The Sloan Digital Sky Survey Reverberation Mapping Project: The M BH–Host Relations at 0.2 ≲ z ≲ 0.6 from Reverberation Mapping and Hubble Space Telescope Imaging

AbstractSNe Ia are currently providing the most direct measurements of the accelerated expansion of the Universe and also put constraints on the nature and evolution of the so-called ‘dark energy’. Despite major efforts to increase the number of known high-redshift SNe Ia with reliable distance estimates, two regions in the Hubble diagram remain only sparsely observed. At redshifts z > 1 the limitations of ground-based instruments require the Hubble Space Telescope and its superior angular resolution to get meaningful distance estimates, while at intermediate redshifts (z ≃ 0.2) the large solid angle necessary presents an obstacle to most surveys that can be overcome with the Sloan Digital Sky Survey, SDSS-II.

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Space Telescope and Optical Reverberation Mapping Project: A Leap Forward in Reverberation Mapping

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316012680 ◽

2016 ◽

Vol 12 (S324) ◽

pp. 215-218 ◽

Cited By ~ 1

Author(s):

Bradley M. Peterson

Keyword(s):

World Wide ◽

Hubble Space Telescope ◽

Line Emission ◽

Broad Line ◽

Space Telescope ◽

Reverberation Mapping ◽

Significant Challenge ◽

Past Behavior ◽

Line Region ◽

Mapping Program

AbstractIn 2014, a 179-orbit allocation of Hubble Space Telescope time anchored a massive reverberation-mapping program on the well-studied Seyfert 1 galaxy NGC 5548. Supporting imaging and spectrophotometric observations were provided by Swift, Chandra, Spitzer, and a world-wide network of ground-based telescopes. Understanding the data remains a significant challenge, partly because the level of detail is far beyond what has been seen before and partly because the behavior of the AGN was not typical of its past behavior. Based on analysis to date, the following conclusions can be reached: (1) the AGN accretion disk has a temperature profile that is consistent with that predicted by the Shakura–Sunyaev model, but is about three times larger than expected; (2) at least part of the broad-line region appears to be a Keplerian disk seen at intermediate inclination, and (3) the broad-line emission response from the far side of the disk is weaker than expected.

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Identifying Circumgalactic Medium Absorption in QSO Spectra: A Bayesian Approach

The Astrophysical Journal ◽

10.3847/1538-4357/ac2954 ◽

2021 ◽

Vol 923 (1) ◽

pp. 44

Author(s):

Jennifer E. Scott ◽

Emileigh S. Shoemaker ◽

Colin D. Hamill

Keyword(s):

Bayesian Methods ◽

Statistical Approach ◽

Hubble Space Telescope ◽

Spectroscopic Studies ◽

Photometric Data ◽

Sloan Digital Sky Survey ◽

Sky Survey ◽

The Galaxy ◽

Circumgalactic Medium

Abstract We present a study of candidate galaxy–absorber pairs for 43 low-redshift QSO sightlines (0.06 < z < 0.85) observed with the Hubble Space Telescope/Cosmic Origins Spectrograph that lie within the footprint of the Sloan Digital Sky Survey with a statistical approach to match absorbers with galaxies near the QSO lines of sight using only the SDSS Data Release 12 photometric data for the galaxies, including estimates of their redshifts. Our Bayesian methods combine the SDSS photometric information with measured properties of the circumgalactic medium to find the most probable galaxy match, if any, for each absorber in the line-of-sight QSO spectrum. We find ∼630 candidate galaxy–absorber pairs using two different statistics. The methods are able to reproduce pairs reported in the targeted spectroscopic studies upon which we base the statistics at a rate of 72%. The properties of the galaxies comprising the candidate pairs have median redshift, luminosity, and stellar mass, all estimated from the photometric data, z = 0.13, L = 0.1L *, and log ( M * / M ⊙ ) = 9.7 . The median impact parameter of the candidate pairs is ∼430 kpc, or ∼3.5 times the galaxy virial radius. The results are broadly consistent with the high Lyα covering fraction out to this radius found in previous studies. This method of matching absorbers and galaxies can be used to prioritize targets for spectroscopic studies, and we present specific examples of promising systems for such follow-up.

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