The Evolutionary Connection Between SMGs & AGN as Probed by - PowerPoint PPT Presentation

The Evolutionary Connection Between SMGs & AGN as Probed by Molecular Gas Excitation Chelsea E. Sharon Herschel Postdoctoral Fellow McMaster University Sharon et al. 2016, ApJ, 827, 18 Collaborators: Dominik Riechers, Jackie Hodge, Chris Carilli, Fabian Walter, Axel Weiss, Kirsten Knudsen, & Jeff Wagg

Reminder: Theoretical Motivation for AGN Feedback Dark matter * baryon fraction –5 Weller et al. (2005) Bell et al. (2003) SN D a r k m a t t e –1 ) r –10 log 10 N (Mpc –3 M –15 AGNs Read & Trentham (2005): Elliptical galaxies –20 All galaxies 6 8 10 12 14 log 10 ( M /M ) Kormendy & Ho 2013 ARA&A

Reminder: 2 AGN Feedback Modes • Kinetic/jet/radio/maintenance mode Perseus Cluster • Definitely important in (Chandra/X-ray) most massive galaxies • Effects on hot halo gas are observed • Radiative/wind mode • Outflows are ubiquitous • Mostly observed in ionized and atomic phases • Difficult to distinguish between AGN-driven and starburst-driven winds Rubin et al. 2013

AGN Feedback & Molecular Gas If AGN quench star 0.03 0.3 formation, we should see 0.02 0.2 signs in the molecular gas 0.01 0.1 0 0 • Recent work clearly -1000 -500 0 500 1000 -1000 -500 0 500 1000 Velocity [Km/s] Velocity [Km/s] identifies molecular gas Feruglio et al. 2010 outflows in nearby AGN- host galaxies • Some low-z AGN have ultra-high excitation molecular lines • But similar observations are challenging at peak epoch of galaxy assembly Cicone et al. 2014 (see also Fiore et al. 2017)

AGN Feedback & Molecular Gas If AGN quench star 0.03 0.3 formation, we should see 0.02 0.2 signs in the molecular gas 0.01 0.1 0 0 • Recent work clearly -1000 -500 0 500 1000 -1000 -500 0 500 1000 Velocity [Km/s] Velocity [Km/s] identifies molecular gas Feruglio et al. 2010 outflows in nearby AGN- 40 host galaxies i n t e r f e r o m e t r i c J C M T e x t F T S m a p • Some low-z AGN have F T S d ee p li n e f l u x [ 10 - 17 W m - 2 ] 30 P A C S ultra-high excitation 20 molecular lines • But similar observations 10 are challenging at peak 0 epoch of galaxy assembly 0 5 10 15 20 J u p Spinoglio et al. 2012 (see also Rosenberg et al. 2015)

A Promising Connection? Low-J CO Excitation • Based on radiative transfer modeling, r 3,1 is a good indicator of the molecular gas physical conditions r # Phases r 3,1 At high-z: AGN host galaxies 5 Single phase, r 3,1 =1 r 3,1 =1 thermalized (Riechers et al. 2011) Submillimeter galaxies (SMGs) r 3,1 =0.6 8 Multi-phase r 3,1 <1 (e.g., Swinbank et al. 2010; Harris et al. 2010; Ivison et al. 2011; Riechers et al. 2011)

RXJ0911+0551 (QL) 58″ 5 spectrally New(-ish) Survey: z=2.796 DEC (J2000) +05° 50′ resolved 56″ Total Molecular Gas Census 54″ 52″ CO(1−0) − 1 Δv int =200 km s in z~2 SMGs & AGN − 1 beam − 1 50″ σ =0.008 Jy km s 27.8 s 27.7 s 27.6 s 27.5 s 27.4 s 27.3 s h 11 m RA (J2000) 09 HS1002+4400 (Q) z=2.101 DEC (J2000) +43° 45′ detections 15″ 3 >5 σ • VLA CO(1–0) observations of all 10″ z~2 SMGs & AGN with existing CO(1−0) 5″ − 1 Δv int =1200 km s CO(3–2) detections − 1 beam − 1 σ =0.055 Jy km s 0″ 18.0 s 17.8 s 17.6 s 17.4 s 17.2 s 17.0 s h 05 m RA (J2000) 10 • Goal: 5–7 σ detections for each J22174+0015 (S) z=3.099 45″ DEC (J2000) +00° 15′ detections 5 3–5 σ (although not the case in practice) 40″ 35″ • 13 new detections + 1 limit CO(1−0) − 1 Δv int =1200 km s − 1 beam − 1 30″ σ =0.020 Jy km s 35.8 s 35.6 s 35.4 s 35.2 s 35.0 s 34.8 s • +15 literature sources h 17 m RA (J2000) 22 MG0414+0534 (QL) 50″ 1 upper limit z=2.639 DEC (J2000) +05° 34′ ➡ 15 SMGs (10 lensed/5 unlensed) 45″ 40″ CO(1−0) ➡ 14 AGN (9 lensed/5 unlensed) − 1 v int =580 km s 35″ − 1 beam − 1 σ =0.020 Jy km s 38.4 s 38.2 s 38.0 s 37.8 s 37.6 s 37.4 s h 14 m RA (J2000) 04

