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A Bolometric Approach To Galaxy And AGN Evolution. L. L. Cowie Venice 2006 (primarily from Wang, Cowie and Barger 2006, Cowie and Barger 2006 and Wang 2006 thesis)
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The Hawaii bolometric sample: To understand the star formation and accretion history we need a census of all energy-producing galaxies & supermassive black holes in the universe, including those obscured by gas & dust. Best to choose them by their bolometric light rather than at a single frequency.
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The HDF /GOODS-N /CDF-N is still the best field for this!
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Wide Hawaii HDF-N Data BandSensitivity LimitTelescope / CameraSource (5sig Jy) U0.052KPNO 4mCapak et al. (2004) B0.063Subaru / SuprimeCamCapak et al. (2004) V0.069Subaru / SuprimeCamCapak et al. (2004) R0.083Subaru / SuprimeCamCapak et al. (2004) I0.209Subaru / SuprimeCamCapak et al. (2004) z’0.251Subaru / SuprimeCamCapak et al. (2004) J0.839UH2.2m / ULBCAMTrouille et al. (2006) (400 sq arcmin) H1.06UH2.2m / ULBCAMTrouille et al. (2006) 3.6 m 0.327Spitzer / IRACGOODS Spitzer Legacy Program 4.5 m 0.411Spitzer / IRACGOODS Spitzer Legacy Program 5.8 m 2.27Spitzer / IRACGOODS Spitzer Legacy Program 8.0 m 2.15Spitzer / IRACGOODS Spitzer Legacy Program 24 m 80Spitzer / MIPSGOODS Spitzer Legacy Program
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Just under 4000 galaxies have been spectroscopically identified in the region: remainder can be assigned photometric redshifts. J and H data considerably improves the robustness at z>2. Spectroscopic redshifts (as of early 2006)
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503 X-ray sources:(purple crosses) 202 20cm Radio sources (red squares): rectangle is core GOODS region.
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HAWAII BOLOMETRIC SAMPLE: 2740 objects with 0.3-24 micron fluxes above 1.5x10^(-14) erg cm^(-2) s^(-1) in the 140 square arcminute core GOODS region. This already contains all but 5 of the 40 microJy radio sources and all but 3 of the X-ray sources (CDF-N). We add the remaining 7 sources (2 are overlapped). Goal is a near-complete spectrosopic identification of the sample: with a uniform 4000-10000A spectral database (DEIMOS spectrograph) of very high quality and spectral resolution. Sample contains all of the 24 micron sources (this determines the limiting flux).
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STATUS: Goal is a complete spectrosopic identification of the sample: currently 1890/2475 of the sources are spectroscopically identified and all but about 100 of these have high quality spectra. Red=X-ray AGN
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Redshift distribution of Z band sources
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Today I just want to focus on the analysis of the submillimeter light and its implications for the star formation
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SCUBA Survey in the GOODS HDF-N GOODS HDF-N ~110 arcmin 2 by SCUBA 0.4-4 mJy (rms) sensitivity ~ 95 hours integration 27 sources at >3.5 Wang, Cowie, & Barger (2004) HDF-proper SCUBA 850 m map HST ACS imaging
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Spectroscopy of 20cm Selected Submm Sources redshift desert radio sensitivity limit Chapman et al. (2005) 18 Keck nights ~ 100 submm sources observed ~ 70 identified 2.2 median redshift = 2.2
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Problems Submm sources that are above SCUBA’s detection limit (~2 mJy) only contribute ~20% of the total submm background. Only 60% of the above 20% can be detected by radio telescopes to 40 microJy at 20cm. Chapman’s radio selected submm sources only represent ~10% of the total background. Need to know about the faint (<2mJy) sources.Need to know about the faint (<2mJy) sources.
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Cowie, Barger, Kneib 2002 Broken power law fit EBL convergent fit Weakly divergent “Typical” source about 0.7mJy
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Stacking Analysis
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850 m Stacking Analyses BandN I (mJy)(Jy Deg -2 ) ULB 1.6 m 3094 0.20 0.0318.3 2.4 IRAC 3.6 m 5245 0.11 0.006619.6 3.4 MIPS 24 m 493 0.66 0.0611.4 1.1 VLA 20 cm101 1.31 0.134.0 0.40 1.6 m + 3.6 m 1783 24.0 2.0 total 850 um EBL : 31-44 Jy deg -2 (COBE)
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Submm EBL vs Spectral Type Sb Sc Sd Irr E ? Intrinsically Red Intrinsically Blue
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Submm EBL vs Redshift core Near-IR sample Chapman et al. (2005)
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Compute star formation rates from measured 20cm fluxes of all the sources contributing to the submillimeter light (the core sample). Compute average radio power of the sample in each redshift interval. Assumes FIR-radio correlation but avoids assumptions about dust temperature. STAR FORMATION HISTORY:
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Cosmic Star Formation History
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Cosmic Star Formation History (txMdot) UV Submm /20cm since Big Bang Mdot times t Integrated star density
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All of the backgrounds (including 850 micron) have strong contributions from below z=1. However the UV and the 850 micron come from different galaxy populations. UV [OII] 850 micron 20 cm
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Summary We detect most (60%-80%) of the submm EBL using the near-IR population. Most of the submm EBL comes from intermediate type galaxies at z ~ 1. (Not the same sources that dominate the UV) Star formation history peaks at z ~ 1 and is flat at z > 1. Wang, Cowie and Barger, 2006 astro-ph/512347 (ApJ upcoming) The bolometric sample will appear shortly in Cowie and Barger (2006)
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Number Counts from Clusters 0.3-2 mJy : N(>S) = 3.5 10 3 (S 850 /2 mJy) -1.2 deg -2 = 20 (+32/-8) Jy deg -2 Cowie, Barger, & Kneib (2002)
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SuprimeCam 0.45° 0.45 ° Capak et al. (2004) HDF-proper
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Spitzer Images GOODS Spitzer Legacy Program 20’ 13’ Confusion limited at 3.6-4.5 m
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Extragalactic Background Light total 850 um EBL : 31-44 Jy deg -2
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AGN in the Z band sample
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Submm EBL vs Near-IR Color
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B<24 subsample:
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