We report new improved photometric redshifts of 1048 galaxies in the Hubble Deep Field ( HDF ) .
A standard \chi ^ { 2 } minimizing method is applied to seven-color UBVIJHK photometry by Fernández-Soto , Lanzetta , & Yahil ( 1999 ) .
We use 187 template SEDs representing a wide variety of morphology and age of observed galaxies based on a population synthesis model by Kodama & Arimoto ( 1997 ) .
We introduce two new recipes .
First , the amount of the internal absorption is changed as a free parameter in the range of E ( B - V ) = 0.0 to 0.5 with an interval of 0.1 .
Second , the absorption due to intergalactic HI clouds is also changed by a factor of 0.5 , 1.0 , and 1.5 around the opacity given by Madau ( 1995 ) .
The total number of template SEDs is thus 187 \times 6 \times 3 = 3 , 366 , except for the redshift grid .
The dispersion \sigma _ { z } of our photometric redshifts with respect to spectroscopic redshifts is \sigma _ { z } = 0.08 and 0.24 for z < 2 and z > 2 , respectively , which are smaller than the corresponding values ( \sigma _ { z } = 0.09 and 0.45 ) by Fernández-Soto et al .
Improvement is significant , especially in z > 2 .
This is due to smaller systematic errors which are largely reduced mainly by including three opacities due to intergalactic HI clouds .
We discuss redshift distribution N ( z ) and cosmic star formation rate based on our new photometric redshifts .