Discovery and identification of two gamma-ray blazars at low galactic latitude with VERITAS

TL;DR

This paper reports the discovery of two low galactic latitude gamma-ray blazars using VERITAS, including their identification as BL Lac objects and the determination of their redshift for one source.

Contribution

It presents the first detection and identification of two gamma-ray blazars at low galactic latitudes with detailed optical follow-up.

Findings

Both sources are confirmed as BL Lac-type blazars.

Redshift of RX J0648.7+1516 is measured as z=0.179.

Gamma-ray emission characteristics are characterized.

Abstract

We report on the discovery of two gamma-ray sources at E > 200 GeV with VERITAS: RX J0648.7+1516 and VER J0521+211. Both sources are located at low galactic latitudes (|b| < 10 deg), and were previously classified as active galactic nuclei of unknown type. The discovery and characterization of gamma-ray emission together with follow-up optical spectroscopy permitted the identification of RX J0648.7+1516 and VER J0521+211 as BL Lac-type blazars. In the case of RX J0648.7+1516, a spectroscopic redshift of z = 0.179 was derived.