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Register a new userXMM-Newton observations of warm absorbers in PG quasars
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C. E. Ashton
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We present XMM-Newton EPIC observations of warm absorbers in the quasars PG 1114+445 and PG 1309+355, both of which exhibit evidence for absorption by warm material in the line-of-sight. We find the absorption in PG 1114+445 to be in two phases, a `hot phase with a log ionisation parameter xi of 2.57, and a `cooler phase with log xi of 0.83; an unresolved transition array (UTA) of M-shell iron is observed in the cooler phase. The absorption in this quasar is similar to that observed in the Seyfert 1 NGC 3783. The absorption in PG 1309+355 consists of a single phase, with log xi of 1.87. The absorbing gas lies at distances of 10^{18} - 10^{22} cm from the continuum radiation sources in these AGN, which suggests that it could originate in a wind emanating from a molecular torus. We derive distances assuming that these X-ray warm absorbers have the same velocity as the UV warm absorbers observed in these quasars. The distances to the warm absorbers from the central continuum source scale approximately with the square root of the AGN ionising luminosity, a result consistent with the warm absorber originating as a torus wind. The kinetic luminosities of these outflowing absorbers represent insignificant fractions (< 10^{-3}) of the energy budgets of the AGN.
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