We present the analysis of archival data from ROSAT and ASCA of a serendipitous source PKS 2316-423. According to its featureless non-thermal radio/optical continuum, the object has been assumed as a BL Lac candidate in the literature. It was evident variable over the multiple X-ray observations. Specially, a variable high-energy tail of the synchrotron radiation is revealed. X-ray spectral analysis provided further evidence of its synchrotron-nature broad-band spectrum with steep and down-curved shape in the range of 0.1-10 keV. Further SED analysis suggest that it is a very low luminosity ``intermediate or high energy peaked BL Lac object. Given the unusual low luminosity, the further studies of PKS 2316-423 might give clues on the evolution properties of BL Lacs.
Download