Eventually, these fluctuations…
Stochastic Gravitational Waves from Post-inflationary Structure Formation
Benedikt Eggemeier, Jens C. Niemeyer, Karsten Jedamzik +1
Following inflation, the Universe may pass through an early matter-dominated phase supported by the oscillating inflaton condensate. Initially small fluctuations in the condensate…
Structure of Axion Miniclusters
David Ellis, David J. E. Marsh, Benedikt Eggemeier +3
The Peak-Patch algorithm is used to identify the densest minicluster seeds in the initial axion density field simulated from string decay. The fate of these dense seeds is found by…
Gravitational Collapse in the Post-Inflationary Universe
Benedikt Eggemeier, Bodo Schwabe, Jens C. Niemeyer +1
The Universe may pass through an effectively matter-dominated epoch between inflation and Big Bang Nucleosynthesis during which gravitationally bound structures can form on subhori…
Formation of inflaton halos after inflation
Benedikt Eggemeier, Jens C. Niemeyer, Richard Easther
The early Universe may have passed through an extended period of matter-dominated expansion following inflation and prior to the onset of radiation domination. Sub-horizon density…
First Simulations of Axion Minicluster Halos
Benedikt Eggemeier, Javier Redondo, Klaus Dolag +2
We study the gravitational collapse of axion dark matter fluctuations in the post-inflationary scenario, so-called axion miniclusters, with N-body simulations. Largely confirming t…
Formation and mass growth of axion stars in axion miniclusters
Benedikt Eggemeier, Jens C. Niemeyer
We study the formation and the subsequent mass growth of axion stars inside axion miniclusters. Numerically solving the Schrödinger-Poisson equations with realistic initial conditi…