Highlights from TeV Extragalactic Sources

TL;DR

This paper reviews the significant progress in detecting extragalactic TeV sources, highlighting the increase from fewer than 20 to nearly 70 sources, mainly blazars, due to advancements in Cherenkov telescopes and multi-wavelength observations.

Contribution

It provides a comprehensive overview of recent discoveries in extragalactic TeV gamma-ray sources, emphasizing the detection of distant sources and technological advancements.

Findings

Number of TeV extragalactic sources increased from <20 to nearly 70 since 2007

Most sources are blazars up to redshift ~1

Recent detections include more distant sources at higher redshifts

Abstract

The number of discovered TeV sources populating the extragalactic sky in 2017 is nearly 70, mostly blazars located up to a redshift ~1. Ten years ago, in 2007, less than 20 TeV emitters were known, up to a maximum redshift of 0.2. This is a major achievement of current generation of Cherenkov telescopes operating in synergy with optical, X-ray, and GeV gamma-ray telescopes. A review of selected results from the extragalactic TeV sky is presented, with particular emphasis on recently detected distant sources.