VERITAS long term monitoring of Gamma-Ray emission from the BL Lacertae object

TL;DR

This paper reports on a long-term monitoring study of the BL Lacertae object using VERITAS, analyzing gamma-ray emissions during both active and quiescent states to understand the source's emission mechanisms.

Contribution

It provides the first extensive long-term gamma-ray monitoring data of BL Lacertae during different activity states, aiding in disentangling emission components.

Findings

Detection of gamma-ray emission during multiple states

Insights into the variability of gamma-ray flux

Correlation with multiwavelength observations

Abstract

BL Lacertae is the prototype of the blazar subclass known as BL Lac type objects. BL Lacertae object itself is a low-frequency-peaked BL Lac(LBL). Very high energy (VHE) gamma ray emission from this source was discovered in 2005 by MAGIC observatory while the source was at a flaring state. Since then, VHE gamma rays from this source has been detected several times. However, all of those times the source was in a high activity state. Former studies suggest several non-thermal zones emitting in gamma-rays, then gamma-ray flare should be composed of a convolution. Observing the BL Lacertae object at quiescent states and active states is the key to disentangle these two components. VERITAS is monitoring the BL Lacertae object since 2011. The archival data set includes observations during flaring and quiescent states. This presentation reports on the preliminary results of the VERITAS observation between January 2013 - December 2015, and simultaneous multiwavelength observations.