1. Lisa Kewley - kewley@ifa.hawaii.edu Lisa Kewley (IfA, U.Hawaii) Collaborators: C. Kobulnicky (U.Wyoming), M. Geller (SAO), B. Barton (UC Irvine), R. Jansen (ASU) B. Barton (UC Irvine), R. Jansen (ASU)

2. Lisa Kewley - kewley@ifa.hawaii.edu Motivation Motivation Metallicity diagnostics Metallicity diagnostics Local samples: Local samples: NFGS Galaxy Pairs Intermediate-z: GOODS Intermediate-z: GOODS Metallicity History 0<z<1 Metallicity History 0<z<1 Future Directions Future Directions Summary

3. Lisa Kewley - kewley@ifa.hawaii.edu Motivation 1. Metallicity history of star-forming galaxies still largely theoretical. Nagamine et al. (2001)

4. Lisa Kewley - kewley@ifa.hawaii.edu data from Teplitz et al. (2003) filled = [OII] unfilled = H  K98 [OII] SFR Our [OII] SFR log(O/H)+12~8.6 A V =1 also: Rosa-Gonzalez, Terlevich, & Terlevich (2002) Our [OII] SFR log(O/H)+12~8.8 A V =1 Motivation 2. [OII] SF History Kewley, Geller & Jansen (2004)

5. Lisa Kewley - kewley@ifa.hawaii.edu Kewley & Dopita (2002, ApJS, 142, 35) Metallicity Diagnostics “R 23 ”

6. Lisa Kewley - kewley@ifa.hawaii.edu Metallicity Diagnostics - [NII]/H  Kewley & Dopita (2002, ApJS, 142, 35) also: Denicolo, Terlevich & Terlevich (2002, MNRAS, 330, 69) R 23 and [NII]/H  re-parameterized Kobulnicky & Kewley (2004,ApJ, 617, 240)

7. Lisa Kewley - kewley@ifa.hawaii.edu Local Sample: NFGS 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 See Jansen et al. (2000) http://cfa-www.harvard.edu/~jansen/nfgs/nfgssample.html

8. Lisa Kewley - kewley@ifa.hawaii.edu Local Sample: Galaxy Pairs 502 galaxies objectively selected from the CfA redshift catalog (v < 2300 km/s,  v < 1035 km/s,  D < 77 h -1 Mpc) Nuclear spectra for ~200 galaxies in pairs (Barton et al. 2000) EWs + stellar population synthesis “burst timescale’’ (Barton et al. 2003)

9. Lisa Kewley - kewley@ifa.hawaii.edu NFGS & Galaxy Pairs Pairs NFGS Nuclear Spectra: Requires Aperture Correction

10. Lisa Kewley - kewley@ifa.hawaii.edu Aperture Correction Correction ~ 0.13 dex but may vary between 0-0.4 dex Kewley, Geller, & Jansen 2005, PASP, 117, 227

11. Lisa Kewley - kewley@ifa.hawaii.edu GOODS Survey: 0.3 < z< 1 204 galaxies with metallicity-quality spectra 204 galaxies with metallicity-quality spectra Metallicities calculated using EWs Metallicities calculated using EWs Upper R 23 branch assumed Upper R 23 branch assumed A v =1 assumed if no H  A v =1 assumed if no H  See Kobulnicky & Kewley (2004, ApJ, 617, 240)

12. Lisa Kewley - kewley@ifa.hawaii.edu GOODS Survey: 0.3 < z< 1 Kobulnicky & Kewley (2004, ApJ, 617, 240)

13. Lisa Kewley - kewley@ifa.hawaii.edu GOODS Survey: 0.3 < z< 1 Kobulnicky & Kewley (2004, ApJ, 617,240)

14. Lisa Kewley - kewley@ifa.hawaii.edu Conclusions Galaxy pairs nuclei span larger metallicity range Galaxy pairs nuclei span larger metallicity range than NFGS: than NFGS: less enriched - dynamical mixing? less enriched - dynamical mixing? Preliminary Metallicity History Preliminary Metallicity History (for star-forming galaxies) (for star-forming galaxies) Metallicity evolution observed.... Metallicity evolution observed.... but more work to do... but more work to do...

15. Lisa Kewley - kewley@ifa.hawaii.edu Pairs GOODS assumes upper branch LBGs: Pettini et al. (2001) Shapley et al. (2004) Kobulnicky & Koo (2000) Future Directions: 0<z<3

16. Lisa Kewley - kewley@ifa.hawaii.edu Future Directions Near-IR Spectra (R 23 degeneracy, A v ) Near-IR Spectra (R 23 degeneracy, A v ) Modelling of emission-line selection effects Modelling of emission-line selection effects More galaxies! More galaxies!