Is there a difference? No! 8 Old Distribution 1.0 AGN SMGs Cumulative Fraction 6 0.8 0.6 N 4 0.4 2 0.2 AGN SMGs 0 0.0 0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.5 1.0 1.5 2.0 2.5 r 3,1 r 3,1 8 New Distribution 1.0 AGN SMGs Cumulative Fraction 6 0.8 0.6 N 4 0.4 2 0.2 AGN SMGs 0 0.0 0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.5 1.0 1.5 2.0 2.5 r 3,1 r 3,1

What about the line FWHMs? No! 6 5 CO(1−0) SMGs 5 CO(3−2) AGN 4 4 3 N N 3 2 FWHM Ratios 2 1 FWHMs 1 0 0 0 200 400 600 800 1000 0.6 0.8 1.0 1.2 1.4 FWHM (km s –1 ) FWHM 3–2 /FWHM 1–0 1.0 1.0 CO(1−0) SMGs CO(3−2) AGN 0.8 0.8 Cumulative Fraction Cumulative Fraction 0.6 0.6 0.4 0.4 0.2 0.2 0.0 0.0 0 200 400 600 800 1000 0.6 0.8 1.0 1.2 1.4 FWHM (km s –1 ) FWHM 3–2 /FWHM 1–0

Why did the difference disappear? • It’s easy to excite CO(3–2) in dense star forming regions • Issues with AGN/star formation content: • AGN are largely literature sources (as per initial r 3,1 detections) and not selected in a physically motivated way • These AGN have star formation (IR bright), and relative strength of the AGN (compared to SF) is not quantified • Original samples were well-characterized sources, clear on AGN content, and expanded samples are less clear • Some galaxies may be mis-classified, or their central AGN is deeply buried in dust • Differential lensing may affect the observed excitation conditions

What else can we do? • Correlation hunting between r 3,1 and other parameters doesn’t turn up anything interesting • Do see correlation between r 3,1 and star formation efficiency, as previously found at low z • No significant excitation dependence in integrated Schmidt-kennicutt relation, as found at low z 2.5 14 AGN, unlensed FLS 3 (z=6.34) AGN, lensed SMG, unlensed 2.0 13 SMG, lensed local U/LIRGs (P12+G14) local IR-bright galaxies (Y03) other 12 CO(3–2) CO(1–0) 1.5 log(L FIR /L ) Cosmic Eye r 3,1 cB58 11 1.0 AGN, unlensed 10 AGN, lensed SMG, unlensed 0.5 N=1 for high-z and/or U/LIRGs SMG, lensed N=1.2 for low-z IR-bright (Y03) local U/LIRGs (P12+G14) 9 local IR-bright galaxies (Y03) 0.0 0 100 200 300 400 500 7 8 9 10 11 12 L FIR /Lʹ CO (L (K km s –1 pc 2 ) –1 ) log(Lʹ CO /(K km s –1 pc 2 ))

What’s next? • Argument still holds: If AGN feedback is directly affecting star-forming gas, we should see signs of that in the gas physical conditions. • Need a way to disentangle the relative strength of AGN’ and star formation’s effects on the ISM. → Survey of gas excitation in unlensed systems where we have good (mid-) IR diagnostics of the AGN strength. Kirkpatrick et al. 2015

New Survey: Multi-J CO in High-z Galaxies with IRS spectra • Started survey at the VLA and got CO(1–0) for 11 of 12 sources so far (6 completed, above) • Note: these only had IRS redshifts prior to CO(1–0) • NOEMA observations of higher-J lines in a sub-sample have just completed…

Summary/Concluding Thoughts • No systematic difference in CO(3–2)/CO(1–0) line ratios in SMGs and IR-bright AGN host galaxies • No difference in CO(1–0) and CO(3–2) line FWHMs • No new trends in CO(3–2)/CO(1–0) with other galaxy properties (reproduces low-z correlation with SFE) • Lack of difference largely because high SFRs can easily excite high CO(3–2)/CO(1–0) ratios and IR-bright AGN also have high SFRs • Samples w/ better handle on AGN strength at long wavelengths will give us a better sense of AGN-SF connection and are in progress Open Question: What role, if any, do AGN play in the evolution of dusty starbursts like SMGs?