On the Largescale Structure in the Cepheus / Cassiopeia Region

The authors redetermined the smooth rotation curve of the Galaxy in the range of the galactocentric distance R = 10 - 17 kpc, by making use of available optical data of H II regions. They then applied their rotation curve to H I survey data to deduce the space distribution of H I gas outside the solar circle. In deriving the space density of H I gas n_H as a function of heliocentric distance, the effect of noncircular motion of the Perseus arm has been taken into account. The authors examined the bending of the galactic disk in this direction and derived less steep inclination than previously derived ones.