* Astronomy

Title: 1ES 1927+654: a bare Seyfert 2
Authors: L. C. Gallo (1), C. MacMackin (1), R. Vasudevan (2), E. M. Cackett (3), A. C. Fabian (4), F. Panessa (5) ((1) Saint Mary's Univ. (2) Univ. of Maryland (3) Wayne State Univ. (4) IoA (5) IASF-INAF)

1ES 1927+654 is an active galactic nucleus (AGN) that appears to defy the unification model. It exhibits a type-2 optical spectrum, but possesses little X-ray obscuration. XMM-Newton and Suzaku observations obtained in 2011 are used to study the X-ray properties of 1ES 1927+654. The spectral energy distribution derived from simultaneous optical-to-X-ray data obtained with XMM-Newton shows the AGN has a typical Eddington ratio (L/L_Edd = 0.014-0.11). The X-ray spectrum and rapid variability are consistent with originating from a corona surrounding a standard accretion disc. Partial covering models can describe the x-ray data; however, the narrow Fe Ka emission line predicted from standard photoelectric absorption is not detected. Ionised partial covering also favours a high-velocity outflow (v ~ 0.3c), which requires the kinetic luminosity of the wind to be >30 per cent of the bolometric luminosity of the AGN. Such values are not unusual, but for 1ES 1927+654 it requires the wind is launched very close to the black hole (~ 10 Rg). Blurred reflection models also work well at describing the spectral and timing properties of 1ES 1927+654 if the AGN is viewed nearly edge-on, implying that an inner accretion disc must be present. The high inclination is intriguing as it suggests 1ES 1927+654 could be orientated like a Seyfert 2, in agreement with its optical classification, but viewed through a tenuous torus.

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