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Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar RainChandra and the Inner Structure of AGNsWarm Absorbers, X-ray Eclipses and Broad Line Region Inflows, a unification
Martin ElvisHarvard-Smithsonian Center for Astrophysics
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Chandra taught us about AGN structure
2
>100 absorption features - 6 parameter model
Chandra HETGS 850ksec spectrum of NGC 3783
AGN Wind @750 km s-1 : 2-3 phase gas in pressure equilibrium to 5%
Krongold, Nicastro, Brickhouse, Elvis, Liedahl & Mathur, 2003 ApJ 597, 832
1. X-ray Warm Absorber Outflows
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Chandra taught us about AGN structure
3
Compton ThinThickThin in 4 daysDNH>~1024cm-2 in 2 days–> ne>109 cm-3
–> R(NH) < few 1000 Rs
–> NOT the “torus” 2 days 2
days
Chandra monitoring
Risaliti et al., 2007, ApJL, 659, L111
2. Rapid eclipses by thick, cool gas clouds
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
I thought I knew AGN structure
Broad Absorption LinesReflection features
Thin Vertical wind
Narrow absorption lines X-ray `warm’ absorbersBroad High ionization Emission Lines
hollow cone
Accretion disk
Supermassive black hole
X-ray/UV ionizing continuum
Accelerating bi-conical disk wind
no absorption lines
Failed Disk wind
Broad Low ionization Emission Lines
Bi-conical Extended Narrow Line Region
Elvis 2000
Disk Winds solve everything – it’s all outflows and rotation
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
But…A Theory of Everything must explain
Every. Single. Thing.
Do Broad Line Region Inflows spoil it all?
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Reverberation Mapping
• d-function flash from quasar• Produces d-function response in an emission line from
a gas cloud at distance R • after “lag” time t=R/c
flux
Emission Line Response
R/c
flux
Central Continuum SourceFlash
time
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Isodelay Surfaces
• Parabolas of equal delay time:
• Zero delay ONLY possible on our line-of-sight to continuum
7
= r/c
= r/c
cos1
c
r
Brad Peterson, OSU
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
ARP 151
Redshifts Blueshifts
Lag
time
Broad Line Region Inflows
• Velocity Resolved Reverberation Mapping (VRRM)– Bentz et al. 2010
• Redshifts at zero lag
Infall !
Redshifts at zero lag
0
Isodelay Surfaces
Peterson 2003
Infalling gasMUST be here
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
More blueshifts at zero lag
Broad Line Region Inflows• Inflows seem to be common
– Grier et al. 2013
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Inflow leads to disks
UMBC
• Can’t fall far without angular momentum creating a disk
• Broad Line Region is not a disk:– covers ~10% of 4p– Accretion disk covers
~0.1% of 4p .
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Broad Line Region Inflow
?
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
the outflow is the inflow
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Can outflows solve Broad Line Region Inflows?
Use the Chandra results:
1. X-ray Warm Absorbers, Low Ionization Phase
Krongold et al. 2003
Log
Tem
pera
ture
Log Ionization parameter
2. X-ray Eclipsing Clouds
Schw
artz
child
radi
i
Density (cm-3)
X-ray Eclipsers
Elvis et al. 2004
BLR
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Can outflows solve Broad Line Region Inflows?
Broad Emission Line Region
Warm Absorber (LIP)*
X-ray eclipsing clouds
Temperature T(K)
(1-2) X 10(4) Few X 10(4) <10(5)
log[Densityne (cm-3)]
8 - 10 9 - 11 9 - 10
log[Ionization parameter, U]
-1.5 – 10 -3 - -1 < 100
• Same physical conditions• Same gas?• But WA is an OUTFLOW
Outflow
* LIP = Low Ionization Phase, Krongold et al. 2003
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Cool Phases in the Warm Absorber Outflow
• Found often (always?):• NCG 3783 (Krongold et al. 2003;
Netzer et al. 2003 ), • NCG 985 (Krongold et al. 2005b ,
2009 ), • NGC 4051 (Krongold et al.
