M87 interaction between a SMBH and gas rich atmosphereShocks, Buoyant plasma bubbles, Jet, Cavities, Filaments
Outbursts from Supermassive Black Holes Forman, Churazov, Jones, Bohringer, Begelman, Owen,
Eilek, Nulsen, Vihlinin, Markevitch, Heinz, Kraft
Unambiguous signature of an AGN triggered shockOutburst energyOutburst durationEnergy channels for heating
Cool X-ray filamentary structureClear evidence for bubbles
•Outbursts from galaxies to (M87 to) rich clusters
•Outbursts range from 1055 < ∆E < 1062 ergs
•See growth of SMBHs - ∆MSMBH ∝ ∆ EOUTBURST / c2
•∆MSMBH up to 3x108 solar masses per outburst
2
Hot X-ray emitting atmospheres - “fossil record” of SMBM activity •Observe outburst frequency •Measure total power - mechanical vs. radiative (cavities)•Understand interaction of outburst with surroundings•Insight into high redshift, early universe •Growth/formation of galaxies•Growth of SMBH
SMBH and Parent Galaxy
Mbulge-M
M -
Magorrian et al.Gebhart et al.Ferrarese & Merritt
M
MVelocity Dispersion
MBulge
3
Millenium Run + Semi-analytic Galaxy Evolution
•1010 particles of 109 Msun
• extract merger trees of dark matter halos from z=20 to z=0
•z=0 dark matter •z=0 light
Croton et al. 2006
Croton et al. 2006“The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies”
4
Millenium Run + Semi-analytic Galaxy EvolutionCroton et al. 2006
For massive galaxies/halos, AGN feedback into hot coronae is long-lived phase
Study this long-lived phase of outbursts and feedback into the hot coronae
Rapid Cooling
Hot Halo
Massive halos/galaxies •Form hot gas coronae at early times•Growth/merging continues with little star formation•Oldest systems become “red and dead” - but still growing via mergers•AGN heating is key•Downsizing - more massive galaxies end star formation at higher z; appears “anti-hierarchical”
5
Setting the stage Family of increasing mass, temperature, and luminosity
E/S0 Galaxies Groups Clusters
Lx (ergs/sec) 1040-42 1042-43 1043-46
Gas Temp 0.5-1.0 keV 1-3 keV 2-15 keV
Mgas/Mstellar 0.02 1 5
6
Hot gas seen ONLY in X-ray band - thermal bremsstrahlung + lines
•Gas provides a fossil record of mass ejections and energy outbursts•For clusters, 16% of mass is luminous baryons (mostly hot gas)
•Measure heavy element enrichment - history of star formation
•See reflections of energy outbursts in cavities over cosmic times
Setting the stage Family of increasing mass, temperature, and luminosity
7
Cooling Flows
• Cowie & Binney (1977) Fabian & Nulsen (1977) “Cooling gas in the cores of clusters can accrete at significant rates onto slow-moving central galaxies”
• Strong surface brightness peak dense gas short cooling time
• Hot gas radiates – gas must cool unless reheated, then compressed by ICM
• Mass Deposition rates are large (100 -1000 M/yr) - more than 50%
• But large amounts of cool gas were not detected
• Emission lines from cooling gas NOT SEEN byXMM-NEWTON OGS (cool gas only 10% of prediction) (e.g., Peterson et al. 2001, 2002; Peterson & Fabian 2005)
Allen/Fabian
Virgo Cluster - X-ray/Optical
1’=4.65 kpc; 2o=0.5 Mpc Central galaxy in Virgo cluster D=16 Mpc
•3x109Msun supermassive black hole•Spectacular jet (e.g. Marshall et al.)•Nearby (16 Mpc; 1’=4.5 kpc, 1”=75 pc)•Classic cooling flow (24 Msun/yr)•Ideal system to study SMBH/gas interaction
Chandra-XMM-VLA View• Two X-ray “arms”
• X-ray (thermal gas) and radio (relativistic plasma) “related”
• Eastern arm - classical buoyant bubble with torus (Churazov et al 2001) – XMM-Newton shows cool arms of uplifted gas (Belsole
et al 2001; Molendi 2002)
• Southwestern arm - less direct relationship - radio envelops gas
M87
Density and Pressure Maps
Central Piston Shock Filamentary arms
Gas Pressure (3.5-7.5 keV)
Gas Density (1.2-2.5keV)
Central Region of M87 - the driving force
• Nucleus, jet (knots)• Cavities surrounding the jet and the (unseen)
counterjet• Bubble breaking from counter jet cavity
– Perpendicular to jet axis; – Radius ~1kpc. – Formation time ~4 x106 years
• Piston driving shock• X-ray rim is low entropy gas
uplifted/displaced by relativistic plasma
6 cm
6cm VLA
SMBH 3x109Msun
Shock Model I - the dataHard (3.5-7.5 keV) pressure soft (1.2-2.5 keV) density profiles
