QSO Absorption Research Articles

Emission-line objects near QSO absorbers. II - Analysis and implications of star-forming objects at moderate redshift

view Abstract Citations (29) References (41) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Emission-line objects near QSO absorbers. II. Analysis and implications of star-forming objects at moderate redshift. Yanny, Brian Abstract A sample of 37 candidate star-forming emission objects at z between 0.4 and 1.2 selected by Yanny et al. (1990) on the basis of narrow-band imaging are analyzed in the context of interpreting their emission as indicators of star formation at the redshift of the absorber. Results of long-slit spectroscopy verify that four of these candidate objects have emission flux at the wavelengths predicted. Two objects (0235 + 164 object C and 0119 - 046 object 70) were shown to be at the redshift of their respective absorbers by detection of two or more lines. The other two (0420 - 014 object 43 and 0119 - 046 object 15) are one-line redshifts, but the FWHMs of these two lines, 270 km/sec and 310 km/sec, respectively, are consistent with a nearly resolved forbidden O II emission-line doublet. Publication: The Astrophysical Journal Pub Date: March 1990 DOI: 10.1086/168474 Bibcode: 1990ApJ...351..396Y Keywords: Emission Spectra; Quasars; Star Formation; Bl Lacertae Objects; Galactic Evolution; Red Shift; Astrophysics full text sources ADS | data products NED (12) SIMBAD (8) Related Materials (2) Part 1: 1990ApJ...351..377Y Part 3: 1992ApJ...391..569Y

Two-point correlation function of QSO metal absorption systems from an inhomogeneous catalog of observations

A model has been constructed for the selection and evolutionary effects present in a population of QSO metal-line absorption redshift systems taken from a large catalog of data collected under various conditions. For all but a small subset of the systems, the model is shown to be successful in describing these effects. The model is then used in constructing the two-point correlation function of QSO metal absorbers over the range of comoving separation up to 1200h Mpc (h = H0/10 km s MPc ). Since this correlation function is computed using only the pairing of absorbers in different lines of sight to QSOs, as opposed to studies of pairing in the same line of sight, it should contain correlation due only to spatial clustering and not to velocity clustering. Evident in this correlation function are (1) a signal at separations less than 1h Mpc (on a ''fixed scale'' unchanging in redshift) corresponding to a population of objects with a number density similar to that of Zwicky galaxy clusters, and (2) a two-point function beyond 1h Mpc consistent wiht no correlation. This result may be consistent with the lack of correlation already seen in Ly -only QSO absorbers, even if bothmore » types of systems have similar spatial correlation functions. A general technique for collecting a more useful body of data for testing hypotheses regarding large-scale structure and cosmology is suggested.« less