4 papers
Cosmic strings and domain walls: the impact of CMB -mode data
Luca Caloni, Ricardo Z. Ferreira, Lara Sousa +1
We analyse CMB constraints on stable networks of cosmic strings and domain walls using for the first time full Planck 2018 data together with BICEP/Keck 2018 -mode measurements.…
ALP couplings to muons and electrons: a comprehensive analysis of supernova bounds
Ricardo Z. Ferreira, M. C. David Marsh, Eike Ravensburg
We provide a comprehensive analysis of the phenomenology of axion-like particles (ALPs) produced in core-collapse supernovae (ccSNe) through interactions with electrons and muons,…
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…
Axionic defects in the CMB: birefringence and gravitational waves
Ricardo Z. Ferreira, Silvia Gasparotto, Takashi Hiramatsu +2
The evidence for a non-vanishing isotropic cosmic birefringence in recent analyses of the CMB data provides a tantalizing hint for new physics. Domain wall (DW) networks have recen…