BAT AGN Spectroscopic Survey - V. X-ray properties of the Swift/BAT
  70-month AGN catalog
  Hard X-ray ($\geq 10$ keV) observations of Active Galactic Nuclei (AGN) can
shed light on some of the most obscured episodes of accretion onto supermassive
black holes. The 70-month Swift/BAT all-sky survey, which probes the 14-195 keV
energy range, has currently detected 838 AGN. We report here on the broad-band
X-ray (0.3-150 keV) characteristics of these AGN, obtained by combining
XMM-Newton, Swift/XRT, ASCA, Chandra, and Suzaku observations in the soft X-ray
band ($\leq 10$ keV) with 70-month averaged Swift/BAT data. The non-blazar AGN
of our sample are almost equally divided into unobscured ($N_{\rm H}<
10^{22}\rm cm^{-2}$) and obscured ($N_{\rm H}\geq 10^{22}\rm cm^{-2}$) AGN, and
their Swift/BAT continuum is systematically steeper than the 0.3-10 keV
emission, which suggests that the presence of a high-energy cutoff is almost
ubiquitous. We discuss the main X-ray spectral parameters obtained, such as the
photon index, the reflection parameter, the energy of the cutoff, neutral and
ionized absorbers, and the soft excess for both obscured and unobscured AGN.
