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Profile Analysis of the Multiwavelength 2.1-year Oscillations of PG 1553+113
P. Peñil, N. Torres-Albà, A. Rico +5
We investigate the morphology of the oscillation profiles of the blazar PG~1553+113 in relation to its well-known 2.1 yr periodicity. We identify individual cycles in the …
X-ray Absorption Variability in NGC 1142: Another Constraint on the Nature of the Torus/Broad-Line Region in Active Galactic Nuclei
Isaiah S. Cox, Núria Torres-Albà, Stefano Marchesi +5
The physics, geometry, and kinematics of the gas and dust surrounding the central engine of active galactic nuclei (AGN) are not well understood. In some sources, this material obs…
The hidden variability of the torus in local Active Galactic Nuclei: 20 years of Chandra, XMM-Newton, and NuSTAR observations
Vittoria Elvezia Gianolli, Nuria Torres-Alba, Stefano Marchesi +9
X-ray absorption variability in active galactic nuclei (AGN) provides key constraints on the structure and dynamics of the circumnuclear obscuring medium, the so-called torus. A fr…
A systematic search for AGN obscuration variability in the Chandra archive
Isaiah S. Cox, Núria Torres-Albà, Stefano Marchesi +5
The nature of the obscuring material in active galactic nuclei (AGN) can be studied by measuring changes in the line-of-sight column density, , over time. This can b…
A multi-epoch X-ray study of the nearby Seyfert 2 galaxy NGC 7479: Linking column density variability to the torus geometry
Andrealuna Pizzetti, Nuria Torres-Alba, Stefano Marchesi +3
Active galactic nuclei (AGN) are powered by accreting supermassive black holes, surrounded by a torus of obscuring material. Recent studies have shown how the torus structure, form…
Compton-Thick AGN in the NuSTAR era VII. A joint NuSTAR, Chandra and XMM-Newton analysis of two nearby, heavily obscured sources
Alberto Traina, Stefano Marchesi, Cristian Vignali +11
We present the joint Chandra, XMM-Newton and NuSTAR analysis of two nearby Seyfert galaxies, NGC 3081 and ESO 565-G019. These are the only two having Chandra data in a larger sampl…