AGN component in Deep Radio Fields Alessandro Maini co-tutelle PhD student Dipartimento di Fisica e Astronomia Università di Bologna & Istituto di Radio Astronomia INAF Department of Physics and Astronomy Macquarie University & Astronomy & Space Science Division CSIRO Main collaborators Giovannini G. Prandoni I. Parker Q. A. Norris R. P. 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 1 / 24 AGN component in Deep Radio Fields Outline Deep Radio Surveys and AGN component Focus on two populations: I - Radio-Quiet AGNs (RQ AGN) II - Infrared-Faint Radio Sources (IFRS) Future Perspectives 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 2 / 24 Deep Radio Surveys and AGN component The current picture S1.4 GHz down to ∼ 10 µJy 44th Young European Radio Astronomers Conference adapted from Norris R. P., 2012 (Proc. IAU Symp. 284, 2011, 489) ´ 8-12 September 2014 Torun, 3 / 24 Deep Radio Surveys and AGN component AGN Population decline Seymour et al., 2008 (MNRAS 386, 1695) S1.4 GHz ∼ 1 µJy ∼ 100 µJy ∼ 1 mJy ∼ 10 mJy AGN . 10% ∼ 30–40% ∼ 80–90% & 99% ∼ 90% ∼ 60–70% . 20% SFG Wilman et al. (2008) model 44th Young European Radio Astronomers Conference . 1% Windhorst et al., 1990 ´ 8-12 September 2014 Torun, 4 / 24 Deep Radio Surveys and AGN component AGN count Steady decline of Radio Galaxies and RL AGN flattening below 1 mJy due to RQ AGN Smolˇci´c et al. 2014 (PoS AASKA14 069) 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 5 / 24 I - Radio-Quiet AGN A new component adapted from Czerny B. et al., 2005 found in samples selected in X-ray, optical and MIR-bands (until recently!) radio emission negligible part of the bolometric luminosity 44th Young European Radio Astronomers Conference Sradio Soptical ´ 8-12 September 2014 Torun, ∼ 10 6 / 24 I - Radio-Quiet AGN A new component Bonzini et al., 2013 MNRAS 436, 3759 S1.4 GHz ∼ 1 µJy ∼ 100 µJy ∼ 1 mJy ∼ 10 mJy RL AGN . 10% . 30% ∼ 80–90% & 99% RQ AGN ∼ 20% ∼ 20% . 10% 1% SFG ∼ 70% . 50% . 10% . 1% 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 7 / 24 I - Radio-Quiet AGN Open issues The origin of the radio emission in deep-field RQ AGNs is still matter of debate: scaled down version of RL AGNs? (Miller et al. 1993; Giroletti & Panessa 2009; Prandoni et al. 2010, Jarvis & Rawlings 2004) ongoing star formation activity in the host galaxy? (Sopp & Alexander 1991; Padovani et al. 2011; Bonzini et al. 2013) mixed contribution from AGN and SF processes to the total radio emission? (Daddi et al. 2007; Gruppioni et al. 2011; Del Moro et al. 2013) 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 8 / 24 I - Radio-Quiet AGN Implications Disentangling the origin of the radio emission in RQ AGNs would have relevant implications on general topics like: triggering mechanism of AGN radio activity and its duty cycle; role played by low-accretion/radiative efficiency AGN activity in the global black hole accretion history of the Universe; relative contribution of radiative versus jet-driven (kinetic) feedback to the global AGN feedback in galaxy formation and evolution models. 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 9 / 24 I - Radio-Quiet AGN The project: searching for a compact radio core P.I.: Co.I.: Maini A. Prandoni I. Norris R. P. Giovannini G. Parker Q. A. Extended Chandra Deep Field South (E-CDFS) 7 RQ AGNs 9 RL AGNs (flux densities 200–400 µJy) Completed 20.5 h of the requested 72 h Australian LBA + Data reduction: ongoing... ASKAP resolution .20 mas 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 10 / 24 II - Infrared-Faint Radio Sources Serendipitously identified by Norris et al. (2006) and Middelberg et al. (2008) cross-matching catalogues of: Australia Telescope Large Area Survey (ATLAS) 5σ sensitivity