Expanded Iron UTA spectra -- probing the thermal stability limits in AGN clouds

Abstract

The Fe unresolved transition array (UTAs) produce prominent features in the 15-17?A wavelength range in the spectra of Active Galactic Nuclei (AGN). Here we present new calculations of the energies and oscillator strengths of inner- shell lines from Fe XIV, Fe XV, and Fe XVI. These are crucial ions since they are dominant at inflection points in the gas thermal stability curve, and UTA excitation followed by autoionization is an important ionization mechanism for these species. We incorporate these, and data reported in previous papers, into the plasma simulation code Cloudy. This updated physics is subsequently employed to reconsider the thermally stable phases in absorbing media in Active Galactic Nuclei. We show how the absorption profile of the Fe XIV UTA depends on density, due to the changing populations of levels within the ground configuration.

ApJ in press

References in corpus (2)

• Radiative cooling in collisionally and photo ionized plasmas
• Dielectronic recombination and stability of warm gas in AGN

Cited by in corpus (9)

• Modelling the nebular emission from primeval to present-day star-forming galaxies
• Nuclear activity versus star formation: emission-line diagnostics at ultraviolet and optical wavelengths
• GASP III. JO36: a case of multiple environmental effects at play?
• Multiphase AGN winds from X-ray irradiated disk atmospheres
• Radiation Pressure Confinement -- III. The origin of the broad ionization distribution in AGN outflows
• Detection of the self-regulation of star formation in galaxy discs
• The Decline and Fall of the Youngest Planetary Nebula
• A quantitative demonstration that stellar feedback locally regulates galaxy growth
• Extended coronal line emission and new clues to a possible dual AGN in the merger J1356+1026