1. How Massive Is Supermassive
How Massive Is Supermassive? Measuring the Masses of Supermassive Black Holes
Dr. Catherine (Kate) Grier, the Pennsylvania State University
Cell:
Collaborators: Jonathan Trump (UConn), Yue Shen (UIUC), Niel Brandt (Penn State), Ian McGreer (Arizona), Pat Hall (York), Keith Horne (St. Andrews)
and the SDSS Reverberation Mapping Collaboration

2. Supermassive Black Hole Masses
Most massive galaxies are thought to host supermassive black holes (SMBHs) in their centers.
Relationships are found between SMBH mass and galaxy
Possibly indicates a connection between SMBH growth and galaxy growth
In nearby galaxies, SMBH masses are measured from the motions of stars or gas near the center of the galaxy.
In more distant galaxies, we use active galactic nuclei, or quasars, to measure masses.
Specifically, we use “Reverberation Mapping”

3. Reverberation Mapping (RM)
Uses variability in active galaxies
Light “reverberates” outwards in disk
Until now, only ~60 relatively nearby objects total have RM measurements.
RM is very observationally intensive!
Image Credit: Nahks Tr’Ehnl

4. The SDSS Reverberation Mapping Project
Multi-object reverberation campaign with the Sloan Digital Sky Survey telescope
Observing 849 quasars at the same time
Accompanying observations with CFHT telescope (Hawaii) and Bok telescope (Kitt Peak)
Began in 2014, still ongoing
The main goal: Pioneer “industrial scale” reverberation mapping --- black hole masses for ~ quasars at large distances
Image credits: David Kirkby

5. Our Results
Based on the first year of data, we measured black hole masses for 44 quasars
These quasars are much farther away than most of the other active galaxies that have been reverberation-mapped.
This is the largest sample of measurements ever to be done at once.
Image credit: Grier et al. (2017)

6. Summary
We have measured black hole masses via reverberation mapping in more quasars at larger distances than ever before.
We are starting to push out toward the era of prime SMBH growth in the Universe!
Our work increases the sample of reverberation-mapped objects by two-thirds (from about 60 to about 100).
This work paves the way for future industrial-scale reverberation mapping projects (e.g., SDSS-V, LSST)
Measurements like these will inform future simulations and investigations of SMBH and galaxy evolution

7. Thank you! This work has been published by the Astrophysical Journal:
Grier et al. (2017, ApJ, 851, 21)
A poster presenting this work can be found tomorrow (January 10) in the AGN, QSOs and Blazars Poster Session.
Poster #250.25
Catherine J. Grier, Pennsylvania State University