UBV starcounts in SA54 and global structure of the Galaxy

Using new UBV star-count data obtained from observations with the Kiso Schmidt telescope centered in Selected Area 54, together with literature data on the 22-h field and the North and South Galactic Pole (NGP and SGP) regions, a Galaxy model is developed which consists of a thin-disk, a thick-disk, and a spheroid component. The constraints on structural parameters of these three components are derived. The scale-length of the thin disk is derived to be H(R) = 3.8 kpc. The structural parameters of the thick disk are H(Z) = 900 pc for the scale height and A(thick) = 0.019 for local normalization relative to thin disk.