5 papers
Optical spectroscopy of high redshift BL Lac objects
Renato Falomo, Aldo Treves, Simona Paiano +1
BL Lac objects (BLL) are defined by the presence of very weak (typically 5 Ã ) or even absent spectral lines. This makes determining their distance particularly challenging, es…
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…
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…
The Spectra of IceCube Neutrino (SIN) candidate sources -- V. Modeling and interpretation of multiwavelength and neutrino data
Xavier Rodrigues, Martina Karl, Paolo Padovani +5
A correlation has been reported between the arrival directions of high-energy IceCube events and gamma-ray blazars classified as intermediate- and high-synchrotron-peaked BL Lacs.…
Changing Look of the optical spectrum of the MeV Blazar PKS 0446+112 (4FGL J0449.1+1121)
Simona Paiano, Renato Falomo, Aldo Treves +2
Following the high activity of the gamma-ray Fermi source 4FGL J0449.1+1121 (PKS 0446+112), possibly associated with a IceCube neutrino event IC-240105A, we obtained optical spectr…