VERITAS Blazar Observations - Recent Results

TL;DR

This paper reports recent VERITAS observations of multiple blazars, discovering new VHE gamma-ray emissions, analyzing their spectra, and modeling their broadband spectral energy distributions to understand their emission mechanisms.

Contribution

It provides new VHE gamma-ray detections from several blazars and presents multiwavelength data and spectral modeling, advancing understanding of blazar emission processes.

Findings

Detection of VHE gamma-ray emission from 1ES 0806+524 and W Comae.

Observation of a strong outburst from W Comae in March 2008.

Spectral energy distribution modeling of 1ES 2344+514.

Abstract

We present the discovery of very high energy (VHE) gamma-ray emission from the high-frequency-peaked BL Lac object 1ES 0806+524 (z=0.138) and the intermediate-frequency-peaked BL Lac object W Comae (z=0.102) with VERITAS. VHE emission was discovered from these objects during the 2007/2008 observing campaign, with a strong outburst from W Comae detected in mid-March, lasting a few days. Quasi-simultaneous spectral energy distributions are presented, incorporating optical (AAVSO), and X-ray (Swift/RXTE) observations. We also present the energy spectrum of the distant BL Lac (z=0.182) 1ES 1218+304 which was detected by VERITAS during the 2006/2007 observing campaign. The energy spectrum is discussed in the context of different models of absorption from the diffuse extragalactic background radiation. We present multiwavelength observations of the blazar Markarian 421 (z=0.03), including a strong flare initially detected by the Whipple 10m gamma-ray telescope. Finally we present a broadband spectral energy distribution for 1ES 2344+514 (z=0.044) which is successfully fit using a one zone synchrotron self-Compton model.