Impact of Jet Feedback on H2 and Star

Formation in Radio Galaxies

Patrick Ogle (Caltech, Spitzer Science Center)

R. Antonucci, C. Leipski, Phil Appleton, Francois Boulanger

Normal Star-Forming Galaxies•Spitzer SINGS survey of nearbygalaxies (Smith 07).

•Polycyclic Aromatic Hydrocarbon (PAH) dust is excited by UV in stellar photodissociation regions.

•PAH emission is useful for estimating star-formation rates in AGN hosts. The 7.7 um feature is not excited by AGN activity.

•H2 emission is weak.PAHs

H2

Radio Galaxies with Extreme H2 Spitzer IRS radio galaxy survey:17/57 (30%) of 3C radio galaxies at z<0.2 have strong H2!

Environment:• 14/17 have close or interactingcompanions.

• 6/17 live in cool-core clusters.

(Ogle et al. 08, in prep.)

Radio Galaxy 3C 326 (z=0.089)

●Spitzer IRS spectrum dominated by pure-rotational H2 lines: ●L(H2)=81041 erg/s●L(H2)/LIR~0.05-0.1 ●M(H2)=1.1109 M

(Ogle et al. 2007)

Spitzer IRAC: galaxy pair (sep. 42 kpc), connected by tidal bridge.

WSRT 21cm

1.9 Mpc radio lobes (Leahy).

H2 Shock-Excitation in 3C 326

●H2 Emission dominates coolingin C-type shocks (Le Bourlot 02)

•T(H2)=150-1000 K●Magnetic (C-type) shock model:2 velocities: v=4, 20 km/s●nH=104 cm-3, B=100 G(Guillard 08, in prep)

MOHEGs = H2 Emission Galaxies

●Stephan's Quintet shock (Appleton et al. 06). ●Zw 3146 cool-core cluster cD (Egami et al. 06).

●SINGS AGNs(Roussel et al. 07) ●Radio Galaxies (Ogle et al. 07,08)

L(H2)/L(IR)>210-3

Infrared Luminosity

Shocks vs. Star Formation

●H2 and PAH dust occupy same ISM phase.

●Star forming galaxies have L(H2)/L(7.7 m PAH)~810-3

●Larger H2/PAH indicates shock heated H2 in: -Radio galaxies (Ogle 08)-LINERs, Seyferts (Roussel 07)-Dusty ellipticals (Kaneda 08).

(Ogle et al. 2008)

Infrared Luminosity

Shocks vs. AGN X-ray Heating

●AGN X-ray luminosities from Chandra (Evans 06; Hardcastle 06; Balmaverde 06; Ho 01)

● XDR maximum theoretical X-ray to H2 conversion ~ 5% (Maloney 1996)

●Most of the AGN are not strong enough X-ray emitters to power the H2.

AGN X-ray Luminosity

Radio Jet Mechanical Heating?

● Radio jet cavity powers are measured for 6/17 MOHEGs.(Rafferty 06; Bîrzan 04)

● P(jet cavity) = 4pV/t(bouyant) p,V, t estimated via Chandra.

•L(H2)/P(jet)=10-4 -- 210-3

•Jet-driven H2 outflow or fountain? (FWHM ~ 500 km/s seen in some sources.)

•H2 cooling time ~104 yr. --Requires sustained heating

Radio Jet Cavity Power

Perseus A-- Multiphase ISMCO (2-1) H

•M(cold H2)=41010 M from CO (2-1) (Salome 06)

•M(4.0,0.6 keV)~(1011,109 M)

(Chandra, Fabian 06)

•M(warm H2)>7107 M(Johnstone 07)

•M(H II)= 3107 M(Conselice 01)

H2

3C 293 Jet-Induced Outflow

• 1000 km/s H I and [O II] outflows (Morganti 03; Emonts 05).

•Possible jet/CO interaction.•M(H2 cold)=1.51010 M

(A. Evans et al. 1999)

•M(H2 warm)=1109 M

(Ogle 2008)

M(HI)=20 M/yr M(HI)=107 M

Mion=0.1 M/yr

.

.

Rogues Gallery3C 31

3C 338

3C 315

3C

3C 433

3C 4363C 326

3C 310

3C 386

Credit: DRAGN Atlas

Star Formation Rates

●MOHEG star formation rates are modest: 0.01-3 M/yr (from PAH inside 3.7” slit)

Will add little to ~ 1011 M

stellar bulge in a Hubble time. ●SFR does not correlate with warm H2 mass.

●H2 depletion timescales:3107--71010 yr

Ogle et al. 2008

Star Formation Efficiency

• 3C 326 and 293 fall belowSchmidt law for star formation in normal galaxies.

• 3C 326 SFR~0.1M/yr at R<3.1 kpc.

Our PdB CO observations indicate (H2)>350 M/pc2

• Jets may suppress disk formation by driving H2 outflows or fountains with large velocity dispersion and low volume filling factors.

Kennicutt 1998

PdB

?

326

293

Future Directions

●Spitzer IRS spectra of more radio galaxies with H I outflows.●Spitzer spectra of compact (CSS/GPS) radio sources●Spitzer spectral map of MRC 1138 (z=2) radio galaxy.

●VLT/SINFONI IFU spectral maps of near-IR rovibrational H2 ●CO maps and cold H2 masses, ’s with PdB interferometer. ALSO NEEDED:●More AGN X-ray fluxes (Chandra)●Jet power estimates for non-cavity radio sources.

●THEORY! How do jets gently heat 1109 M of H2 to 200 K??

COMING SOON: