X-ray Emission Study of TeV Blazars

In this work, we present a systematic X-ray study of 85 TeV-detected blazars based on archival Swift-XRT and NuSTAR observations available up to May 2024. We derive unabsorbed X-ray fluxes and photon indices through spectral fitting, and investigate their light curves, spectral energy distributions, flux distributions, power spectral densities, and flux-index correlations. Using the fractional variability method, we identify 78 sources as variable in the soft X-ray band and 14 sources as variable in the hard X-ray band. For well-sampled soft X-ray light curves, the flux distributions are generally better described by log-normal functions, while the PSD slopes span βPSD=0.1--$1.6$, with most values between 1.0 and 1.6, where the PSD is defined as P(f)∝ f^-βPSD. We find positive correlations between TeV and X-ray luminosities, supporting a leptonic emission scenario. We also find a correlation between X-ray and disk luminosities, whereas no significant correlation is found between X-ray luminosity and black hole mass.