Contribution of optical/NIR selected galaxies to the MIR Luminosity Function at z~2

Laurie RigucciniUnder the supervision of Marc Sauvage and Emeric Le

Floc’h

Image: réservoir de gaz froid dans la constellation de la croix du SudCrédits : ESA and the SPIRE & PACS consortia

ContextFrom Rodighiero et al. 2009

- Work on the VVDS-SWIRE and GOODS fields- Bolometric LF derived from the extrapolated total IR luminosities from the best-fit to the observed SEDs of each source- Contribution of LIRGS and ULIRGS : sources defined as objects with 11<log(Lir)<12 and log(Lir)>12 respectively

8/06/10 2COSMOS TeamMeeting 2010

Optical and NIR color-color selection

BzK criterion (Daddi et al. 2004)BM/BX criterion (Adelberger et al. 2004)

8/06/10 3COSMOS TeamMeeting 2010

BzK criterion

Extinction vector

88% of the MIPS sources are selected as BzK (with K<23 in AB magnitude, cf McCracken et al. 2010)

88% of the MIPS sources are selected as BzK (with K<23 in AB magnitude, cf McCracken et al. 2010)

8/06/10 4COSMOS TeamMeeting 2010

BM/BX criterion

U G R

8/06/10 5COSMOS TeamMeeting 2010

BM/BX criterion on the optical catalogue

Optical catalog of Ilbert et al. 2009

Templates with the effect of extinction (0<ext<0.2)

90% of the sources of the optical catalog with 1.5<z<2.8 are selected as BM/BX.

90% of the sources of the optical catalog with 1.5<z<2.8 are selected as BM/BX.

8/06/10 6COSMOS TeamMeeting 2010

R<25.5

50 % of the MIPS sources with 1.5<z<2.8 are missed by the BM/BX criterion50 % of the MIPS sources with 1.5<z<2.8 are missed by the BM/BX criterion

Ext = 0.1Ext = 0.3Ext = 0.5

7

Dust-Obscured Galaxies (Dey et al. 2008) • Selection of galaxies at z~2 with F24μm/FR ≥ 982

8/06/10 8COSMOS TeamMeeting 2010

Extinction

8/06/10 9COSMOS TeamMeeting 2010

Luminosity Function at 8μm rest-frame

TotalBzKBM/BXDey’s selection

Luminosity at 8μm rest-frame obtained from the interpolation between the Chary & Elbaz (2001) librairy and the 24μm data.

Just a reminder: 1012 L8μm ~1013 LIR8/06/10 10COSMOS TeamMeeting 2010

Perspective: Herschel

• COSMOS Pacs: 110 and 160 μm • The composite nature of ULIRGs with extreme

optical/mid-IR colors at z~2-3 8/06/10 11COSMOS TeamMeeting 2010

conclusion

• Two criteria based on optic and NIR:– BzK : well adapted to sources affected by

extinction (selects 88% of our sample)– BM/BX : 50% of the 24μm sources are missed,

important fraction of the LF missed at the bright end.

• Criterion based on optic and MIR (R-[24] color) : select highly obscured galaxies.

8/06/10 12COSMOS TeamMeeting 2010

8/06/10 13COSMOS TeamMeeting 2010

Future work

From Guo and White 2008.

LBGBX

8/06/10 14COSMOS TeamMeeting 2010