INTEGRAL and XMM-Newton spectral studies of NGC 4388

We present first INTEGRAL and XMM-Newton observations of a Seyfert galaxy, the type 2 AGN NGC 4388. Several INTEGRAL observations performed in 2003 allow us to study the spectrum in the 20 - 300 keV range. In addition two XMM-Newton observations give detailed insight into the 0.2 - 10 keV emission. Comparison with previous observations by BeppoSAX, SIGMA and CGRO/OSSE show that the overall spectrum from soft X-rays up to the gamma-rays can be described by a highly absorbed (N_H ≃ 2.8 × 10²³ cm^-2) and variable non-thermal component in addition to constant non-absorbed thermal emission (T ≃ 0.8 keV) of low abundance (∼ 5 % solar), plus a constant Fe Kα line. The hard X-ray component is well described by a simple power law with a mean photon index of Γ = 1.7. During the INTEGRAL observations the flux at 100 keV increased by a factor of 1.5. The overall data show no evidence for a cutoff up to 200 keV. The analysis of XMM-Newton data implies that the emission below 3 keV is decoupled from the AGN and probably due to extended emission as seen in Chandra observations. The constant iron line emission is apparently also decoupled from the direct emission of the central engine and likely to be generated in the obscuring material, e.g. in the molecular torus.