Dust emission from powerful high-z starbursts and QSOs

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1 Dust emission from powerful high-z starbursts and QSOs Alain Omont (IAP) Substantial and most spectacular star formation at z > 1 The hidden part of the evolution of most massive galaxies and black-holes Multi-λ interplay between mm at IRAM with optical surveys, SCUBA and Spitzer + The Scientific Future of IRAM (Pierre Cox cancelled talk)

2 Dust emission from powerful high-z QSOs and starbursts General goals OUTLINE Background: High z submillimeter galaxies (SMGs) Millimeter dust and CO detection in SMG hosts of high z QSOs Other IRAM studies of high-z SMGs Projects Identification of high-z Type 1 & 2 QSOs in CFHTLS data Identification of SMGs in SWIRE and other wide Spitzer surveys Prospects [Herschel (L. Vigroux)] ALMA The Scientific Future of IRAM (Pierre Cox)

3 SMGs: strongest starbursts in the Universe Giant starbursts at the peak of elliptical formation z ~ At least Ultra-Luminous Infra-Red Galaxies (ULIRGs): L FIR >~ Lo, SFR > 100 Mo/yr Relatively rare, but ~1 per arcmin 2 Generally not isolated; strongly biased along high-z Large Scale Structures Probably progenitors of massive elliptical galaxies A few of these objects are powerful QSOs or radiogalaxies M BH >~ 10 8 Mo Most exceptional Hyper-Luminous IR Galaxies (HLIRGs): L FIR >~ Lo, SFR ~ 1000 Mo/yr Nothing equivalent in the local Universe Very rare ~1 per 100 arcmin 2 CO already detectable Probably in most massive DM halos progenitors of central cd galaxies of clusters A fraction of them are very powerful QSOs or radiogalaxies M BH >~ 10 8 Mo

4 Landmarks and questions of the evolution of most massive galaxies and associated super-massive black-holes Final mass Mo z ~ 4-10 Major starbursts in the 1st billion yr at DM density peaks (first LSSs) LBGs & Lyα Galaxies SMGs: ULIRGs & HLIRGs? Final black-hole mass Mo First SMBHs M BH ~ 10 9 Mo A few most powerful QSOs z=6.4 Fewer Radio Galaxies z >~4 1.5 ~< z <~ 3 Peak of starburst SMGs SCUBA/MAMBO counts Mergers & pre-clustering? CO detection Detection in Spitzer wide surveys + Distant Red Galaxies? z < Decline of SMGs mostly passive evolution (+stellar mergers) massive elliptical galaxies + supermassive cd cluster galaxies QSO Feedback Major phase of SMBH growth Peak of QSO activity Weak AGN activity in most SMGs X-absorbed QSOs and Type 2 QSOs Spitzer IR QSOs? SMBH mergers? Very few powerful QSOs Dormant most massive SMBHs

5 Dust detection: The Magic of the high-z submm window FIR emission of cold dust (T d ~ K) : - steep submm spectrum - compensates for distance - Sν practically independent of z from z ~ 0.5 to 10 Redshift degeneracy Effect also known as «negative K correction» L fir = 4x10 12 S 250 (mjy) L sun from Bertoldi, Voss, Walter

6 Dust detection: the magic of the submm window SCUBA(-MAMBO) census of high-z ULIRGs Take advantage of steep submm spectrum Account for most of submm background z at Keck for radio ones (~50%) (weak AGN?) History of star formation up to z~3-4 Small but uncertain number at z > 4 SCUBA (+MAMBO) submm counts SCUBA(-radio) redshift distribution Chapman, Blain, Ivison, Smail 2003

7 High-z millimeter studies at IRAM 1. MAMBO detection of redshifted far-ir/submm dust emission from high-z QSOs A. Beelen F. Bertoldi C. Carilli P. Cox + J. Bergeron, K. Isaak, R. McMahon, R. Priddey, etc. Omont et al Carilli et al Omont et al 2001 Omont et al 2003 Bertoldi etal Beelen et al CO detections with the Plateau de Bure Interferometer

