Spectral line

Equivalent width

Spectroscopy

Quantum mechanics

Redshift

Galaxy

Spectrograph

Astrophysics

Absorption (acoustics)

Quasar

Physics

Ionization

Mathematics

Optics

Astronomy

Telescope

Halo

Metallicity

Geometry

Emission spectrum

Radial velocity

Stars

Absorption spectroscopy

Line (geometry)

The Astrophysical Journal

view Abstract Citations (34) References (20) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Splitting of C IV lines in a QSO absorption-line system. York, D. G. ; Green, R. F. ; Bechtold, J. ; Chaffee, F. H., Jr. Abstract The C IV doublet in the z = 1.795 absorption-line system in the QSO B2 1225 + 317 has been observed with the Multiple Mirror Telescope echelle spectrograph at a resolution of 10 km/s. The profile of C IV, previously known to contain at least three velocity components, is shown to consist of at least eleven. Individual components have Doppler width upper limits of 6.4-13.2 km/s. These low upper limits, plus a study of published profile shapes for several other species, suggest that the observed gas is not in an equilibrium state of collisional ionization, and that electron temperatures are 35,000 K or lower. The width of the aggregate profile (approximately 500 km/s) is larger by a factor of 5 than any C IV or Si IV profile observed through the halo of the Galaxy, while individual components are narrower than those in the Galaxy. Thus, intervening galaxies with halos similar to that of the Galaxy, even if occurring in groups, may not explain this QSO absorption-line system. Publication: The Astrophysical Journal Pub Date: May 1984 DOI: 10.1086/184256 Bibcode: 1984ApJ...280L...1Y Keywords: Astronomical Spectroscopy; Carbon; Gas Ionization; Quasars; Spectral Line Width; Absorption Spectra; Metallicity; Red Shift; Astronomy full text sources ADS | data products SIMBAD (1) NED (1)

Splitting of C IV lines in a QSO absorption-line system