English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We analyse 400 ks of XMM-Newton data on the active galactic nucleus NGC 1365using principal component analysis (PCA) to identify model independent spectralcomponents. We find two significant components and demonstrate that they arequalitatively different from those found in MCG?6-30-15 using the same method.As the variability in NGC 1365 is known to be due to changes in the parametersof a partial covering neutral absorber, this shows that the same mechanismcannot be the driver of variability in MCG-6-30-15. By examining intervalswhere the spectrum shows relatively low absorption we separate the effects ofintrinsic source variability, including signatures of relativistic reflection,from variations in the intervening absorption. We simulate the principalcomponents produced by different physical variations, and show that PCAprovides a clear distinction between absorption and reflection as the driversof variability in AGN spectra. The simulations are shown to reproduce the PCAspectra of both NGC 1365 and MCG-6-30-15, and further demonstrate that thedominant cause of spectral variability in these two sources requires aqualitatively different mechanism.

PCA of PCA: Principal Component Analysis of Partial Covering Absorption in NGC 1365