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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present an analysis of the time-averaged spectrum of the Seyfert-2 activegalaxy NGC 4388, obtained by NICER. The intrinsic strength of the reflectionspectrum in NGC 4388, the large collecting area and favorable pass band ofNICER, and a net exposure of 105.6 ks yielded an exceptionally sensitivespectrum. Using two independent families of models, the intrinsic spectrum fromthe central engine is found to be highly obscured but not Compton-thick.Enforcing physical self-consistency within each model, the independenttreatments give formally consistent results: N_H = 2.67 (-0.03,+0.02) E+23cm^-2 or N_H = 2.64 (-0.03, +0.03) E+23 cm^-2. Past measurements made withSuzaku and XMM-Newton are in broad agreement with these column density values.A more recent measurement with NuSTAR (in late 2013) recorded a column densityabout twice as large; the robustness of this variability is reinforced by theuse of consistent models and procedures. The neutral Fe K-alpha line in theNICER spectrum is nominally resolved and consistent with an origin in theoptical broad line region (BLR). The data also require ionized absorption inthe Fe K band, similar to the "warm absorbers" detected in Seyfert-1 activegalactic nuclei (AGN). The low-energy spectrum is consistent with a set ofionized plasma components. We discuss these findings and note that thegeometric inferences that derive from this analysis can be tested with XRISMand Athena.

A NICER Look at Strong X-ray Obscuration in the Seyfert-2 Galaxy NGC 4388