collaborators

5 papers

astro-ph.HE2026

Sagittarius A* near-infrared flares polarization as a probe of space-time I: Non-rotating exotic compact objects

Nicolas Aimar, João Luís Rosa, Hanna Liis Tamm +1

The center of our galaxy hosts Sagittarius~A*, a supermassive compact object of solar masses, usually associated with a black hole. Nevertheless, black holes…

gr-qc2025

Twinkle twinkle dark star: Oscillating profiles from dark matter scalar solitons

Nicolas Aimar, Caio F. B. Macedo, João Luís Rosa +1

Real scalar fields, e.g. the axion, cannot condensate into stationary solitonic configurations to form starlike structures, eventually either dispersing or collapsing. However, by…

gr-qc2025

Polarimetry imprints of exotic compact objects: relativistic fluid spheres and gravastars

Hanna Liis Tamm, Nicolas Aimar, João Luís Rosa

Recent observations of polarimetric parameters of active galactic nuclei motivate the study of polarization in the spacetime of exotic compact objects which can mimic the features…

gr-qc2025

Astrometric and polarimetric imprints of hot-spots orbiting parametrized black holes

João Luís Rosa, Nicolas Aimar, Diego Rubiera-Garcia

We analyze the observational features of hot-spots orbiting parametrized black hole (BH) spacetimes. We select a total of four BH spacetimes, two from the Johanssen-Psaltis (JP) pa…

gr-qc2025

Polarimetry imprints of exotic compact objects: solitonic boson stars

João Luís Rosa, Nicolas Aimar, Hanna Liis Tamm

In this work we analyze the polarization observational properties of solitonic boson stars orbited by spherical hot-spots emitting synchrotron radiation from a thermal distribution…