The central few parsec region of AGN in the IR M. Almudena Prieto (IAC) Crete, June 2008

PARSEC program High spatial resolution study of the Nearest Active Galactic Nuclei in the Southern Hemisphere From UV to optical (HST) to IR (adaptive optics ) to radio (VLA / ATCA) What is new: Achieved angular scales VLT /AO 1 - 5 µm  θ < 0.1” ( ~ 1- 20 pc) VLT 10 - 20 µm  θ < 0.4” For some of the brightest: Interferometry at 10 µm  θ ~ 0.03“ ( ~ 0.5 pc) What we had: HST at 0.3 - 0.9 µm  θ < 0.1” VLA/VLBA and ATCA  θ < 0.1”

Some of the nearest … 1”/pc L(20-100 keV) FWHMcore 2 µm S2/RG CenA 16 3 - 5x1042 < 1 pc S2 Circinus 19 2x1042 ~ 2 pc S1/Li N1097 70 5x1040* < 10 pc S2 N1068 70 2x1042 ~1x2pc (10um) S2 N1386 94 1042* < 8 pc S1 N1566 96 4x1042 < 11 pc S2 N7582 150 9x1042 < 12 pc S2 ESO428-014 158 6x1042* < 20 pc S1.9 N5506 180 1043 < 10 pc S1 N3783 280 5x1043 < 22 pc S1 N7469 470 6x1043 < 38 pc Qso 3C 273 4600 1-4x1047 < 300 pc

Some AGN dominate the galaxy light regardless of the aperture size AGN in the IR 3C 273 NGC 5506 Sy 1.9 2MASS Some AGN dominate the galaxy light regardless of the aperture size

AGN in the IR NGC 1068 Centaurus A NGC 1566 Circinus 2MASS In others, the galaxy dominates IR light by at least an order of magnitude

Modest AGN: their IR luminosity is a few percent of the total IR output RG / S2 S2 S1 S2

Dominating AGN: their IR luminosity is ~100% of the total QSO S1 S2 3c273 from Lichti,… Courvoisier et al. 1995 except radio which is taken from VLBI from different authors and IR

VLT / VISIR 10 - 20 um images down to 0.4 arcsec resolution  excess IRAS flux has to come from diffuse extended emission NGC1068 - Q Galliano et al. 2006 Cen A : also found unresolved by Radomski et al 2008 (8.8 and 18.3um gemini South). In Gemini 18,3 um (filter is 1.5um width vs 0.37um in our case w. visir), a blob is seen next to the nucleus N-E In the jet direction, which is coinciding with a blob in Palpha emission (HST, Marconi) Reunanen et al. 2008

…… but in other AGN: excess IRAS flux comes from circumnuclear star forming regions Liner / S1 S1 S2 NGC 1097 - Q Reunanen et al. 2008

The true energy output in the IR LIRcore IR(large-ap/core) X>20kev / IRcore S1/Li N1097 6.5x1041 700 80% S2/RG CenA 2x1042 50 1 - 3 S2 Circinus 6x1042 10 30% S1 N1566 2x1042 200 2 S2 N7582 2.5x1043  20 40% S2 N1068 8.5x1043 20 20% S1.9 N5506 2x1044 1 20% S1 N3783 4x1044 1 10% Qso 3C 273 9x1046 1 1 - 4

Summary AGN selection by IRAS colors has been very successful. This is surprising considering that: IRAS luminosity overestimates the core luminosity by factors > 10 SEDs from large IR apertures differ dramatically from those derived at high spatial resolution Large aperture IR excess found associated with starformation or low surface brightness emission ==> Acknowledging the IRAS success, it all looks as if galaxies would know a priori whether an AGN is being nursed at their core