limit: ∼0.2 mJy at 1.4 GHz Spitzer Wide-area IR Extragalactic Survey (SWIRE) 5σ sensitivity limits: 3.7 µJy at 3.6 µm (IRAC bands) 5.4 µJy at 4.5 µm 48 µJy at 5.8 µm 37.8 µJy at 8.0 µm 0.23 mJy at 24 µm (MIPS bands) 18 mJy at 70 µm 150 mJy at 160 µm in the CDFS and in the ELAIS-S1 deep fields All ATLAS source was expected to have SWIRE counterpart within z ∼ 2 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 11 / 24 II - Infrared-Faint Radio Sources ∼50 sources were undetected at ANY SWIRE band ATLAS = 0.14 → 26.08 mJy S20cm q24 = log S24µm S20cm = 0.84 ± 0.28 Appleton et al. (2004) No standard SFGs Sradio /SIR more consistent with AGN low SIR ⇒ very obscured and/or high redshift 44th Young European Radio Astronomers Conference Adapted from Norris et al. 2006 (AJ 132, 2409) ´ 8-12 September 2014 Torun, 12 / 24 II - Infrared-Faint Radio Sources VLBI and spectral analyses Norris et al. (2007) & Middelberg et al. (2008): core size < 0.030” 6 TB & 10 K ⇒ linear size . 260 pc ⇒ P1.4GHz ∼ 1025÷28 W/Hz (z ∼ 1 ÷ 7) ⇓ RL AGN / QSO regime IFRS ES0427 Middelberg et al. 2008 (A&A 491, 435) ELAIS-S1 population α ˜ 2.3 1.4 = −0.86 AGN ELAIS-S1 sample α ˜ 2.3 1.4 = −0.82 IFRS sample α ˜ 2.3 1.4 = −1.40 HzRG sample α ˜ 2.3 1.4 = −1.02 ⇓ Middelberg et al. 2011 (A&A 526, A8) 44th Young European Radio Astronomers Conference High redshift ´ 8-12 September 2014 Torun, 13 / 24 II - Infrared-Faint Radio Sources The sample Spitzer Extragalactic Representative Volume Survey (SERVS) 5σ sensitivity limits: 1.9 µJy at 3.6 µm 2.2 µJy at 4.5 µm New selction criteria: S1.4 GHz S3.6µm ≥200 Field unresolved at the SERVS PSF (1.9”) Covered Original From 3.6 µm band Area Number sources IFRSs 2 Name (deg ) in field detected claimed reliable CDFS 4.5 22 Norris+ (2006) 21 8 7 4 ELAIS-S1 3.0 29 Middelberg+ (2008) 17 6 4 4 ELAIS-N1 2.0 18 Banfield+ (2011) 5 3 2 1 XMM-LSS 4.5 3 Zinn&Oliver (in prep.) 3 – – – LH 4.0 21 Maini+ (sub.) 21 11 11 11 Total 93 67 28 24 20 44th Young European Radio Astronomers Conference 4.5 µm band sources IFRSs in field detected claimed reliable 21 7 6 5 14 5 3 3 5 3 2 1 3 – – – 19 10 10 10 62 25 21 19 ´ 8-12 September 2014 Torun, 14 / 24 II - Infrared-Faint Radio Sources Evolutionary tracks 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 15 / 24 II - Infrared-Faint Radio Sources Evolutionary tracks 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 16 / 24 II - Infrared-Faint Radio Sources A sub-class of the RL AGNs? Adapted from Collier et al. 2014 (MNRAS 439, 545) 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 17 / 24 II - Infrared-Faint Radio Sources Implications A good assessment of IFRS nature and density would help to: pinpont the highest-z AGN populaton in large surveys constrain the AGN number density at high z constrain the structure formation scenario up to the reionization epoch 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 18 / 24 Deep Radio Surveys and AGN component Future Perspectives courtesy Prandoni I. S1.4 GHz down to sub-µJy / nJy level 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 19 / 24 AGN component in Deep Radio Fields Thank you for your attention 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 20 / 24 Infrared-Faint Radio Sources Appendices 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 21 / 24 Infrared-Faint Radio Sources Appendices 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 22 / 24 Infrared-Faint Radio Sources Appendices 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 23 / 24 Infrared-Faint Radio Sources Appendices LH324 LH2633 3.6 µm 3.6 µm 4.5 µm 4.5 µm 44th Young European Radio Astronomers Conference ´ 8-12 September 2014 Torun, 24 / 24
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