Franoise Combes March 25, 2015 Gas Flows in Galactic Nuclei 1 Perseus cooling flow Mrk 231 NGC 4258 NGC 1433 Outflows more visible than inflow 2 Outflows are violent events (~1Myr) Inflow is a slow process (~1Gyr) Cosmic filament size~50kpc Larger than a galaxy, diffuse gas Settles down in the disk in rotation Secular evolution, slow infall in the disk Ceverino et al Agertz et al 2011 Except fountain effect, HVC.. Companions, gas bridges Necessity of outflows for quenching 3 Baugh 2006, Eke et al 2006, Jenkins et al 2001 Star formation SN, stellar winds AGN feedback Radio jets 4 Madau & Dickinson 2014BHAR x3300 X-ray IR SFR Star formation history Outline 5 1- AGN feedback, quenched red nuggets 2- SN+AGN molecular outflows in galaxies 3- Mechanisms -- Energetics M BH = M gal E gal ~M gal 2 E BH ~0.1M BH c 2 E BH /E gal > 80 AGN Pounds & King 2013 AGN energy is largely enough 1- Two main modes for AGN feedback 6 Quasar mode: radiative or winds When luminosity close to Eddington, young QSO, high z L Edd = 4 GM BH m p c/ T M BH ~f T 4, f gas fraction Same consideration with radiation pressure on dust, with d d / T ~1000, limitation of Mbulge to 1000 M BH ? Radio mode, or kinetic mode, jets When L < 0.01 L edd, low z, Massive galaxies, Radio E-gal Not destructive: keeps a balance cooling-heating Radiatively inefficient flow ADAF High frequency of cooling flows in clusters, Low-luminosity AGN Seyferts.. Radiative mode in simulations 7 Springel et al. ( ), Hopkins et al SFR ~ n with n=1, 1.5, 2 SN feedback+ BH growth and associated feedback Sub-grid physics How much feedback? Gabor & Bournaud 2014: No quenching effect Compact red and blue galaxies 8 Barro et al 2013 CANDELS M > Mo Black lines: density of cSFG required to explain the red nugget t burst =0.3-1 Gyr Possible scenarios 9 Barro et al 2013 Two evolutionary tracks of QG formation: (1) early (z>2), formation path of rapidly quenched cSFGs fading into cQGs that later enlarge, (2) late-arrival (z> L AGN /c // Adiabatic phase, or Sedov-Taylor phase in SN remnant Slow cooling --High momentum fluxes 18 Faucher-Gigure & Quataert 2012 a b c Costa, Sijacki, Haehnelt, 2014 Tombesi 10, 14 UFO v/c Impact of a fast wind (UFO) on the ISM 19 King & Pounds 2015 Two phases 1- Starting with M BH below the M- relation, the v=0.1c wind is stopped by an ISM shock 1kpc, the flow becomes energy-driven The pressure is >> v 2, the ISM is easily ejected, with Vesc (seen in molecular outflows) Regulation of M bulge A disk is a too massive obstacle, the jet is diverted bipolar Several modes simulated 20 Quasar mode, when dM BH /dt > 0.01 Edd Energy released spherically Radio-jets otherwise: V= 10 4 km/s, in a cylinder perp. to the disk Energy-driven, much more efficient than momentum-driven AGN outflows with > 10 Ledd/c Entrained cold gas > 10 9 Mo If after-shock cooling with metals Costa et al 2014 Comparison between realistic cosmological simulations and idealised ones in spherically gravitational potentiels A factor 10 larger momentum flow is required for AGN feedback to be efficient Quasar mode:Two-phase simulations 21 Nayakshin 2014 Most of the outflow kinetic energy escapes through the voids Positive and negative feedback Cold gas is pushed by ram-pressure More feedback on low-density gas Could lead to M- relation AGN wind feedback fails 22 AGN could trigger a starburst by compressing the gas Gaibler et al 2012 May be AGN positive feedback SF feedback? Starburst in a ring AGN-triggered star formation 23 The AGN provides an extra-pressure forming more clumps in the molecular gas Bieri et al 2015 Radio mode: Fractal structure 2pc-1kpc 24 Efficient relativistic jets; Influence of the porosity Wagner & Bicknell 2011 Jet in the disk plane 25 NGC 4258 Cecil et al 2000 Positive AGN feedback Radio jets triggered SF 26 Young, restarted radio loud AGN 4C12.50 The outflow is located 100 pc from the nucleus where the radio jet interacts with the ISM Morganti et al 2013, Dasyra & Combes 2012 Silk 2005, Dubois et al 2013 Feedback in low-luminosity AGN 27 NGC 1433: barred spiral, CO(3-2) with ALMA Molecular gas fueling the AGN, + outflow // the minor axis L kin =0.5 dM/dt v 2 ~ erg/s L bol (AGN)= erg/s Flow momentum > 10 L AGN /c Combes et al 2013 M H2 = M o in FOV=18 100km/s flow 7% of the mass= Mo Smallest flow detected SUMMARY: AGN outflows 28 Mechanisms: Quasar modes (winds), powerful AGN Or Radio modes (jets), for low-luminosity AGN, lower z Molecular outflows are now observed frequently, around AGN, v= km/s Mo, load factors 1-5 Energy-conserving flow: Momentum boost 20 L AGN /c However, not efficient to quench SF (or even trigger SF?) AGN radio mode is very efficient in Cool Core clusters to moderate the cooling: mechanical with radio jets, cold gas accretion