Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei

Details Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei

Feb 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995apj...440..606z&link_type=abstract

Astrophysical Journal v.440, p.606

Astronomy and Astrophysics

Astronomy

35

Galaxies: Active, Galaxies: Quasars: Emission Lines, Ultraviolet: Galaxies, X-Rays: Galaxies

Scientific paper

Based on HUT observations of two Seyfert 1 galaxies and lUE and HST observations of 30 QSOs, we find a correlation between the ratio of O VI λ1034 to Lyα λ1216 and the effective power-law index between 2500 Å and 2 keV: log (O VI/Lyα) = -0.74 αOX + 0.38. From X-ray-strong to weak objects the O VI/Lyα ratio decreases by a factor of ˜8. Since the ionization threshold for O VI emission is in the soft X-ray range, our finding supports photoionization models in which high-ionization emission lines are powered by extreme UV and soft X-ray photons.
Adding in ground-based optical data for 29 high-redshift QSOs, we find that, over five decades of luminosity, the O VI equivalent width shows an anti-correlation with luminosity: EW(O VI) = 4.0 × 1010 LUV-0.30, the strongest Baldwin effect among all known emission lines in AGNs. Between Seyfert 1 galaxies and high-z QSOs the equivalent widths of Lyα, C IV, and O VI decrease approximately by factors of 2, 6, and 30, respectively. The significant change in high-ionization line intensity with luminosity is consistent with the assumption that the soft X-ray continuum between 0.1 and 1 keV in high-luminosity QSOs is weaker than that in low-luminosity AGNs.

Affiliated with

Also associated with

No associations

Rating

Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relation between O VI Emission and X-Ray Intensity in Active Galactic Nuclei will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1630939