Thursday. Packed my stuff all morning; it's now 3pm and I'm finally ready for work. Tomorrow is travel and Hot Springs! I'll be Home Saturday.
Friday. Only read one abstract yesterday, but didn't write the summary. Continuing with writing on the train, on my way to Busan on KTX, with free WiFi.
1107.4372
The Demographics of broad-line quasars in the mass-luminosity plane. I. Testing FWHM-based virial black hole masses
Shen, Kelly
Use 58k uniformly selected quasars from SDSS DR7 at z~0.4-5 to jointly constrain the LF and BHMF via description of underlying active BHMF and Eddington ratio distribution to match the observed distribution in the quasar mass-luminosity plane. Systematics considered: selection effect of the sample flux limit, statistical scatter between true BH masses and FWHM-based single-epoch virial mass estimates, potential luminosity-dependent biases of these mass estimates. LF is tightly constrained, and makes reasonable predictions 3 mags fainter than the SDSS flux limit, but the BHMF is unconstrained at z>0.7 because of the unknown dependencies/biases of the BH mass obtained from estimators, and the scarcity of the high-z objects (but some bias estimated--estimated mass probably biased high by a factor of few at z > 0.7). Some evidence of "downsizing" in BHMF. BH mass density in broad-line quasars insignificant compare to the total BH mass density at all times. No strong BH mass dependence on mean Eddington ratio, but evidence for increased mean Eddington ratio (at fixed BH mass) with redshift.
* what is "downsizing"? I always ask and hear the answer, and I always forget.
* what is the mass-luminosity plane for quasars?
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