Scientific Report on Low Energy Absorption Features Detected by BeppoSAX LECS in Bright Blazar Targets

The apparency of low energy absorption features in Blazar LECS spectra has been reported during the early phase of the BeppoSAX mission (e.g. by Grandi et al. 1997 for 3C~273 SVP data; Giommi et al. 1997 for PKS 2155--304 SVP data), with data reduction and analysis tools released prior to July 1997. We set up a robust method to investigate the reliability of absorption features detections in LECS data of bright blazars. The analysis shows that similar features are common to all datasets (with possibly the exception of 3C~273 SVP data). This suggests that most of the features observed from 0.2 to 1 keV are possibly due to miscalibration of the instrument response. The reported problems have been overcome with the latest release of calibrations (September 1997).