97 citations · 153 across the 6 of their papers we have counts for
8 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…
Collapsing Domain Wall Networks: Impact on Pulsar Timing Arrays and Primordial Black Holes
Ricardo Z. Ferreira, Alessio Notari, Oriol Pujolàs +1
Unstable domain wall (DW) networks in the early universe are cosmologically viable and can emit a large amount of gravitational waves (GW) before annihilating. As such, they provid…
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…
Strong supernovae bounds on ALPs from quantum loops
Ricardo Z. Ferreira, M. C. David Marsh, Eike Müller
We show that in theories of axionlike particles (ALPs) coupled to electrons at tree-level, the one-loop effective coupling to photons is process dependent: the effective coupling r…