X-Ray Emission Properties of a Compact Symmetric Object Sample

We present a comprehensive analysis of the X-ray observations obtained from XMM-Newton and Chandra for a sample of bona-fide Compact Symmetric Objects (CSOs) to investigate their X-ray emission properties. Ultimately, we obtain 32 effective X-ray observational spectra from 17 CSOs. Most spectra can be well described by an absorbed single power-law model, with the exception of six spectra requiring an additional component in the soft X-ray band and two spectra exhibiting an iron emission line component. The data analysis results unveil the diverse characteristics of X-ray emission from CSOs. The sample covers X-ray luminosity ranging within 10(40)-10(45) erg s(-1), intrinsic absorbing column density (N-H(int)) ranging within 10(20)-10(23) cm(-2), and photon spectral index (Gamma(X)) ranging within 0.75-3.0. None of the CSOs in our sample have N-H(int) > 10(23) cm(-2), indicating that the X-ray emission in these CSOs is not highly obscured. The distribution of Gamma(X) for these CSOs closely resembles that observed in a sample of radio-loud quasars and low-excitation radio galaxies (RGs). In the radio-X-ray luminosity panel, these CSOs exhibit a distribution more akin to FR I RGs than FR II RGs, characterized by higher luminosities. The positive correlation between Gamma(X) and the Eddington ratio, which has been noted in radio-quiet active galactic nuclei, is not observed in these CSOs. These findings suggest that although the contribution of the disk-corona system cannot be completely ruled out, jet/lobe radiation likely plays a dominant role in the X-ray emission of these CSOs.