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Date and Time of the Query: 2019-08-18 T13:18:16 PDT
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For refcode 2012MNRAS.423..600S:
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Copyright by Royal Astronomical Society. 2012MNRAS.423..600S Type 1 AGN at low z- I. Emission properties Stern, Jonathan; Laor, Ari Abstract. We analyse the emission properties of a new sample of 3579 type 1 AGN, selected from Sloan Digital Sky Survey (SDSS) Data Release 7 based on the detection of broad Halpha emission. The sample extends over a broad Halpha luminosity L_bHalpha_ of ? and a broad Halpha full width at half-maximum (FWHM) of ?, which covers the range of black hole mass 10^6^ < M_BH_/M_sun_ < 10^9.5^ and luminosity in Eddington units 10^-3^ < L/L_Edd_ < 1. We combine ROSAT, GALEX and 2MASS observations to form the spectral energy distribution (SED) from 2.2 ?m to 2 keV. We find the following. (1) The distribution of the Halpha FWHM values is independent of luminosity. (2) The observed mean optical-ultraviolet (optical-UV) SED is well matched by a fixed-shape SED of luminous quasars, which scales linearly with L_bHalpha_, and a host galaxy contribution. (3) The host galaxy r-band (fibre) luminosity function follows well the luminosity function of inactive non-emission-line galaxies (NEGs), consistent with a fixed fraction of ~3 per cent of NEGs hosting an AGN, regardless of the host luminosity. (4) The hosts of lower luminosity AGN have a mean z-band luminosity and u-z colour which are identical to NEGs with the same redshift distribution. With increasing L_bHalpha_ the AGN hosts become bluer and less luminous than NEGs. The implied increasing star formation rate with L_bHalpha_ is consistent with the relation for SDSS type 2 AGN of similar bolometric luminosity. (5) The optical-UV SED of the more luminous AGN shows a small dispersion, consistent with dust reddening of a blue SED, as expected for thermal thin accretion disc emission. (6) There is a rather tight relation between ? and L_bHalpha_, which provides a useful probe for unobscured (true) type 2 AGN. (7) The primary parameter that drives the X-ray to UV emission ratio is luminosity, rather than M_BH_ or L/L_Edd_. Key words: quasars: emission lines, quasars: general
Retrieve 6277 NED objects in this reference.
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