Discovery of Very High Energy γ-Ray Emission from the Low-Frequency-peaked BL Lacertae Object BL Lacertae

Abstract

The MAGIC collaboration observed BL Lacertae for 22.2 hr during 2005 August to December and for 26 hr during 2006 July to September. The source is the historical prototype and eponym of a class of low-frequency-peaked BL Lacertae (LBL) objects. A very high energy (VHE) g-ray signal was discovered with a 5.1 j excess in the 2005 data. Above 200 GeV, an integral flux of was measured, corresponding to approximately 3% 11 2 1