Projected Deprojected
Consistent density and temperature jumps
T2/T1= 1.19
M~1.2yield same Mach number: (MT=1.20 Μρ.24)
Rankine-Hugoniot Shock Jump Conditions
€
ρ2 /ρ1 =γ +1( )M 2
γ +1( ) + γ −1( ) M 2 −1( )
€
ρ2 /ρ1 =1.34
€
T2 /T1 =γ +1( ) + 2γ M 2 −1( )[ ] γ +1( ) + γ −1( ) M 2 −1( )[ ]
γ +1( )2M 2
Outburst Energy
Series of models with varying initial outburst energy2, 5, 10, 20 x 1057 ergs
Match to dataE = 5 x 10 57 ergsDetermined by jumps
Fast - large shock heated region
Absence sets outburst duration 2-5 million yrs
Slow - cool rim
Shock-heated gas if τoutburst is too short Absence of hot region limits duration of outburst
Must be longer than 2 million years
Derive outburst timescale
19
Fast/Slow Cartoon
Fast
Fast SlowRadio Lobes
Radio bright
X-ray dim
Small Large
Shock heated gas
Radio dim
X-ray dim
Yes No
Cool rims No Yes
Rarefaction region Yes Yes
Outer shock Yes Yes
Slow
RadioLobes
RadioLobes
Hot, dim
Cool, bright
20
Where does the energy go ?
Sedov Slow (2-5 Myr)Slow (2-5 Myr)
Kinetic energy in the shock
~6x1056 ergs
(11%)
~6x1056 ergs
(11%)
Will be carried away
~12x1056 ergs (22%)
~12x1056 ergs
(22%)
Enthalpy of the central bubble
~1.7x1056 ergs (3.4%)
~2.3-3.7x1057
ergs (46%-64%)
Heating 100-22=78% >100-22=78%
(eventually)
Sequence of buoyant bubbles Many small bubbles (comparable to “bud”)
Effervecent heating - Begelman•PV ~ 1054 - 1055 ergs τrise ~ 107 yearsArms - resolved
Eastern arm - classical buoyant bubbleSouthwestern arm - overpressured and “fine” (~100pc, like bubble rims) - limit bulk gas velocities in core
4.65 kpc
90 cm (Owen et al.)
1.2-2.5 keV
M87
Soft Filamentary Web
22
Organized and Disorganized
4.65 kpc
Ruszkowski/BegelmanSimulation for Perseus
Both large scale bubblesAND
Small scale chaotic bubbles
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Radio (blue) Chandra X-ray (red)
M87 shocks and bubbles contribute to heatingBoth naturally arise from AGN outburstsShock carries away ≤ 20-25% of energy75% of outburst available to heat (eventually)
Filaments Cool thermal rims of bubbles Southwestern arm - interaction with radio plasmaShock (and trailing rarefaction region) R, jump in T or ρ => Total deposited energy 5x1057 erg Lobes and shock radius => Age ≈ 14x106 yrCool/bright rims => “slow” energy deposition 2-5x106 yearsAverage energy release: few x 1043 erg/s ≈ Cooling losses Dunn et al. - 55 cluster sample, 20 have τ<3x109 yrs and 75% show bubblesRafferty - 33 clusters; 50% withbubbles and sufficient energy to quench cooling
Pre-Einstein early type galaxies •Gas free - Stellar mass loss removed by SN driven winds.
Einstein Observatory images showed extended, hot coronae:•~1 keV temperatures; masses to 1010 M , •Strong correlation of LX and LB but much scatter.
(e.g. Forman et al. 1979, 1985, Canizares et al. 1987)•High central gas densities => short cooling times •Accretion rates of 0.02-3 Msun/year (Nulsen et al. 1984, Thomas et al. 1986 )
Hot Gas in Early-type Galaxies - The Einstein Era
A Chandra survey of ~160 early type galaxies to measure outburst energy, age, frequency, plus diffuse/gas luminosity
and nuclear emission (Jones et al.)
Study hot gas - as a function M, velocity dispersion, ….Measure cavities - determine outburst energies (PV) and timescalesDerive nuclear luminosities - correlate with gas density
In luminous ellipticals, most of the X-ray emission is from hot gas, In fainter systems, emission from LMXBs makes nearly all of the
“diffuse” emission
Gas dominates “diffuse” emission
Correlation of Lx with L
and Land
Mostly unresolved LMXB’s (hard specta)
Galaxies with little hot ISM
Exploding Elliptical -NGC4636
•Strange X-ray structure in an otherwise normal Virgo elliptical galaxy•Double pin wheel-like structure in X-rays! X-ray arms ~8 kpc long.•Nuclear outburst 3 x 106 years ago with energy 6 x 1056 ergs•But small weak radio source
Jones et al 2001
29
Bubbles in a galaxy -- M84
For Perseus, M87, M84, and for almost all others
Gas surrounding bubble is cool
Usually no shock heating in lobe H-shaped gas has
kT~ 0.6 keV
Ambient gas temperature increases from 0.6 to 0.8 keV with increasing radius
.
