1 / 25

Yanchun Liang (NAOC, China) 2005-08, Lijiang

The Luminosity-Metallicity and Mass-Metallicity Relations of 0.4<z<1 Luminous Infrared Galaxies :. ---implication on the mass and metal assembly of galaxies. Yanchun Liang (NAOC, China) 2005-08, Lijiang. Collaboration with Francois Hammer, Hector Flores, Francois Assemat

amara
Télécharger la présentation

Yanchun Liang (NAOC, China) 2005-08, Lijiang

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Luminosity-Metallicityand Mass-Metallicity Relations of 0.4<z<1 Luminous Infrared Galaxies : ---implication on the mass and metal assembly of galaxies Yanchun Liang (NAOC, China) 2005-08, Lijiang

  2. Collaboration with Francois Hammer, Hector Flores, Francois Assemat at Paris-Meudon Observatory; David Elbaz, Delphine Marcillacat Saclay-Service d’Astrophysique; Nicolas Gruel at Florid University; Xianzhong Zhengat MPIE; Licai Deng at NAOC; Catherine J. Cesarsky at ESO.

  3. 240 mm How much star formation was hidden by dust over the history of the universe ? (1) IRAS(z<0.3): detected tens of thousands of galaxies with the FIR radiation luminosities From 106Lsun to ~1013Lsun, but only ~2% of the local bolometric luminosity density is due to the luminous IR galaxies (Soifer et al. 1987, ARA&A, 25, 187; Sanders & Mirabel 1996, ARA&A, 34, 749) (2) COBE(DIRBE) detected a diffuse background at l > 140 mm (3) Surveys at 15,90,170,450,850mm (ISO, SCUBA) • strong evolution (Elbaz et al. 2002, A&A 384, 848)

  4. ISOCAM 15 mm MIR source counts • ISO 15 mm source counts show strong evolution • The comoving density of infrared light due to the luminous galaxies (LIR>1011Lsun) was more than 40 times larger at z~1 than today • The main responsibility: • the luminous Infrared starburst galaxies seen by ISO at z>0.4, • SFRs > 50 Msunyr-1 (Elbaz et al. 1999, A&A Lett., 351, L37) (Elbaz et al. 2002, A&A 384, 848; Elbaz & Cesarsky, 2003, Science, 300, 270; Flores et al. 1999, ApJ 517, 148) (4) Most of ISOCAM (>75%)galaxies are Starbursts, AGN only contribute ~20% (Elbaz et al. 2002 A&A 384 848; Fadda et al. 2002, A&A, 383, 838; Flores et al. 1999; Franceschini et al. 2003, A&A, 403, 501; Liang et al. 2003b, A&A, submitted)

  5. The Spitzer view on the history of dusty star formation at 0<z<1 Evolution of the comoving IR energy density up to z=1 (green-filled region) and the respective contributions from low luminosity galaxies (i.e., LIR<1011Lsun, blue-filled area), ``infrared luminous'' sources (i.e., LIR>1011Lsun, orange-filled region) and ULIRGs (i.e., LIR>1012Lsun, red-filled region). The solid line evolves as (1+z)3.9 and represents the best fit of the total IR luminosity density at 0<z<1. Estimates are translated into an ``IR-equivalent SFR'‘ density given on the right vertical axis, where an absolute additional uncertainty of $\sim$\,0.3\,dex should be added to reflect the dispersion in the conversion between luminosities and SFR. (Le Flo’ch et al. 2005, ApJ, astro-ph/0506462 )

  6. Spectroscopy (VLT/FORS2)follow-upfor a large sample of ISOCAM-selected sources(Extinction, Metallicities,L-Z, Mass-Z) (Liang et al. 2004, A&A, 423, 867)

  7. 1. The ISO-selected sample : 105 in 3 fields Sample • CFRS 3h, • UDSR (Ultra-Deep-Survey-Rosat, Marano field), • UDSF (Ultra-Deep-Survey-Firback, Marano field) (Flores et al. 2004, Elbaz et al. 2004, in preparation ) 2. The Optical Observations using VLT/FORS2 with R600 and I600 spectrograph with a resolution of 5 Å, R=1200 5000 - 9000 Å, slit width 1.2"slit length 10" 3. Redshift identifation 92 zmedian=0.587 (64 with z>0.4) 4. Infrared luminosities Log(LIR/Lsun)med=11.26 ( LIRGs with Log(LIR/Lsun)>11) 5. Emission Line Galaxies (ELG) 85% EL galaxies in the ISO-detected objects , 81% EL galaxies in the total

  8. IR luminosity Log(LIR/Lsun)med =11.26 Similar to Veilleux et al.1995, Kim et al. 1995: 11.34 for BGSs 11.38 for WGSs H0=70 km/s/Mpc 11 12 13 9 10 M=0.3, L=0.7

  9. Examples in UDSF Deblending…

  10. z=0.7094 Log(LIR/Lsun)=11.38

  11. Estimate dust extinction Stellar absorption correction Jacoby et al. (1984) • Using Hb/Hg ratio :A V(Balmer) • Using energy balance between Hbetra and IR:A V(IR)

  12. Diagnostic diagram: Starbursts Most of them (>77%) are HII-region-like galaxies Consistent with other fields:>70% of ISOCAM/15m galaxies, “starbursts”

  13. Oxygen abundances in ISM R23 and calibration from Kobulnicky et al. 1999 12+log(O/H) = 8.35 – 8.93, median 8.67  Luminosity-Metallicity relation (L-Z) & Mass-Metallicity relation (Mass-Z)

  14. L-Z relation: z> 0.4 LIRGs are metal deficient ! z> 0.4 LIRGs are 0.3 dex metal-poor from local disks (at a constant MB): ~ 50% (12+log(O/H) = 8.35 – 8.93, median 8.67) ! They can reach local disks locus assuming an infall time of ~ 1 Gyr (PEGASE2, Fioc and Rocca-Volmerange, 1999,astro-ph/9912179: Mtot=1011Msun, also see Kobulnicky et al. 2003, ApJ, 599, 1006) 03.0035 (Liang et al. 2004, A&A, 423, 867)

  15. Are massive spirals already formed at z~ 1 ? ! Connection between LIRGs and disks (z>0.4) (HST morphologies and color maps) : 40% of LIRGs are large disks (Zheng et al, 2004, A&A) !Lilly et al (1998)large disk sample (rdisk > 4 h50-1 kpc) at 0.5 < z < 1:32 (+/-13)% of them are LIRGs ! LIRGs have large stellar masses: 1.4 1010MO <MK < 2.9 1011MO (see also Franceschini et al. 2003, A&A, 403, 501) ! LIRGs have high SFRs: >50 Msunyr-1 , TSF(M/SFR)=0.1-1 Gyr

  16. SFR-Mass relation (Mass double time scale: 0.1-1 Gyr) Time (Gyr)

  17. The Mass-Metallicity relation of 0.4<z<1 galaxies

  18. 30% to 50% of the mass locked in stars in present day galaxies actually condensed into stars at z<1 (Dickinson et al. 2003; Pozzetti et al. 2003; Drory et al. 2004; Bell 2004) Which kinds of galaxies are mainly responsible for such star formation fraction?

  19. The near-IR K-band luminosity is more directly related to the stellar mass of galaxies since it is less affected by star formation and by dust (Charlot 1998; Bell & de Jong 2000): We compare the MK-metallicity (mass-Z) relations of these intermediate-z galaxies with those of local star-forming galaxies. (Liang, Hammer, Flores 2005, A&A, submitted)

  20. The 3 local sample galaxies to compare: NFGS (Nearby Field Galaxy Survey) by Jansen et al. 2000a,b KISS ( Salzer et al. 2005) SDSS (Tremondi et al. 2004; Bell et al. 2003)

  21. NFGS from Jansen et al. 2000a,b Such z> 0.4 galaxies are 0.3 dexmore metal-poor from local disks (at a given MK): ~ 50%

  22. KISS from Salzer et al. 2005

  23. SDSS Tremonti et al. 2004, Bell et al. 2003; The 7 galaxies at z~2.3 from Shapley et al. 2004

  24. Summary • Spectroscopy follow-up for a ISO-selected sample galaxies with 0.4<z<1 • We study their metallicities on the basic of VLT/ FORS2 spectra, the median oxygen abundance of them is 12+log(O/H)~8.67: ~0.3dex more metal deficient than the local star forming galaxies at the given magnitude or stellar mass • By comparing with the local galaxies (e.g. NFGS, KISS, SDSS) and the high-z (z~2.3) galaxies, we can get a basic understanding on the assembly of the metals of galaxies: ~ 50% of metals of these intermediate-z galaxies was formed since z ~ 1

  25. Thank you!

More Related