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  1. The Cosmic Star Formation and Metallicity History Lisa Kewley Hubble Fellow U. Hawaii with C. Kobulnicky (U.Wyoming), S. Ellison (U. Vic), M. Geller (CfA), R. Jansen (ASU)

  2. Summary • Motivation • Star Formation Rates • Cosmic Star Formation History • Metallicity diagnostics • Cosmic Metallicity History • Conclusions & Future Directions

  3. Motivation Galaxy Evolution Image credit: R. Thompson, NASA Image credit: NASA

  4. Star Formation History Madau et al. (1996) Lilly et al. (1996)

  5. [OII] Optical Spectrum SFR measured in infrared, optical, radio, UV, X-rays

  6. Optical Spectrum disagreement SFR measured in infrared, optical, radio, UV, X-rays

  7. Star Formation Rate Discrepancies Teplitz et al. (2003) filled = [OII] unfilled = Ha

  8. Norman et al. (2003) 0 Teplitz et al. (2003) UV [OII] Ha IR radio comb -0.5 + + -1 + * * -1.5 x * log (MO / yr / Mpc3) . x -2 -2.5 0.2 0.8 0 0.4 0.6 Star Formation Rate Discrepancies SFR Density Redshift

  9. Towards SFR agreement Nearby Field Galaxy Survey (NFGS) • Jansen et al. (2000,2001) • 198 galaxies objectively selected from the CfA galaxy survey • (Davis & Peebles 1983, Huchra et al. 1983) • full range in Hubble type • full range of absolute magnitudes in CfA survey • integrated optical spectra

  10. Infrared Assumptions: young stars dominate emission large optical depth continuous burst model Salpeter IMF Measuring Star Formation Rates SFRIR = 4.5 x 10-44 x LIR e.g., Kennicutt (1998) NASA/JPL-Caltech/S. Willner (CfA)

  11. Optical : Ha Assumptions: no dust total re-emission of ionizing photons Salpeter IMF Measuring Star Formation Rates SFRHa = 7.9 x 10-42 x LHa e.g., Kennicutt (1998) Image credit: Fabio Bresolin (U. Hawaii)

  12. Ha vs. Infrared SFRs Kewley et al. (2002, AJ, 124, 3135) SFR(IR) SFR(Ha)

  13. Star Formation Rate Discrepancies Teplitz et al. (2003) filled = [OII] unfilled = Ha

  14. [OII] SFR SFR([OII]) = (1.4 +/- 0.4) x 10-41 x L([OII]) (Kennicutt 1998, 1992) Key Assumptions: Observed [OII]/Ha = 0.6 Observed [NII]/Ha = 0.5 (blended) No effect from ionization state of gas Independent of metallicity Salpeter IMF

  15. 100 rms = 0.11 1.0 Kewley, Geller, & Jansen (2004, AJ, 127, 2002) 0.01 0.01 1.0 100 SFR (Ha) 0.4 [OII] & Ha SFRs ratio -0.4 SFR [OII]

  16. [OII] SFR SFR([OII]) = (1.4 +/- 0.4) x 10-41 x L([OII]) (Kennicutt 1998, 1992) Key Assumptions: Observed [OII]/Ha = 0.6 Observed [NII]/Ha = 0.5 (blended) No effect from ionization state of gas Independent of metallicity Salpeter IMF

  17. Ionizing Radiation Field Starburst99 (Leitherer et al. 1999, Crowther et al. 2006) Instantaneous & Continuous Burst Models Extended Wolf-Rayet Atmospheres

  18. Photoionization Models Kewley et al. (2001) Mappings III- radiative transfer including dust Sutherland & Dopita 1993, Groves et al. 2003, 2006 Metallicity:0.05, 0.2, 0.4, 1.0, 2.0 x solar Ionization Parameter:1e7, 2e7, 4e7, 8e7, 1.5e8, 3e8 cm/s alternative: CLOUDY (Ferland et al. 1998)

  19. O ( ) log +12 H H ionizing photons/Area/s SH q = nH Ionization parameter: (cm/s) hydrogen density Definitions Metallicity = Gas-phase Oxygen Abundance = Solar ~ 8.7 (Allende Prieto et al. 2001)

  20. New [OII] calibration: Theoretical

  21. New [OII] calibration: Theoretical kHa L([OII]) SFR([OII],Z) = a+ bZ - cZ2 + dZ3 where Z = metallicity = log(O/H)+12 • Includes Metallicity & Ionization Parameter Correction Kewley, Geller, & Jansen (2004, AJ, 127, 2002)

  22. New [OII] calibration: Theoretical rms=0.04-0.05 (c.f. 0.11)

  23. Metallicity at High-z • Lilly, Carollo & Stockton 2003: M91 • 0.5 < z < 1.0 : log(O/H)+12~8.9 (c.f. 8.6 locally) • Hippelein et al. (2003): • 0.25 < z < 1.2 : [OII]/Ha = 0.9 (intrinsic) our [OII]/Ha - metallicity calibration • log(O/H)+12~8.77 Teplitz et al. (2003): • 0.4 < z < 1.4 : [OII]/Ha = 0.45 (observed) • = 0.83 (intrinsic) our [OII]/Ha - metallicity calibration • log(O/H)+12~8.81 Luminosity Selection Effect