8 MAMBO/IRAM detection of redshifted far-ir/submm dust (and CO) emission from high-z QSOs Aims To establish correlations between major starbursts and black-holes at high z It is the easiest way to find (biased) cases of ULIRGs at very high z, since the redshifts of SCUBA/MAMBOsources are practically unknown at z > 4 It is thus better to search similar sources around known objects: (bright) QSOs Sample More than 200 mostly bright QSOs L bol ~ Lo M B ~ ), with z~2-6, from optical surveys: PSS, SDSS, etc. Observations IRAM 30m Telescope (Granada, Spain) + MAMBO bolometer cameras built at MPIfR Bonn (E. Kreysa)

9 MAMBO/IRAM detection of redshifted far-ir/submm dust (and CO) emission from high-z QSOs Summary of results (very similar to bright Scuba SMGs) High rate of detection : ~55 sources detected ~ 25% No significant dependence of the far-ir luminosity on z The mm/submm emission is dominated by cold dust at K L FIR ~ Lo HLIRGs SFR ~ 1000 Mo/yr Heating of cold dust by starburst or AGN, or both? Both are viable; probably a combination of both in various proportions, but some starburst is probably always present in the sources detected at 1.2 mm (CO detections in some sources) The far-ir luminosity is weakly correlated with rest UV L bol

10 Significant fraction of observing time devoted to detecting ~30 high z galaxies in recent years Plateau de Bure IRAM interferometer

11 CO detection in 14 high-z QSOs CO detection in QSO SDSS J1148 at z=6.42 Dense gas density ~10 5 cm -3 T ~ 100 K size R ~ pc gaz mass Mo Multi-line excitation model Bertoldi et al. 03 PdBI Resolution of CO in 2 sources VLA Walter et al. 04 Walter et al. 03 VLA

12 Other IRAM studies of high-z SMGs 1. High-z Radiogalaxies CO detection in 5 radiogalaxies at z ~ 3-4 De Breuck, Papadopoulos, Omont, Ivison, Downes, etc. - Much broader lines (500 to > 1000 km/s) than in QSOs ( km/s) - Several objects with two CO components in position/velocity in pre-merging stage? Overdensity of MAMBO SMGs around two radiogalaxies at z ~ 3-4 De Breuck, Bertoldi, Omont, Ivison et al mm MAMBO study of z~0.6 SDSS Type 2 QSOs Strauss, Zakamska et al. Five 2-3-σ detections 3. CO detection in 11 SCUBA SMGs Large program at IRAM Interferometer Greve, Neri, Chapman, Genzel, Ivison, Bertoldi, Smail Blain, Cox, Omont, Tacconi, Kneib

13 Molecular Gas in SCUBA submm Galaxies 1 < z < 3.5 <M(H2)> = Msun ~5 times more gas and luminous, than local ULIRGs Broad FWHM linewidth Complex/interactive environment (+weak AGN) M gas significant fraction of central mass Greve et al. (2004)

14 Current conclusions of our study of our high-z QSO-hosts HLIRGs in the light of SMG studies and feedback models for QSO/spheroids Such huge starbursts exist at least up to z=6, and our sample is by far the largest one of ULIRGs at z>4 In the feedback model, they should be in the terminal phase of the ULIRG/AGN episode; both the starburst and the QSO should soon stop, starved of gas (maybe waiting for the next major merger) The near independence of <L FIR > from L bol should result of some compensation between the QSO destructive action and the stability of the starburst depending on the spheroid mass, not yet fully clear The recent X-Ray results of Oliver et al explain well the growth of black-holes during the SMG phase up to 10 8 Mo. It would be interesting to check whether and which SMGs allow them to grow up to 10 9 Mo

15 ALMA high-z capabilities in brief (see Viallefond s talk) ~50 times more sensitive than present Census of LIRGs at ALL z Detailed studies of ULIRGs (> Lo) at ALL z 12 Lo High resolution 0.1 images in continuum and lines (CO, C +, etc.) + Heterodyne spectral resolution Mm determination of redshifts No confusion limitation Submm full SED of cold dust Etc.

