Browsing by Subject "gas kinematics"
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Item The M-Sigma And M-L Relations In Galactic Bulges, And Determinations Of Their Intrinsic Scatter(2009-06) Gultekin, Kayhan; Richstone, Douglas O.; Gebhardt, Karl; Lauer, Tod R.; Tremaine, Scott; Aller, Monique C.; Bender, Ralf; Dressler, Alan; Faber, S. M.; Filippenko, Alexei V.; Green, Richard; Ho, Luis C.; Kormendy, John; Magorrian, John; Pinkney, Jason; Siopis, Christos; Gebhardt, Karl; Kormendy, JohnWe derive improved versions of the relations between supermassive black hole mass (MBH) and host-galaxy bulge velocity dispersion (sigma) and luminosity (L; the M-sigma and M-L relations), based on 49 M-BH measurements and 19 upper limits. Particular attention is paid to recovery of the intrinsic scatter (epsilon(0)) in both relations. We find log(M-BH/M-circle dot) = alpha + beta log(sigma/ 200 km s(-1)) with (alpha, beta, epsilon(0)) = (8.12 +/- 0.08, 4.24 +/- 0.41, 0.44 +/- 0.06) for all galaxies and (alpha, beta, epsilon(0)) = (8.23 +/- 0.08, 3.96 +/- 0.42, 0.31 +/- 0.06) for ellipticals. The results for ellipticals are consistent with previous studies, but the intrinsic scatter recovered for spirals is significantly larger. The scatter inferred reinforces the need for its consideration when calculating local black hole mass function based on the M-sigma relation, and further implies that there may be substantial selection bias in studies of the evolution of the M-sigma relation. We estimate the M-L relationship as log(M-BH/M-circle dot) = alpha + beta log(L-V/10(11) L-circle dot,L- V) of (alpha, beta, epsilon(0)) = (8.95 +/- 0.11, 1.11 +/- 0.18, 0.38 +/- 0.09); using only early-type galaxies. These results appear to be insensitive to a wide range of assumptions about the measurement errors and the distribution of intrinsic scatter. We show that culling the sample according to the resolution of the black hole's sphere of influence biases the relations to larger mean masses, larger slopes, and incorrect intrinsic residuals.Item Resolving The Optical Emission Lines Of Ly Alpha Blob "B1" At Z=2.38: Another Hidden Quasar(2013-07) Overzier, Roderik A.; Nesvadba, Nesvadba P. H.; Dijkstra, M.; Hatch, N. A.; Lehnert, M. D.; Villar-Martin, M.; Wilman, R. J.; Zirm, A. W.; Overzier, Roderik A.We have used the SINFONI near-infrared integral field unit on the Very Large Telescope to resolve the optical emission line structure of one of the brightest (L-Ly alpha approximate to 10(44) erg s(-1)) and nearest (z approximate to 2.38) of all Ly alpha blobs (LABs). The target, known in the literature as object "B1", lies at a redshift where the main optical emission lines are accessible in the observed near-infrared. We detect luminous [OIII]lambda lambda 4959,5007 and H alpha emission with a spatial extent of at least 32 x 40 kpc (4 '' x 5 ''). The dominant optical emission line component shows relatively broad lines (600-800 km s(-1), FWHM) and line ratios consistent with active galactic nucleus (AGN) photoionization. The new evidence for AGN photoionization, combined with previously detected CIV and luminous, warm infrared emission, suggest that B1 is the site of a hidden quasar. This is confirmed by the fact that [OII] is relatively weak compared with [OIII] (extinction-corrected [OIII]/[OII] of about 3.8), which is indicative of a high, Seyfert-like ionization parameter. From the extinction-corrected [OIII] luminosity we infer a bolometric AGN luminosity of similar to 3x10(46) erg s(-1), and further conclude that the obscured AGN may be Compton-thick given existing X-ray limits. The large line widths observed are consistent with clouds moving within the narrow-line region of a luminous QSO. The AGN scenario is capable of producing sufficient ionizing photons to power the Ly alpha, even in the presence of dust. By performing a census of similar objects in the literature, we find that virtually all luminous LABs harbor obscured quasars. Based on simple duty-cycle arguments, we conclude that AGNs are the main drivers of the Ly alpha in LABs rather than the gravitational heating and subsequent cooling suggested by cold stream models. We also conclude that the empirical relation between LABs and overdense environments at high redshift must be due to a more fundamental correlation between AGNs (or massive galaxies) and environment.