ESO VLT Optical Spectroscopy of BL Lac Objects IV
: Sbarufatti B, Treves A, Decarli R, Veronesi A, Kotilainen JK, Ciprini S, Falomo R, Romano P
: 2010
: Accretion and Ejection in AGN: a Global
: ACCRETION AND EJECTION IN AGN : A GLOBAL VIEW
: ASTR SOC P
: 427
: 213
: 214
: 2
: 978-1-58381-734-6
Among Active Galactic Nuclei BL Lacertae objects are characterized by the extreme weakness or complete absence of lines in their optical spectra. This hinders the measurement of their redshift, making it difficult to model and study the intrinsic properties of this class of objects. Here we report new results from an ongoing program of high S/N optical spectroscopy of BL Lacs performed with the ESO VLT under non-optimal sky conditions.