16 Projects 1. Identification of high-z QSOs in CFHTLS data Pei Yu, J. Bergeron, X.L. Liu z ~ 6 Type I QSOs in Wide and Very wide CFHTLS surveys z ~ 4 Type 2 QSOs in the Deep CFHTLS survey 2. Identification of SMGs in SWIRE and other wide Spitzer surveys

17 Prospects of CFHTLS for z~6 QSOs One great achievement of SDSS is the discovery of z~6 QSOs (~ ) Implication for early black-hole growth Reionization not yet complete (Gunn-Peterson effect) The CFHTLS Wide Survey is ~4 magnitude deeper than SDSS (in 170 deg² instead of deg²) Luminosity Function whole QSO range ~30-40 identifications of z~6 QSOs expected in 170 deg² of CFHTLS Wide Larger number in 900 deg² of CFHTLS Very Wide if z observations

18 z ~ 4 Type 2 QSOs in the Deep CFHTLS survey (J. Bergeron) Type 2 QSOs are initially identified from X-ray/optical luminosity ratio Optical identification from AGN Narrow Lines but (quasi-)absence of Broad Lines maybe relatively inhomogeneous class Optical continuum only slightly different from Lyman Break Galaxies (LBGs) A few percents of z=2-3 LBGs (Steidel et al.) ~50 expected in the 4 deg² of CFHTLS-Deep (and 2000 in the CFHTLS-Wide) Find them among z=4 g dropouts: color criteria VLT spectroscopy Extension to pre-clustering of z=4 LBGs

19 z ~ 4 Type 2 QSOs in Deep CFHTLS survey Possible related studies in CFHTLS Deep-Fields (D1) Pre-clustering of z=3 Type 2 QSOs and LBGs ( z=1-2) Combined with identification of Type 2 QSOs from Spitzer/SWIRE Combine variability studies in D1 Field from CFHTLS-SNLS with SWIRE data (E. Aubourg et al.) : in preparation Spitzer mid-ir variability ( proposal submitted, E. Aubourg et al.)

20 Projects 1. Identification of high-z QSOs in CFHTLS data 2. Identification of the many strong SMGs well detected in SWIRE and other wide Spitzer surveys Large program submitted to IRAM with broad European + SWIRE collaboration (Lonsdale, Cox, Lagache, Dole, De Breuck and many others)

21 Identification of SMGs in SWIRE Direct Spitzer detections of ~20 SCUBA/MAMBO SMGs at z~2 confirm that SWIRE should practically detect all SMGs with S(850µm)> 5-10 mjy, i.e. several hundreds per deg² several 10 4 in total ~100 times more than all existing MAMBO-SCUBA surveys MAMBO proposal submitted to IRAM: detect SWIRE HLIRGs candidates at 1.2mm long term aim to identify all >~1000 SWIRE HLIRGs (S(850µm)> 12 mjy tracing most massive galaxies, massive DM halos & exceptional (lensed) objects detailed follow-up IRAM studies of best cases SWIRE Limit HLIRGs Careful identification criteria of HLIRG candidates from SWIRE+ optical data + SMG SED templates Difficult extrapolation from 24µm long term effort Full identification of SWIRE z~2 ULIRGs + HLIRGs warranted with Herschel

22 The Scientific Future of IRAM Pierre Cox 1. IRAM and its Telescopes: Science & Instrumentation at the 30-meter and the Plateau de Bure Interferometer 2. Mid-Term Plans 3. Long-Term Plans

23 Spitzer Space Telescope APEX ALMA 6 Herschel/Planck LMT CARMA ALMA 64 JCMT CSO SMA 30-meter Plateau de Bure

24 Options for the 5-years Plan at the 30-meter BETTER HETERODYNE RECEIVERS LARGER FOCAL PLANE BOLOMETER ARRAYS The 30-meter will remain for the years to come the prime single dish telescope operating at mm wavelengths.

25 The Next Generation of Receivers at the PdBI ( ) New generation receivers Improved Sensitivity: ~2 for Spectroscopy and ~5 in Continuum as compared to the current system Improved Frequency Coverage & Imaging Extension of the baselines: HPBW of 0.3 arcsec at 230 GHz

26 Millimeter Wave Interferometers in 2007

27 Long-Term Options >2008 PICO VELETA Large bolometer arrays (>1000/2000 pixels) / photometric sensit. Large heterodyne arrays Increase the instantaneous bandwidth (16 GHz per polar) Key role to play in combination with PdBI (short spacing) PLATEAU DE BURE INTERFEROMETER Focal Plane Arrays (9 or 16 pixels) at 3 or 2 mm Increase the instantaneous bandwidth (to 8 or 16 GHz) More sensitive receivers (factor of 1.4) Further extension of the EW baseline to 1.5 km/ Additional antenna. Cooperation with CARMA ( software merging )