  24. High-z Galaxies 0.8 < z < 1.6 Hicks et al. (2002) 0.5 < z < 1.1 Tresse et al. (2002)

  25. Star Formation History K98 [OII] SFR inconsistent reddening correction filled = [OII] unfilled = Ha data from Teplitz et al. (2003) Our [OII] SFR log(O/H)+12~8.6, consistent reddening correction also: Rosa-Gonzalez, Terlevich, & Terlevich (2002) Our [OII] SFR log(O/H)+12~8.8 consistent reddening and metallicity correction Kewley, Geller, & Jansen (2004)

  26. Metallicity History Metallicity history of star-forming galaxies still largely theoretical. Nagamine et al. (2001)

  27. Metallicity History Galactic Winds Image credit: FOCAS, Subaru 8.2-m Telescope, NAOJ.

  28. TheoreticalMetallicity History Predicted for: • Star-forming gas • Stars • Neutral gas e.g., Dave & Oppenheimer (2007)

  29. TheoreticalMetallicity History Predicted for: • Star-forming gas • Stars • Neutral gas e.g., Dave & Oppenheimer (2007)

  30. Metallicity Diagnostics “R23” Kewley & Dopita (2002, ApJS, 142, 35) Also: Pagel (1979), McCall et al. (1985), ..., Skillman et al. (1989), McGaugh (1991),..., Zaritsky et al. (1994), Charlot (2001), ...

  31. Metallicity Diagnostics - [NII]/Ha Kewley & Dopita (2002) also: Denicolo, Terlevich & Terlevich (2002) Pettini & Pagel (2004) R23 and [NII]/Ha re-parameterized Kobulnicky & Kewley (2004)

  32. H ionizing photons/Area/s SH q = nH (cm/s) hydrogen density Ionization Parameter - O32 Kewley & Dopita (2002)

  33. Local Samples: NFGS + SDSS Kewley, Jansen & Geller (2005) • 45,086 SDSS • star-forming galaxies • g-band covering • fraction > 20%

  34. GOODS+ : 0.3 < z< 1 ~450 galaxies from: GOODS + Lilly et al. (2003) Kobulnicky et al. (2003) Maier et al. (2004,05,06) Liang et al. (2004) Lamareille et al. (2005) Savaglio et al. (2005)

  35. GOODS+ : 0.3 < z< 1 ~450 galaxies from: GOODS + Lilly et al. (2003) Kobulnicky et al. (2003) Maier et al. (2004,05,06) Liang et al. (2004) Lamareille et al. (2005) Savaglio et al. (2005)

  36. High-z sample • 5 galaxies: 1<z<1.5 (Shapley et al. 2005) • [OII], [OIII], Hb, [NII] • 7 galaxies: 2 < z < 2.5 (Shapley et al. 2004) • [NII], Ha • 2 galaxies: z=2.3, 2.9 (Kobulnicky & Koo 2000) • [OII], [OIII], Hb • 5 galaxies: 2.7<z<3.4 (Pettini et al. 2001) • [OII], [OIII], Hb

  37. Metallicity Diagnostic Discrepancies Kewley & Ellison (2007) SDSS mass-metallicity relation Tremonti et al. (2004)

  38. Metallicity Diagnostic Discrepancies Kewley & Ellison (2007)

  39. Metallicity Diagnostic Discrepancies Before: After: Kewley & Ellison (2007)

  40. Metallicity History 0<z<3 NFGS Lyman Break Galaxies SDSS 0.15 dex/z GOODS+ assumes upper branch Kewley & Kobulnicky (2006, in prep)

  41. Metallicity History 0<z<3 Models: Dave & Oppenheimer (2006) Kewley & Kobulnicky (2006, in prep)

  42. Metallicity History Bias: 0.4 < z < 1 Assumptions: R23 upper branch AV = 1 Kewley & Kobulnicky (2006, in prep)

  43. Solution: 0.4 < z < 1 NIR multi-object spectroscopy Subaru - MOIRCS observations ongoing Soon to come: VLT - NIRMOS (2008/2009) Gemini-S - Flamingos-II (2008) Magellan - MMIRS (2008)

  44. Metallicity History Bias: z > 1 Color selection BzK Lyman Break

  45. High-z Metallicity Bias? Try alternative selection: • Lensed galaxies • GRB Hosts • [OII], [OIII] emitters • Luminous red star-forming galaxies

  46. Alternative selection: Lensed Galaxies Lemoine-Busserolle et al. (2003) z=1.9 log(O/H)+12 ~ 7.6 +/- 0.2 log(O/H)+12 ~ 9.0 +/- 0.1

  47. Metallicity History 0<z<3 Models: Dave & Oppenheimer (2006) Kewley & Kobulnicky (2006, in prep)

  48. Alternative selection: GRB Hosts Local GRB hosts may favor low metallicity galaxies GRB Hosts Kewley et al. (2006)

  49. SFR Conclusions • Agreement between SFRIR and SFRHa • Discrepancy between SFR[OII] and SFRHa: • reddening and metallicity • New theoretical SFR[OII] calibration removes • this discrepancy • ... but what if metallicity changes with redshift?

  50. Metallicity Conclusions • Metallicity History for star-forming galaxies • Metallicity evolution observed • First comparison with appropriate metallicities • from cosmological hydrodynamic simulations • Steeper Metallicity evolution predicted • More work needed for robust metallicity history...