2007 ), • Mrk 279 (Fields et al. 2007 ), • NGC5548 (Andráde-Velasquez et
al. 2010) 9Z
Thermal equilibrium
Log(1/Pressure)
Log(
Tem
pera
ture
)Form naturally in gas illuminated
by quasar spectrum – Krolik, McKee & Tarter 1981; Chakravorty+08,09
• High metallicity helps -- Chakravorty et al. 2012
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Cool Phase is dense
• 100 x denser than Warm Absorber: ne ~ 108 cm-2
• Column Density, NH ~ 30 x NH(WA) ≤ 1024 cm-2
• Size, d ~ 1016 cm ≈ 300 M8 Rg ≈ 60 RX-ray(M8)• Hard to accelerate• High Mass/cross-section ratio
– Mushotzky, Solomon & Strittmatter 1972– Risaliti & Elvis 2010
• Stops accelerating while warm phase continues up to escape velocity?
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Dense condensed phase, below vescape
Falls back after ~1 dynamical time ~ 1 year
= Quasar Rain
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar Rain: How quickly does it form?• Cooling time:• tcool = 1.8x1010 L0(T)/L(T) T6
1/2 ne8-1 sec.
– L(T) ~60 L0(T) Tucker 1975, Gehrels & Williams 1993
• tcool = 3 T61/2 ne8
-1 days ≈ 3 days
• Collapse time:• tsound = cs/R = 300 km s-1 / 1012.5 cm ≈ 23 days
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
How quickly does wind reach vescape?
• Acceleration time to vescape:
• tacc ~ 4M8 days (Risaliti & Elvis 2010 model)
• tcool < tacc < tsound
• Similar ballpark – competitive processes• Some condensations escape, some fall back
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Fate of the infalling rain?
• Feels ram pressure of warm outflowing gas
• Mach ~20• Strips away gas into a tail• “raindrops” destroyed• On elliptical orbits• Non-radial tails
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
We see these ablating “raindrops”• NGC1365 X-ray eclipsing clouds• NH rises fast at low covering
factor, fc
• Then NH drops as fc increases• “Cometary” tail – non-radial• Lifetime ~60 days• Cannot reach high infall velocity
Maiolino et al. 2012
Cove
ring
fact
orN
H
1 day
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar Rain
• Explains:– Infalling Broad Line Region Gas– at moderate infall velocities
• Unifies: – Broad Line Region clouds– Low Ionization X-ray Warm Absorber– X-ray eclipsing clouds– Cometary tails on X-ray eclipsing clouds
• Forms naturally• Appealing: Disk winds still solve everything
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
The Way Forward
Vikhlinin et al. 2013
×100Chandra gratings
10
0.2 0.5
Chandra HRC-LETGS
>250 X Chandra
CalorimeterA(0.5)~10,000cm2
700 X ChandraNGC3783 in 1ksec
dE ~< 5 eVR>~100 @ 0.5keVSimilar to Athena
R ~ 5000>10 X Chandra
NGC3783 spectrum in 3 ksecVariability -> density, radiusLarge Surveys: M, L/LEdd, …High z
60 km s-1
Resolves thermal line widthsTurbulence, Tthermal vs Tion
Curve of growth n(ion)Diagnostic line ratiosResolves UV-like components
Nearer term: “ARCUS” – see Randall Smith poster 8.11
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar Rain does not reach “ground”
Rain that does not reach the ground is “Virga”
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar Virga
Thank you
KWWL.com
Martin Elvis, [email protected] 15 Years of Chandra, Boston, November 2014
© H
arry
Mor
osz
Quasar Rain/Virga• Explains:
– Infalling Broad Line Region Gas– at moderate infall velocities
• Unifies Chandra and reverberation results: – Broad Line Region clouds– Low Ionization X-ray Warm Absorber– X-ray eclipsing clouds– Cometary tails on X-ray eclipsing clouds
• Forms naturally• Appealing: Disk winds still solve everything
KWWL.com