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 analyze the Chandra X-ray spectrum obtained with the HETGS gratingspectrometer of IRAS 13349+2438, which has one of the richest absorptionspectra of a quasar outflow. Absorption from almost all charge states of Fe isdetected. This allows for a detailed reconstruction of the absorption measuredistribution (AMD), which we define as the continuous distribution of columndensity as a function of ionization parameter. We find a double peaked AMD forIRAS 13349+2438 with a total (ionized) column density of N_H = (1.2 +- 0.3)*10^{22} cm^-2} assuming solar iron abundance. For comparison, we perform asimilar analysis on the well studied HETGS spectrum of NGC 3783. Both sourcesfeature a deep minimum in column density consistent with no absorption from gasat temperatures of 4.5 < log T < 5 (K). We interpret the minima asobservational evidence for thermal instability in this temperature regime.Comment: 25 pages, 7 figure

Absorption Measure Distribution of the Outflow in IRAS 13349+2438: Direct Observation of Thermal Instability?