X-ray heating and ionization of broad-emission-line regions in QSO's and active galaxies

Technical Report · Tue Jul 01 04:00:00 EDT 1980

DOI:https://doi.org/10.2172/5219477· OSTI ID:5219477

Weisheit, J C; Shields, G A; Tarter, C B

Absorption of x-rays deep within the broad-line emitting clouds in QSO's and the nuclei of active galaxies creates extensive zones of warm (T approx. 10/sup 4/K), partially ionized N/sub e//N approx. 0.1) gas. Because Lyman alpha photons are trapped in these regions, the x-ray energy is efficiently channeled into Balmer lines collisionally excited from the n = 2 level. The HI regions plus the HII regions created by ultraviolet photons illuminating the surfaces of the clouds give rise to integrated L..cap alpha../H..cap alpha.. line emission ratios between 1 and 2. Enhanced MgII line emission from the HI regions gives rise to integrated MgII/H..cap alpha.. ratios near 0.5. The OI line lambda 8446 is efficiently pumped by trapped H..cap alpha.. photons and in the x-ray heated zone an intensity ratio I (lambda 8446)/I(H..cap alpha..) approx. < 0.1 is calculated. All of these computed ratios now are in agreement with observations.

• Research Organization: Princeton Univ., NJ (USA). Plasma Physics Lab.
• DOE Contract Number: AM02-76CH03073
• OSTI ID: 5219477
• Report Number(s): PPPL-1683
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics &amp; Cosmology-- Quasi-Stellar
Radio
&amp; X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION SPECTRA
BALMER LINES
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
EMISSION SPECTRA
H1 REGIONS
IONIZATION
IONIZING RADIATIONS
LYMAN LINES
QUASARS
RADIATIONS
SPECTRA
X RADIATION
X-RAY SPECTRA