We constructed a local luminosity function ( LF ) of galaxies using a flux-limited sample ( S _ { 170 } \geq 0.195 ~ { } \mbox { Jy } ) of 55 galaxies at z < 0.3 taken from the ISO FIRBACK survey at 170 \mu m. The overall shape of the 170- \mu m LF is found to be different from that of the total 60- \mu m LF ( Takeuchi , Yoshikawa , & Ishii 2003 ) : the bright end of the LF declines more steeply than that of the 60- \mu m LF .
This behavior is quantitatively similar to the LF of the cool subsample of the IRAS PSC z galaxies .
We also estimated the strength of the evolution of the LF by assuming the pure luminosity evolution ( PLE ) : L ( z ) \propto ( 1 + z ) ^ { Q } .
We obtained Q = 5.0 ^ { +2.5 } _ { -0.5 } which is similar to the value obtained by recent Spitzer observations , in spite of the limited sample size .
Then , integrating over the 170- \mu m LF , we obtained the local luminosity density at 170 \mu m , \rho _ { L } ( 170 \mu \mbox { m } ) .
A direct integration of the LF gives \rho _ { L } ( 170 \mu \mbox { m } ) = 1.1 \times 10 ^ { 8 } h L _ { \odot } \mbox { Mpc } ^ { -3 } , whilst if we assume a strong PLE with Q = 5 , the value is 5.2 \times 10 ^ { 7 } h L _ { \odot } \mbox { Mpc } ^ { -3 } .
This is a considerable contribution to the local FIR luminosity density .
By summing up with other available infrared data , we obtained the total dust luminosity density in the Local Universe , \rho _ { L } ( \mbox { dust } ) = 1.1 \times 10 ^ { 8 } h L _ { \odot } \mbox { Mpc } ^ { -3 } .
Using this value , we estimated the cosmic star formation rate ( SFR ) density hidden by dust in the Local Universe .
We obtained \rho _ { SFR } ( \mbox { dust } ) \simeq 1.1 \mbox { - - } 1.2 h \times 10 ^ { -2 } M _ { \odot } % \mbox { yr } ^ { -1 } \mbox { Mpc } ^ { -3 } , which means that 58.5 % of the star formation is obscured by dust in the Local Universe .
ust , extinction — galaxies : evolution — galaxy formation — galaxies : luminosity function , mass function — infrared : galaxies