Lobes ~ 4 kpc diameter
outburst ~ 4 - 6 x 106 yrs ago
Interaction with radio lobes of 3C272.1
Tail to south & northern lobe compression
motion of M84 to the north
X-ray Radio
Galaxy rims are (generally) cool (like cluster) - no shocksBubbles (seen as cavities) gently uplift and impart energy to the gas
NGC4636
3 106 years
2 106 years5 106 years
107 years
NGC5846
5 106 years
3 106 years
5 107 years
NGC507
Galaxies with diffuse gas
How Common are AGN Outbursts in Galaxies?Determine fraction of Galaxies with Cavities
Galaxies with cavities
In luminous ellipticals (including some poor groups), 30% have cavities
In galaxies, outbursts are recent (=> frequent) and
impart significant energy to the ISM
AGE of outbursts
Ages and outburst energy for the 27 systems with cavities
PV (ergs)1053 1055 1057 1059
•X-ray emission detected from the nucleus for ~80% of early-type galaxies
Nuclear activity - “AGN”Determine fraction with nuclear X-ray emission
In “normal” early-typegalaxies
ConclusionsEnergy input from AGN is common in galaxies- reheats cooling gas, drives gas from their halos,
and is important for galaxy evolution
In luminous ellipticals, ~30% have cavities => recent outbursts
- typical ages are 3x106 to 6x107 years
- typical outburst energies (estimated from cavity sizes) are 1055 - 1058 ergs
~80% of all early type galaxies have weak X-ray “AGN”
35
Hydra A (Nulsen et al 2005)
Small cavities in core, medium cavities and a shock Shock front 200-300 kpc from AGN
Shock energy 1061 ergs -- 1.4 X 108 years since outburst
Hydra A (Nulsen et al 2005)
Chandra radio contours on X-ray
Small cavities in core , medium cavities and a shock Shock front 200-300 kpc from AGN
Shock energy 1061 ergs -- 1.4 X 108 years since outburst
Cluster Scale Outbursts MSO735.6+7421 6 X 1061 ergs driving shock
(McNamara et al 2005)
Cluster Lx = 1045 ergs/sec z=0.22X-ray bright region - edge of radio cocoon lies at location of shockRadio lobes fill cavities (200 kpc diam) - displace and compress X-ray gas Work to inflate each cavity ~1061 ergs; age of shock 1 X 108 years Average power 1.7 X 1046 ergs/sec
Growth of SMBH by accretion in “old” stellar population systems(Rafferty et al. 2006 - solar mass/yr) with star formation to maintain MBH-Mbulge relation
Mechanical power balances cooling in 50% of clusters AGN outbursts deposit energy into gas through shocks and bubbles
Outbursts from Clusters to GalaxiesSOURCE SHOCK
RADIUS(kpc)
ENERGY
(1061 erg)
AGE
(My)
MEAN POWER
(1046 erg/s)
∆M
(108 Msun)
MS0735.6Hercules A
Hydra AM87
NGC4636
230160210145
5.73
0.90.0005
0.00006
10459
136143
1.71.60.2
0.00120.0007
31.70.5
0.00030.00003
€
˙ M BH ≈ 0.1−1
Impact of AGN outbursts on hot gas
•M87 outburst τ~14x106 years, τ~2-5x106 years; inflates inner region “classical shock - seen in density/temperature & rarefaction region slow expansion of “piston” (no large shock heated region)
Outburst energy matches cooling • M87 arms from buoyant bubbles; soft filamentary web; complex (magnetic field) interactions of radio plasma bubbles with ISM•Galaxy outbursts and mini AGN are common (see talk by Christine Jones) •Outbursts from galaxies to clusters 1055-1062 ergs which grow SMBH
NGC4636M87Hydra A
Impact of AGN outbursts on hot gas
NGC4636M87Hydra A
•Reheat cooling gas through shocks/buoyant bubbles in all gas rich systems i.e. those with bulges and black holes•Critical to galaxy evolution/downsizing models
•Massive galaxies are “red and dead”•Evolution continues but not (appreciable) star formation
•Hot coronae “contain” AGN feedback energy over cosmological times•X-ray observations allow study of the outbursts and exactly how energy is injected into the hot surrounding atmosphere•Critical to understanding the new view of galaxy and black hole evolution