The Soft-X-Ray Spectral Shape of X-Ray-Weak Seyferts

(I) We observed eight Seyfert~2s and two X–ray–weak Seyfert~1/QSOs with the ROSAT PSPC, and one Seyfert~2 with the ROSAT HRI. These targets were selected from the Extended 12\um\ Galaxy Sample. (II) Both Seyfert~1/QSOs vary by factors of 1.5—2. The photon indices steepen in the more luminous state, consistent with the variability being mainly due to the softest X–rays, which are confined to a size of less than a parsec. (III) Both the Seyfert~2s and Seyfert~1/QSOs are best fit with a photon index of $\mathrm{\Gamma }\sim 3$, which is steeper than the canonical value of $\mathrm{\Gamma }\sim 1.7$ measured for X–ray–strong Seyferts by ROSAT and at higher energies. Several physical explanations are suggested for the steeper slopes of X–ray–weak objects. (IV) We observed one Seyfert~2, NGC~5005, with the ROSAT HRI, finding about 13% of the soft X–rays to come from an extended component. This and other observations suggest that different components to the soft X–ray spectrum of some, if not all, X–ray–weak Seyferts may come from spatially distinct regions.