CONCLUSIONS

MOST if not ALL galaxies ARE shy...

They flushed when forming the bulk of their stars.

Comparison of star formation indicators:

OII, UV, Ha, radio, MIR, FIR

=> need indicators "not" affected by dust absorption

i.e. IR, radio

Origin of CIRB: mostly star formation

Model (Chary & Elbaz 2001) => CIRB is due to:

25 % ULIGs, 60 % LIGs, 15 % galaxies L<10¹¹ Lsol

~ 70 % already resolved into individual galaxies

detected in the MIR

~ 15 % from sub-mm (S> 2 mJy)

-> with lensing: ~ 71 % (S > 0.5 mJy)

~ 80 % of the CIRB due to galaxies at z < 1.5

(only ~ 30 % at 850 microns)

Cosmic Star Formation History:

bulk of present-day stars formed in dusty starbursts

during the last 9 Gyr, i.e. z < 1.5