1 OABo days The physics, environment and evolu/on of early supermassive black holes R. Gilli Some fundamental ques/ons: At what epoch did the ﬁrst genera/on of SMBHs form? What is their origin (e.g. light vs heavy seeds)? Where and how early seeds could grow to SMBHs? Do BHs form before their hosts? Who re- ionized the Universe? SDSS J1148, z=6.43
2 Main collabora/ons Large Interna/onal Collabora/ons 7Ms Chandra Deep Field South (PI N. Brandt, PSU) COSMOS- Legacy (PI F. Civano, CfA) Intra- INAF (Massardi, Mignano,...) Intra- OABo Comastri, Mignoli, Calura, Vanzella, Balmaverde, OABo- DIFA Vignali, Brusa, Lanzuisi, Pozzi, OABo group ARC DIFA group CDFS + COSMOS Other collaborators Vito*, Cappellu/*, Iwasawa, Norman, Chiaberge, Rosa/, Sani, +++ un/l fall 2015 Focus on projects led by OABo since the past two years
3 z=3.1 z=3.3 z=3.7 AGN XLF within CDFS+COSMOS z=4.1 z=4.5 Vito+14 AGN space density φ(z) ~ (1+z) - 6 ~1 dex decrease from z=3 to z=5 just like brighter SDSS QSOs Next steps: extend to lower L x (Vito+ in prep) if same trend, AGN likely do not reionize the IGM (as opposed to recent claims, e.g. Giallongo+15)
4 within CDFS+COSMOS Obscured AGN frac/on at z>3 The frac/on of obscured QSOs increases with redshio z=3.5 z=0.1 Half of z>3 AGN are obscured by logn H >23 At high- z, higher gas frac/on and merger rate (Menci+08, Lamastra+10). In addi/on, galaxies are more compact! Increasing absorp/on by host ISM? Vito+14
5 The case of XID403 in the CDFS: an SMG at z=4.75 hos/ng a Compton- thick QSO with ARC (and DIFA) Chandra spectrum N H = x 1024 cm - 2 L x ~ 3 x erg/s 6Ms ALMA Cycle 0 detec/on Gilli+14 4Ms filler target, S/N ~ 35 in 3 min marginally resolved at ~0.7 res.! r 50%,dust ~ 0.9 ± 0.3 kpc ALMA constrains size of dust/sf
6 with ARC (and DIFA) FIR and broad band SED our 1.3mm M dust = 4.9 (± 0.7) x 10 8 M sun r 50%,dust ~ 0.9 (± 0.3) kpc (0.3 or less) M * = 1.1 x M sun M gas ~ 2x10 10 M sun (De Breuck+14) N gas = x cm - 2 comparable with X- rays BH may be obscured by host ISM Z = Z sun (Nagao+12) SB stars AGN
7 ALMA Cycle 0 sta/s/cs (Stoehr+15, arxiv ) with ARC (and DIFA) Pressure on EU /me in Cycle 0 ~ 10x we are here Next steps: Keep proposing similar targets for ALMA (other fillers accepted in both Cycle 2 and 3 but not observed), mine the ALMA archive (excellent resource, especially in CDFS) Keep fruiwul collabora/on with Bologna ARC
8 M dust, M *, M dyn Intra- OABo (+ DIFA) XID403 3x10 11 Larson IMF M bary =10 12 M sun x10 10 M * from SED fixng 1 dex larger than from M dyn by De Breuck+14 M dust is ok with M * from SED- fixng Calura+14: sample of 58 QSOs at z~6 with FIR observa/ons: measured M dust ooen too large to be produced by a system with the measured M dyn
9 Overdense region Average density region Intra- OABo (+ DIFA) Environment of z~6 QSOs z=6.2, Costa+14 comoving HST/ACS 1 Mpc Overdensi/es might extend up to 30arcmin around QSOs (Overzier+09)! need wide field observa/ons comoving FoV ~ 25 x25, etendue 111 m 2 x 0.15 deg 2 is the only compe/tor
