2002/01/11 by K. Horne, Keith Horne, Bradley M. Peterson +7 · 1 citation
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0201182
18 pages, 12 figures. Submitted to PASP
openalex publication_date 2002/01/11 · arxiv created 2002/01/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a series of simulations to demonstrate that high-fidelity velocity-delay maps of the emission-line regions in active galactic nuclei can be obtained from time-resolved spectrophotometric data sets like those that will arise from the proposed Kronos satellite. While previous reverberation-mapping experiments have established the size scale R of the broad emission-line regions from the mean time delay t = R/c between the line and continuum variations and have provided strong evidence for supermassive black holes, the detailed structure and kinematics of the broad-line region remain ambiguous and poorly constrained. Here we outline the technical improvements that will be required to successfully map broad-line regions by reverberation techniques. For typical AGN continuum light curves, characterized by power-law power spectra P(f) ~ f-a with a = -1.5 +/- 0.5, our simulations show that a small UV/optical spectrometer like Kronos will clearly distinguish between currently viable alternative kinematic models. From spectra sampling at time intervals Tres and sustained for a total duration Tdur, we can reconstruct high-fidelity velocity-delay maps with velocity resolution comparable to that of the spectra, and delay resolution ~2 Tres, provided Tdur exceeds the BLR crossing time by at least a factor of three. Even very complicated kinematical models, such as a Keplerian flow with superimposed spiral wave pattern, are cleanly resolved in maps from our simulated Kronos datasets. Reverberation mapping with Kronos data is therefore likely deliver the first clear maps of the geometry and kinematics in the broad emission-line regions 1-100 microarcseconds from supermassive black holes.