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A Bolometric Approach To Galaxy And AGN Evolution.

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). The Hawaii bolometric sample:.

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A Bolometric Approach To Galaxy And AGN Evolution.

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  1. 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)

  2. 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.

  3. The HDF /GOODS-N /CDF-N is still the best field for this!

  4. Wide Hawaii HDF-N Data

  5. 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)

  6. 503 X-ray sources:(purple crosses) 202 20cm Radio sources (red squares): rectangle is core GOODS region.

  7. 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).

  8. STATUS: Goal is a complete spectrosopic identification of the sample: currently 1890/2475 of the sources are spectroscopically identifiedand all but about 100 of these have high quality spectra. Red=X-ray AGN

  9. Redshift distribution of Z band sources

  10. Today I just want to focus on the analysis of the submillimeter light and its implications for the star formation

  11. HDF-proper HST ACS imaging GOODS HDF-N ~110 arcmin2 by SCUBA 0.4-4 mJy (rms) sensitivity ~ 95 hours integration 27 sources at >3.5 SCUBA Survey in the GOODS HDF-N SCUBA 850m map Wang, Cowie, & Barger (2004)

  12. radio sensitivity limit redshift desert Spectroscopy of 20cm Selected Submm Sources Chapman et al. (2005) 18 Keck nights ~ 100 submm sources observed ~ 70 identified median redshift = 2.2

  13. 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.

  14. Cowie, Barger, Kneib 2002 Weakly divergent EBL convergent fit Broken power law fit “Typical” source about 0.7mJy

  15. Stacking Analysis

  16. 850 m Stacking Analyses total 850 um EBL : 31-44 Jy deg-2 (COBE)

  17. Sd Irr ? E Sb Sc Submm EBL vs Spectral Type Intrinsically Red Intrinsically Blue

  18. core Near-IR sample Chapman et al. (2005) Submm EBL vs Redshift

  19. STAR FORMATION HISTORY: 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.

  20. Cosmic Star Formation History

  21. Cosmic Star Formation History (txMdot) Submm/20cm UV Mdot times t Integrated star density since Big Bang

  22. All of the backgrounds (including850 micron) have strong contributions from below z=1. However the UV and the 850 micron comefrom different galaxy populations. 850 850 micron UV 20 cm [OII]

  23. 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)

  24. Number Counts from Clusters • 0.3-2 mJy : • N(>S) = 3.5103 (S850/2 mJy)-1.2 deg-2 • = 20 (+32/-8) Jy deg-2 Cowie, Barger, & Kneib (2002)

  25. SuprimeCam 0.45°0.45 ° HDF-proper Capak et al. (2004)

  26. Spitzer Images GOODS Spitzer Legacy Program 20’  13’ Confusion limited at 3.6-4.5 m

  27. Extragalactic Background Light total 850 um EBL : 31-44 Jy deg-2

  28. AGN in the Z band sample

  29. Submm EBL vs Near-IR Color

  30. B<24 subsample:

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