10 Search for galaxy overdensi/es around z~6 QSOs extensive use of LBT i- band dropouts (i.e. z~6 LBG canditates) selected around 4 SDSS QSOs at z~6 with MBH>109 Msun LBC blue LBC red 1.5 hr isdss 3 hr rsdss Target Intra- OABo (+ DIFA) 1.5 hr zsdss z M1450 SDSSJ SDSSJ SDSSJ SDSSJ Morselli+14 data products available at: hzp://oabo.inaf.it/~lbtz6
11 Intra- OABo (+ DIFA) Primary cand. Secondary HST/ACS QSO Frequency Field i- drop- obs. i- drop corr. δ σ δ J J J J SXDS 4.3 The significance of the overdensi/es combined over the four fields is 3.7σ! early QSOs do live in dense fields
12 Intra- OABo (+ DIFA) Recently acquired or planned op/cal/ir follow- ups Observa?on Op/cal MOS on J1048, J1148, J1411 addi/onal rizy imaging in J1148, and riz in J1141 (z AB ~26, 5σ) J- band imaging on J1141 and Y,J imaging on J1030 (AB ~24, 5σ) near- IR spec. on ID3605 in the J1148 field X- rays on J1030 (to f 05-2 ~10-16 cgs) Telescope/ Instrument Exposure?me Status MODS- LBT 30hr Data received, analysis just completed LBC- LBT 26hr Data received, analysis on- going WIRCAM- CFHT 9hr Data just received, analysis on- going LUCI- LBT 8hr Data just received, analysis on- going Chandra ACIS- I 500ks To be observed
13 Op/cal spectroscopy with (just completed) SDSSJ1048 field (z=6.2) Intra- OABo (+ DIFA) SDSS J1148 field (z=6.42) ID3605: primary dropout at z=6.456 ID4811: primary dropout at z=5.9 Lyα Δz=0.3 " Δr=18 pmpc? ID2277: secondary dropout at z=5.7 separa/on of ~ 4 pmpc from QSO " if confirmed, same LSS
14 Intra- OABo (+ DIFA) Chandra LP (500ks ACIS- I) on J1030 approved in Cycle 17 Chandra largest program for INAF Scien/fic Goals (sorted by decreasing risk)!""#$%&'$ ()*$ 1) detec/on of faint satellite AGNs " growth of SMBHs in early LSSs 2) high quality spectrum of SDSSJ1030, 550 cts " ionized iron features, Γ, UFOs 3) deep mul/- λ survey: 200 X- ray sources down to erg/cm 2 /s ; MUSYC + LBT + WIRCAM + Spitzer = UBVRIzYJHK,IRAC,MIPS
15 Next cri/cal steps Intra- OABo (+ DIFA) The spectroscopic campaign is indica/ng that bright (z AB <25) i- band dropouts must have weak (if any) Lyα emission " need other strategies to secure their redshios and verify whether they belong to the QSO LSS (i.e. Δz~0.1, or Δr~10 pmpc) Mul/- λ obs for photo- zs or color- color plots necessary but not sufficient. Hence: stellar locus robust LBG candidates - apply for deep op/cal spectroscopy to detect the con/nuum break, e.g hr with - apply for ALMA observa/ons of the [CII]158μm emission line (bright dropouts likely massive, dusty and metal- rich systems).
16 Intra- OABo (+ DIFA) Personnel Staff: R. Gilli, M. Mignoli, E. Vanzella Postdoc: B. Balmaverde, 1yr AdR, started Feb 1st INAF PhD fellowship granted aoer 3 trials but DIFA could not allocate it, grant lost. Try again in cycle XXXII. 1 AstroFit2 applica/on to work on this project (on the theory side) pending Funding Funds from PRIN- INAF 2012 expired, no funds currently dedicated to this project (the allocated NASA/Chandra grant of 73 k$ cannot flow to non- US researchers) PRIN- INAF? ASI- INAF?