XMM - Newton Detection of a Compton - thick AGN in the 1 - Jy ULIRG / LINER F 04103 − 2838

We report on the detection of Fe Kα emission in F04103−2838, an ultraluminous infrared galaxy (ULIRG; log[LIR/L⊙] ≥ 12) that is optically classified as a LINER. Previous Chandra observations suggested the presence of both a starburst and an AGN in this source. A deeper (∼20 ksec) XMM-Newton spectrum reveals an Fe Kα line at rest frame energy ∼6.4 keV, consistent with cold neutral iron. The best-fit spectral model indicates the Fe Kα line has an equivalent width of ∼1.6 keV. The hard X-ray emission is dominated by a Compton-thick AGN with intrinsic 0.2–10 keV luminosity ∼10 ergs s, while the soft X-ray emission is from ∼0.1 keV gas attributed to the starburst. The X-ray spectrum of this source bears a striking resemblance to that of the archetypal luminous infrared galaxy NGC 6240 despite differences in merger state and infrared properties. Subject headings: galaxies: active — galaxies: starburst — galaxies: individual: F04103−2838 — X-rays: galaxies Contacting author: [email protected]