Astron. Astrophys. Suppl. Ser. 130, 449-454

The thicknesses and inclinations of 71 northern spiral galaxies

Jun Ma^1,2,3 - Qiu-He Peng¹ - Qiu-Sheng Gu^1,2

Send offprint request: Jun Ma, e-mail: qhpeng@nju.edu.cn

1 - Department of Astronomy, Nanjing University, Nanjing, 210093, China
2 - United Lab. for Optical Astronomy, The Chinese Academy of Sciences, China
3 - Shanghai Astronomical Observatory, the Chinese Academy of Sciences, Shanghai 200030, China

Received September 23, 1997; accepted January 5, 1998

Abstract:

This paper presents the thicknesses and inclinations (i.e., the angle between the galactic plane and the tangent plane) of 71 northern spiral galaxies. The method for measuring the thickness has been proposed by Peng. It is based on the solution of Poisson's equation for a logarithmic disturbance of density. The inclination is determined by assuming that the pattern of spiral structure is a logarithmic spiral. We find that the thickness is correlated with color and with the ${\rm H}_{\alpha}+{\rm [NII]}$ equivalent width.

Key words: galaxies: spiral; structure; kinematics and dynamics; fundamental parameters