3 papers
astro-ph.HE2025
Characterization of a sample of -ray active galactic nuclei
Alberto Ulgiati, Paolo Padovani, Paolo Giommi +2
We analyse 77 \textit{Fermi} sources and their potential low-energy counterparts previously proposed in the literature. These sources were classified as active galactic nuclei, mai…
astro-ph.HE2024
Search for the multiwavelength counterparts to extragalactic unassociated Fermi γ-ray sources
Alberto Ulgiati, Simona Paiano, Fabio Pintore +7
Aims. In this paper, we searched for multi-wavelength (X-ray, optical and radio) counterparts to the unassociated gamma-ray sources (UGS) of the Fermi 4FGL-DR4 catalog. The main go…
astro-ph.HE2024
Fast X-ray/IR observations of the black hole transient Swift~J1753.5--0127: from an IR lead to a very long jet lag
Alberto Ulgiati, Federico Maria Vincentelli, Piergiorgio Casella +16
We report on two epochs of simultaneous near-infrared (IR) and X-ray observations with a sub-second time resolution of the low mass X-ray binary black hole candidate Swift J1753.5-…