5 citations · 7 across the 10 of their papers we have counts for
14 papers
Stimulated capture of axion dark matter around primordial black holes
Nuno P. Branco, João G. Rosa
We study the stimulated capture of axion and axion-like particles around primordial black holes, mediated by quartic self-interactions. We identify the parametric regions where Bos…
Lukewarm inflation and the QCD axion
Paulo B. Ferraz, António Torres Manso, João G. Rosa
We show that a late period of warm inflation, at temperatures just above the QCD scale, can dilute the abundance of the QCD axion produced by the misalignment mechanism, thus avoid…
Lukewarm inflation, primordial black holes and gravitational waves
Paulo B. Ferraz, António Torres Manso, João G. Rosa
We show that a secondary period of warm inflation, at temperatures parametrically below the GUT scale, may not only dilute any unwanted thermal relics formed after reheating but al…
Hawking emission of massive vector fields by Kerr black holes
Marco Calzà, Miguel Faria, Yuber F. Perez-Gonzalez +1
We compute, for the first time, the Hawking emission spectrum of massive vector (Proca) fields by spinning Kerr black holes, determining the associated greybody factors and the res…
String Axiverse Enhancement of Superradiant Dark Matter Production
Diogo S. Gorgulho, Jacob A. Litterer, João G. Rosa
We study the effects of string axion emission on dark matter production by light primordial black holes (PBHs), through both evaporation and superradiance. We show, in particular,…
From scalar clouds around evaporating black holes to boson star
Daniel Neves, João G. Rosa
We study, for the first time, the evolution of a scalar cloud bound to an evaporating black hole. Our simulations of the associated Schrödinger-Poisson system for non-relativistic…
Dark neutron stars from a heavy dark sector
Jacob A. Litterer, João G. Rosa
We study the formation and properties of dark neutron stars in a scenario where dark matter is made up of (heavy) dark baryons in a sequestered copy of the MSSM. This scenario natu…
Constraints on Dark Matter Structures around Gaia Black Holes
Nuno P. Branco, Ricardo Z. Ferreira, João G. Rosa +1
We demonstrate that Gaia's detection of stars on wide orbits around black holes opens a new observational window on dark matter structures -- such as scalar clouds and dark matter…
Preheated inflation
Diogo S. Gorgulho, João G. Rosa
We propose a new mechanism of non-thermal particle production during inflation based on a narrow parametric resonance, akin to the dynamics of post-inflationary preheating. The mec…
The inflation trilogy and primordial black holes
Paulo B. Ferraz, João G. Rosa
We propose an inflation scenario with three independent stages of cold, warm and thermal inflation, respectively, driven by different scalar fields, motivated by the large number o…
Superradiant Darwinism: survival of the lightest axion
Daniel Neves, João G. Rosa
We study the dynamical evolution of superradiant instabilities of rotating black holes for multiple axion fields with comparable masses, motivated by string theory constructions, w…
Evaporating Kerr black holes as probes of new physics
Marco Calzà, João G. Rosa
In the string axiverse scenario, primordial black holes (PBHs) can sustain non-negligible spin parameters as they evaporate. We show that tracking both the mass and spin evolution…
Determining the spin of light primordial black holes with Hawking radiation II: high spin regime
Marco Calzà, João G. Rosa
We propose a method to determine the mass and spin of primordial black holes based on measuring the energy and emission rate at the dipolar and quadrupolar peaks in the primary pho…
Thermal curvature perturbations in thermal inflation
Mar Bastero-Gil, Joaquim M. Gomes, João G. Rosa
We compute the power spectrum of super-horizon curvature perturbations generated during a late period of thermal inflation, taking into account fluctuation-dissipation effects resu…