1. Mike Brotherton: HST Images of Post-Starburst Quasars
Hubble Space Telescope Images of Post-Starburst Quasars: Galaxy/Black Hole Evolution in Action
Mike Brotherton
University of Wyoming
Mobile Phone:
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

2. Mike Brotherton: HST Images of Post-Starburst Quasars
Hubble images
Red light images, about 120 thousand light-years on a side (10 arcseconds), of 29 post-starburst quasars, some 3.5 billion light-years away, chosen by spectral signatures of quasars and starbursts of a few hundred million years of age.
Predominantly interacting systems, with nearby companions, double nuclei tidal tails, disturbances, and evidence of recent mergers (e.g., shells).
Chosen from spectra.
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

3. Spectra of Stars, Spectra of Quasars
Average quasar, from Brotherton et al. (2001)
Stars from Horizons by Seeds
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

4. A Prototype Post-Starburst Quasar
Late 1990s, UN J (Brotherton et al. 1999, ApJ, 520, L87)
About 7 billion light years distant
Rare
Identified by the spectrum
Broad emission lines of a quasar
Balmer jump feature and Balmer absorption lines from stellar population about 400 million years old and more than ten billion solar masses (the Milky Way is on order of a hundred billion solar masses)
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

5. A Prototype Post-Starburst Quasar
Keck Observatory imaging in the near-infrared (K-band)
Extended, disturbed appearance, with a companion galaxy
Some shallower Hubble imaging also consistent with identifying the host galaxy as a merger product
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

6. Significance to Galaxy Evolution
Long-recognized hints of a quasar-starburst connection
“M-sigma” relation, suggesting that the central black hole mass is tightly tied to the host galaxy mass and that both quantities may grow together over time
Similar evolution in quasar population and universal star formation rates, with both more common in the past and less common today
Detailed models and numerical simulations supporting hierarchical galaxy formation, observed properties of galaxies and black holes
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

7. Significance to Galaxy Evolution
Simplest Picture
Galaxy merger (e.g., two gas-rich spirals) ->
Starburst (hidden by dust) AKA luminous infrared galaxy ->
black hole is fueled and ignites as quasar, blowing out dust ->
quasar fades, leaving merged system, eventually a massive elliptical galaxy
Post-Starburst Quasar: a transition phase known as “blow out?”
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

8. Post-Starburst Quasars in the Sloan Digital Sky Survey
About spectra measured, with 600 finally selected as post-starburst quasars.
No a priori knowledge of what these objects look like in the sky. Most quasars from look like point sources (starlike) from ground-based telescopes, maybe with a little surrounding “fuzz” in high-quality images.
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

9. Mike Brotherton: HST Images of Post-Starburst Quasars
SDSS
Sloan Digital Sky Survey Image and Spectrum
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

10. Mike Brotherton: HST Images of Post-Starburst Quasars
SDSS
Sloan Digital Sky Survey Image and Spectrum
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

11. Mike Brotherton: HST Images of Post-Starburst Quasars
SDSS
Sloan Digital Sky Survey Image and Spectrum
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

12. Mike Brotherton: HST Images of Post-Starburst Quasars
Hubble images
Most post-starburst quasars seen to be interacting or merging systems
Merged galaxies present
Merging galaxies present
Pre-merger systems present
Galaxy Evolution Complex!
Much more quantitative follow-up work to be done modeling ages, masses, etc., using many more facilities
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars

13. Mike Brotherton: HST Images of Post-Starburst Quasars
Team Members
Mike Brotherton (Wyoming)
Mobile Phone:
Sabrina Cales, Zhaohui Shang, Rajib Ganguly (University of Wyoming)
Aleks Diamond-Stanic (Univ. of Arizona)
Dan Vanden Berk (Penn State)
Gabriella Canalizo (UC-Riverside)
This work is supported by NASA and the National Science Foundation.
11/28/2018
Mike Brotherton: HST Images of Post-Starburst Quasars