quasar host galaxies: growing up with monstrous middles kim k. mcleod, wellesley college george...
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Quasar Host Galaxies:Growing up with Monstrous
Middles
Kim K. McLeod, Wellesley College
George Rieke, U. of ArizonaLisa Storrie-Lombardi, IPACBrian McLeod, CfAJill Bechtold, U. of Arizona
McLeod/Scientific American
Hosts, in the style of Astro101(“’Scopes for dopes?”)
1984: “In a few quasars, we can actually observe the underlying galaxies in which they are embedded…” (Abell, Realm of the Universe)
1994: “It is very difficult to observe the ‘host galaxy’”
Radio quiet = spiral; Radio loud = elliptical(Kaufmann, Universe)
2004: “Quasars turn out to be located in the centers of galaxies (!)…both spiral and elliptical…many involved in a collision.”
(Fraknoi, Morrison, & Wolff, Voyages)
Why can’t grown astronomers tell a spiral from an elliptical?
(even our C students can do this…)
Argument by Analogy
Galaxy Gallery
Spirals
Elliptical
Merger and ULIRGSTScI
Wellesley students
Why we care (deeply!)
We have met the enemy…
Hosts on the eve of HSTOur program:
--256x256 IR camera
--image 50 z<0.4 quasars and 50 Seyferts
Simultaneous with similar study by Dunlop et al.:--nicely matched samples of RLQ, RQQ, and RG--later got WFPC2 data
IR images from ground
Quasars (what kind of galaxies ARE they???)
Seyferts (obviously spirals, and some perfectly normal)
K. McLeod/PASP
“Which of these things is not like the other?”
K. McLeod/Sky&Telescope with thanks to John Bahcall
WFPC2 on patrol!
Bahcall et al. WFPC2 post PSF subtraction
FINALLY BEAUTIFUL FUZZ!
Only some of these look normal…and RQQ can live in ellipticals.
Examples of NICMOS images of z<0.4 hostsMcLeod & McLeod 2000
Sing “Ho” for the H-band…good for tracing stellar mass but NOT the best place to look for spiral arms.
(z<0.4)Quasars follow the BH-bulge relation* and accrete at ~10% Eddington (by product: luminous RQQ often in ellipticals)
*some BH masses measured by reverb mapping or virialized emission lines…
Growing up with a monster in the middle
Kauffmann & Haehnelt 2000
Hierarchical structure formation: black holes are fueled, and galaxies grow, through mergers
Z=0.4
Z=3
Ridgway, Heckman, Calzetti, & Lehnert 2002
Hutchings et al. 2002
Kukula et al. 2001, with black hole masses from virialized MgII
HST at z=2-3
Taking the big step to high-z: Do PANIC!
Bechtold and McLeod have been using Magellan (6.5m) and Gemini (8m) to image z=4 quasars in the near-IR
Martini, Regan,
Mulchaey, & Pogge
2003
“A Moon a
minute”—P.
Martini
HST and Seyferts: feeding the monster
Astro101 Revisited2014: “In 2009, HST observations of
large samples of hosts (from SDSS samples?)fuzz around z=4 quasarslensed quasars at high zelemental abundances in high-z quasarsthe nuclei of dwarf galaxies…(insert your favorites here)…
showed how stars and black holes grow together starting from a seed masses of _______ inside dark matter halos to make the galaxies we see today.”
H S To
o !
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