X-ray properties of high redshift, optically selected QSOs

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5684605

Anderson, S F

In order to study the x-ray properties of high redshift QSOs, the author took grism/grens plates covering 17 deg./sup 2/ of sky previously imaged to very sensitive x-ray flux levels with the Einstein Observatory. Following optical selection of the QSO, the archived x-ray image was examined to extract an x-ray flux detection or a sensitive upper limit. Two samples of grism/grens selected QSOs are emphasized. The first, sample C, is a approx. = 80% complete sample of 37 QSOs with 1.8 less than or equal to z less than or equal to 3.0, and B less than or equal to 19.5. Using two statistical approaches that also incorporate information contained in x-ray nondetections (survival analysis and stacking), it is inferred from sample C data that such QSOs contribute <3% to the diffuse x-ray background (XRB). The contribution of all QSOs with B less than or equal to 19.5 to the XRB is found to be 21 +/- 8%. Through the use of complete samples, very few uncertain parameters or extrapolations are used in these determinations. The second sample, sample N, includes 78 QSOs that occupy a narrow region of redshift (z) and optical luminosity (L/sub opt/) space. The x-ray to optical luminosity ratio is parameterized by a hypothetical power law slope, ..cap alpha../sub ox/, connecting the two wavebands, and is thought to depend on L/sub opt/ and/or z. Sample N occupies a sufficiently narrow region of L/sub opt/-z space that ensemble mean parameters can be directly determined without the need to correct for such dependences.

• Research Organization: Washington Univ., Seattle (USA)
• OSTI ID: 5684605
• 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
BACKGROUND RADIATION
COSMIC RADIO SOURCES
LUMINOSITY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASARS
RADIATIONS
RED SHIFT
SPECTRA
X-RAY SPECTRA