Relativistic jets of active galactic nuclei have been known to exist for 100 years. Blazars with
their jet pointing close to our line of sight are some of the most variable and extreme objects …

This article reviews the recent observational results regarding γ-ray emission from active
galaxies. The most numerous discrete extragalactic γ-ray sources are AGNs dominated by …

Detection of the IceCube-170922A neutrino coincident with the flaring blazar TXS 0506+
056, the first and only∼ 3σ high-energy neutrino source association to date, offers a …

ABSTRACT The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on
2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates in …

ABSTRACT The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides
near real-time coverage of the X-ray sky in the energy range 15–50 keV. The BAT observes …

Employing Fermi-LAT gamma-ray observations, several independent groups have found
excess extended gamma-ray emission at the Galactic Center (GC). Both annihilating dark …

The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area
Telescope (LAT) in two years of scientific operation is presented. The second LAT AGN …

Magnetic reconnection in relativistic collisionless plasmas can accelerate particles and
power high-energy emission in various astrophysical systems. Whereas most previous …

Almost 10 yr of γ-ray observations with the Fermi Large Area Telescope have revealed
extreme γ-ray outbursts from flat spectrum radio quasars (FSRQs), temporarily making these …

Fermi has provided the largest sample of γ-ray-selected blazars to date. In this work we use
a complete sample of flat spectrum radio quasars (FSRQs) detected during the first year of …