1. Isabella Prandoni (INAF-IRA, Italy) INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 A view of the sub-mJy radio population: The AGN component LOFAR perspectives

2. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 2. Classical RL-AGNs  steep/flat or FRI/FRII Mainly steep FRI RGs [logP <24] I – Modeling the sub-mJy population 3. RQ-AGN 3. RQ-AGN (Jarvis & Rawlings 04) RS  compact & steep (<<10 kpc) 22 < logP <24 em. line spectrum  Type 1/Type 2 1. SF galaxies EMERGENCE OF NEW POPULATION(S) EXCESS @ S<1 mJy: To qualitatively reproduce counts:

3. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 Radio Power Distribution Radio Power Distribution: (DEEP1abc) ETS  10 23-25 W Hz -1 Low-intermediate power AGNs QSO  P < 10 25-26 WHz -1 RI-QSOs [RQ-QSOs: 22<logP<24] LTS  2/3 P < 10 24 W Hz -1 Star-forming gals 64 % 14 % 19 % (Mignano,IP+ 08)  Sample largely dominated (78%) by AGN activity  AGNs: mostly FRI-like (No evidence of RQ-AGNs) II – Obs. properties of sub-mJy sources ATESP-DEEP1 Sample:115 RS with S>0.4 mJy in 1 sq. degr.

4. AGN AGN LTS/SB LTS/SB ETS ETS INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 In DEEP1abc: 24/39 ETS are flat/inverted: - P 5 GHz ~ 10 22-24 W Hz -1 (+ ETS spectra) - Typically compact (<10-20 kpc) (+ flat)  ADAF - ADAF+jet systems? (local LLAGNs) eg. Falcke & Biermann 99 Upper limits Double/Extended RS (Mignano, IP+ 08) II – Flat spectrum ETS FRI larger & steep core-dominated FRI? [base-jet emission] flat steep flat steep  Multi-freq. (0.1 –100 GHz) high-res. radio obs. needed

5. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 Prandoni, Ricci+ in prep Flux-limited sub-set of 15 ATESP-DEEP1 ETS with S>0.6 mJy ATCA: Simultaneous Multi- freq. obs. [5, 8, 20 GHz] (14 in 2008 to be added) most RS consistent with jet dominated systems ( α<0.2) Base jet components or Jet+ADAF ( α>=0) systems 2 RS still consistent with pure ADAF systems ( α>0.2 ) [1.4 - 5 GHz] [8 - 20 GHz] II – ETS: High frequency follow-up pure ADAF candidates α high <0.2 Jet-dominatedsystems Jet+ADAF

6. II – Radio-quiet AGNs in FLS INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 First Look Survey (FLS) S>0.115 mJy Multi-band information: opt. Spectra  MMT Hectospec MIR 24  m  Spitzer MIPS 1.4 GHz  VLA/WSRT 0.61 GHz  GMRT  MIR-Radio correlation: q24=log(S24/S1.4)=0.83±0.31  Spectral index:  (1.4-0.61)  3 RQ-AGN with S( 1.4 GHz ) > 0.115 mJy S( 1.4 GHz ) > 0.115 mJy [area=1 sq. degr.] Prandoni, Morganti+ in prep SFGs RL AGNs RQ AGNs SFGs RL AGNs RQ AGNs flat steep

7. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 III – Benefits of LOFAR 2.Low frequencies   steep sources (RQ-AGN)   Radio spectra in poorly explored freq. range S>10 microJy 0 1 2 3 240 MHz: 2 10 4 RS in PB [1.5 sq.deg.] @ 100-km LOFAR conf. limit of S>14  Jy 1. Large FoV  Large deep samples to probe evolution of low-P AGNs  constraints to AGN models for P< 10 24 W/Hz @ z<4 (RL-AGN + RQ-AGN component) (RL-AGN + RQ-AGN component) NB:Not only steep LLAGNs For flat AGNs LOFAR 240 MHz deep fields as faint as current VLA deep fields

8. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008 International bs increase resolution: High spatial resolution important  separate SB and AGN NB: sub-arcsec resolution  NB: sub-arcsec resolution  AGN/SF morphology on kpc scales AGN/SF morphology on kpc scales  embedded AGNs in SFGs (cfr. eMERLIN  0.15” @ 1.5 GHz)  embedded AGNs in SFGs (cfr. eMERLIN  0.15” @ 1.5 GHz) III- Benefits of E-LOFAR Max Freq. Angular Confusion Baseline resol. Limit (3  ) (km) (MHz) (“) (  Jy) 150 240 2.4 13 500 240 0.6 5 1000 240 0.3 1 S lim ~1  Jy S lim ~1  Jy  factor 10 lower P @ same z (sensitivity limited surveys)  Lower confusion limit (sensitivity limited surveys)

9. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008  General agreement between obs. data and models (PLE/LDE) More quantitative LLAGN modeling  larger deep radio samples (All-sky/degree scale LOFAR 240 MHz deep surveys)  At S>0.4 mJy & I 0.4 mJy & I<23.5 no evidence of a RQ-AGN component Probing the steep RQ-AGN component  deeper AGN surveys and/or lower frequency (  LOFAR)  (base-)Jet/Jet+ADAF scheme most plausible for compact flat- spectrum ETS Probing Accretion schemes  Obs. Follow-up e.g. multi-freq./high-res. radio obs. over large freq. range (for low freq. range  E-LOFAR) Summary [S lim  100  Jy]

10. INAF - ISTITUTO DI RADIOASTRONOMIA I. Prandoni – Sept. 2008