24 citations · 90 across the 8 of their papers we have counts for
8 papers
Transient obscuration event captured in NGC 3227 IV. Origin of the obscuring cloud variability
S. Grafton-Waters, J. Mao, M. Mehdipour +13
Obscuration events in type I active galactic nuclei (AGN) have been detected more frequently in recent years. The strong flux decrease in the soft X-ray band between observations h…
Detection of an Unidentified Soft X-ray Emission Feature in NGC 5548
Liyi Gu, Junjie Mao, Jelle S. Kaastra +17
NGC~5548 is an X-ray bright Seyfert 1 active galaxy. It exhibits a variety of spectroscopic features in the soft X-ray band, including in particular the absorption by the AGN outfl…
Transient obscuration event captured in NGC 3227 III. Photoionization modeling of the X-ray obscuration event in 2019
Junjie Mao, J. S. Kaastra, M. Mehdipour +16
A growing number of transient X-ray obscuration events in type I AGN suggest that our line-of-sight to the central engine is not always free. Multiple X-ray obscuration events have…
A Study of the Soft X-ray Emission Lines in NGC 4151 II. The Internal Plasma Properties
S. Grafton-Waters, W. Dunn
We showcase a tool suite that enables the fitting of soft X-ray spectra in active galactic nuclei (AGN), without the need for specialist software, allowing access to AGN physics fo…
Transient obscuration event captured in NGC~3227 II. Warm absorbers and obscuration events in archival XMM-Newton and NuSTAR observations
Yijun Wang, Jelle Kaastra, Missagh Mehdipour +18
The relation between warm absorber (WA) outflows of AGN and nuclear obscuration activities caused by optically-thick clouds (obscurers) crossing the line of sight is unclear. NGC 3…
A Study of the Soft X-ray Emission Lines in NGC 4151 I. Kinematic Properties of the Plasma Wind
S. Grafton-Waters, M. Ahmed, S. Henson +6
We present our analysis of the narrow emission lines produced in the plasma regions within the bright active galactic nucleus of NGC 4151, from an ORBYTS research-with-schools publ…
Transient obscuration event captured in NGC 3227. I. Continuum model for the broadband spectral energy distribution
M. Mehdipour, G. A. Kriss, J. S. Kaastra +21
From Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton…
Photoionisation Modelling of the X-ray Emission Line Regions within the Seyfert 2 AGN NGC 1068
S. Grafton-Waters, G. Branduardi-Raymont, M. Mehdipour +4
We investigate the photoionised X-ray emission line regions (ELRs) within the Seyfert 2 galaxy NGC 1068, to determine if there are any characteristic changes between observations t…