28 Conclusion The mm/submm range is essential to study the major starbursts of the assembly of the most massive galaxies and their relation with the growth of their super-massive black-hole Such most extreme objects have no equivalent locally, but they are major actors in the evolution of the Universe at z ~2-3 One needs larger samples of HLIRGs to explore the bright end of the SMG luminosity function, their properties and evolution New multi-λ surveys, such as CFHTLS and SWIRE, provide powerful and unique tools to identify high-z starbursts and AGN, possibly dusty, such as Type 2 QSOs and HLIRGs This field will strongly develop in the near future in particular with Herschel, the new generation of submm cameras and especially ALMA IRAM should remain the best millimeter facility for almost a decade before ALMA and the next generation of single dishes such as LMT (but GBT & EVLA)

29 Mid-term projects summary decided open options New generation single-pixel receivers PdB New IF processor (PV) IF transport with opt fibers (PdB) New correlator (PdB) WVR corrections Track extension (PdB) New subreflector (PV) New bolo camera (MPIfR) New gener. single-pixel receivers for PV Improved wobbler (PV) Extension of HERA 1.3- mm FPA Second station on E track E68 or extension towards West (PdB)

30 Ordering the Long-Term Options Moderate Investment: Dedicated facility Legacy-type projects around key scientific topics: surveys, mapping projects, northern sky sources etc. Preparatory work for ALMA Ambitious Investment Large focal plane arrays both at the 30-meter (heterodyne and bolometers) and the PdBI (9 or 16 pixels heterodyne arrays) Extension of the EW baseline to 1.5 km [& Additional Antenna.] Broader Bandwidth Receivers for PdBI Increase in sensitivity, angular resolution, imaging speed & flexibility. Will ensure that IRAM remains a key facility serving the community to execute top level science and motivate and develop innovative technological developments.

31 The site of the Atacama Large Millimeter Array Cerro Chajnantor altitude 5000m in Atacama desert, northern Chile, close to Bolivia+Argentina border High resolution configuration Compact configuration Work has begun

32 ALMA : General references and web sites ALMA web sites: - NRAO - ESO - Japan «Science with ALMA» : ALMA Design Reference Science Plan (DRSP): Omont, A., 2003, «The promise of ALMA» astro-ph Omont, A., 2005, «The promise of ALMA for unraveling the high-z Universe» xxx

33 z D phot (Gpc) z= z= Main z ranges in the Cosmic History of galaxies ~ 300 million ~ 3.5 billion z ~ 7 20? - Reionization PopIII stars +1st galaxies -Formation of 1st galaxies Pop. II stars - First AGN z ~ 4 7 : Current frontier - Galaxy and Black-Hole early assembly - End of reionization z ~ 1.5-4: - Peak of star formation submm sources + LBGs -Peak of QSO activity -Luminous mid-ir sour. -Proto-cluster formation z ~ : Final phase of active SF - Mid-IR sources - Weak X-ray AGN - Cluster formation

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35 Some kind of «negative K correction» also exists for CO detection: at λ fixed (3mm window) ) J of redshifted detected line increases with z: CO lines High-z CO Detectability J=1-0 at z=0 J=5-4 at z=5 the line luminosity strongly increases with J, as long as the level is excited Continuum submm radiation z=0.1 z= J=1-0 3mm window z= F.Combes, Maoli, Omont CO rotation lines

36 CFHTLS at a glance Survey deg² filters depth total exposure nights Vega mag (dark) Very Wide * 1300 r' mn Ecliptic strip g' mn Optimized for KBO detection i' mn 110 Wide Synoptic 170 u* s g' s W1: ; W2: ; W3: ; r' i' z' s 4300 s 7200 s 162 Deep Synoptic 4 u* hr g' hr D1 02h 26m 00s -04d 30m 00s D2 10h 00m 29s 02d 12m 21s D3 14h 19m 28s +52d 40m 41s D4 22h 15m 31s -17d 44m 00s r' i' z' hr 132 hr 66 hr 202