Buscar
Mostrando ítems 51-60 de 944
The gamma-ray sky seen at X-ray energies. I. Searching for the connection between X-ray and gamma-rays in Fermi BL Lac objects
(EDP Sciences, 2019-10)
Context. BL Lac objects are an extreme type of active galactic nuclei (AGNs) that belong to the largest population of γ-ray sources: blazars. This class of AGNs shows a double-bumped spectral energy distribution that is ...
Luminous x-ray agn in clusters of galaxies
(The Astrophysical Journal Letters, 2010)
The γ -ray sky seen at X-ray energies: II. The swift hunt of fermi BL lac objects among unidentified γ -ray sources
(EDP Sciences, 2020-06)
Context. Nearly 50% of all sources detected by the Fermi Large Area Telescope are classified as blazars or blazar candidates, one of the most elusive classes of active galaxies. Additional blazars can also be hidden within ...
The clusters Abell 222 and Abell 223: a multi-wavelength view
(EDP SCIENCES S A, 2010)
Context. The Abell 222 and 223 clusters are located at an average redshift z similar to 0.21 and are separated by 0.26 deg. Signatures of mergers have been previously found in these clusters, both in X-rays and at optical ...