Kinetic Luminosity of Quasar Outflows and its Implications to AGN Feedback

31 Pages·2012·2.02 MB·English

Kinetic Luminosity of Quasar Outflows and its Implications to
AGN Feedback: HST/COS Observations
Nahum Arav
The average luminous quasar
Has sub-relativistic outflows with:
Virginia Tech
- Large scale (~1000 pc.)
Collaborators:
- Large mass flow (100 M /yr)

Doug Edmonds
- Kinetic luminosity sufficient
Benoit Burguet
for AGN feedback processes
Jerry Kriss
Max Moe

Jay Dunn
Kirk Korista
Chris Benn
Manuel Bautista
Eric Hallman
Elisa Costantini
Kentaro Aoki
In some quasars Jweet psreoeb leevmids eansc AeG oNf mfeaedsbsa ecjke catgioennt.s
- Narrow opening angle (coupling)
- Negligible mass flux per unit of
energy (~1000 times smaller than BALs)
- 20-40% of all quasars show UV absorption outflows
- Velocities: 1000-30,000 km/s
Do quasar outflows contribute significantly It will depend on their Mass
to feedback processes? flux and Kinetic luminosity
O VI
C IV
10,000 km/s
N
H
AGN
f
R
v
Kinetic luminosity of absorption outflows
1

2 3
E  m v  2fRN 1.4m v
k H p
2
Up until about 5 years ago:
2024 2
N  10 cm
H
R  0.0110000 pc
f  0.2
Exceptions: De Kool + (3 objects); Hamann 3c191
How do we go from the spectrum to
measuring the kinetic luminosity?
From absorption troughs to kinetic luminosity

• Reliable measurements of N cannot use EW, tau
ion ap
• Photoionization modeling to convert N to N and U
ion H

• Distance of the Outflow from the Central Source:

L
U 
2
n R

H

• Number Density via Troughs from metastable levels
• Fe II* UV1, UV2…; Si II* 1264, 1533… (see also poster
by Doug Edmonds)

kinetic luminosity of component C in the
SDSS 0838+2955 outflow (Moe+2009)
20.8 2
N  10 cm
Only the moderate
H
ionization phase is probed
R  3500 pc
Systematic
v  4900 km / s
uncertainties
.
45
E  2.5 10  f
1%L
ergs/s =
k 0.2
BOL
.
M  300  f Less than
0.2 Solar masses/yr 40% statistical
error
AGN feedback models need kinetic luminosity ~0.5-5%LBOL
What about the solid angle subtended by the wind?
 f  0.2  0.4
20-40% of quasars show high ionization (C IV) winds
But only 20% of all outflows show low ionization species (Dai+ 2010)