The relation between dark matter halos and the loci of star formation at high redshift is a pressing question in contemporary cosmology .
Matching the abundance of halos to the abundance of infrared ( IR ) galaxies , we explore the link between dark matter halo mass ( M _ { h } ) , stellar mass ( M _ { \star } ) and star-formation rate ( SFR ) up to a redshift of 2 .
Our findings are five-fold .
First , we find a strong evolution of the relation between M _ { \star } and SFR as a function of redshift with an increase of sSFR = SFR / M _ { \star } by a factor \sim 30 between z=0 and z= 2.3 .
Second , we observe a decrease of sSFR with stellar mass .
These results reproduce observed trends at redshift z > 0.3 .
Third , we find that the star formation is most efficient in dark matter halos with M _ { h } \simeq 5 \times 10 ^ { 11 } M _ { \odot } , with hints of an increase of this mass with redshift .
Fourth , we find that SFR / M _ { h } increases by a factor \sim 15 between z = 0 and z = 2.3 .
Finally we find that the SFR density is dominated by halo masses close to \sim 7 \times 10 ^ { 11 } M _ { \odot } at all redshift , with a rapid decrease at lower and higher halo masses .
Despite its simplicity , our novel use of IR observations unveils some characteristic mass-scales governing star formation at high redshift .