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Non-steady state line locking in broad absorption line quasi-stellar objects

1989; IOP Publishing; Volume: 342; Linguagem: Inglês

10.1086/167578

1538-4357

Erez Braun, Mordehai Milgrom,

Spectroscopy and Laser Applications

view Abstract Citations (28) References (14) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Non--Steady State Line Locking in Broad Absorption Line Quasi-stellar Objects Braun, Erez ; Milgrom, Mordehai Abstract A simple, non-steady state mechanism for absorption-absorption line locking (hereafter LL) is proposed. In contrast to LL in steady state flows which have been discussed so far, this mechanism does not require that the locked line radiation pressure contributes substantially to the outward forces; neither does it require that the outward (radiation) force is almost countervailed by an inward force (e.g., gravity). All that is needed is that the net acceleration of the (locked) downstream gas element be in a small excess relative to the upstream element to which it is locked. Locking is effective when this acceleration excess is smaller than the line contribution to the acceleration. Some of the broad-absorption-line QSOs exhibit narrow absorption lines, superposed on the broad absorption troughs that thought to be locked in velocity space. Line doublets appear multiply in the spectrum with Doppler velocity differences which correspond to the frequency difference of the doublet. This observation may be explained by the above mechanism. Publication: The Astrophysical Journal Pub Date: July 1989 DOI: 10.1086/167578 Bibcode: 1989ApJ...342..100B Keywords: Absorption Spectra; Computational Astrophysics; Quasars; Radiative Transfer; Cosmic Gases; Gravitational Effects; Luminosity; Radiation Pressure; Spectral Line Width; Astrophysics; QUASARS; RADIATIVE TRANSFER full text sources ADS | data products SIMBAD (4) NED (3)