## Some statistical properties of spiral galaxies
^{1} Shanghai Astronomical Observatory, CAS, Shanghai, 200030, P.R. China^{2} Chinese National Astronomical Observatories, CAS, P.R. China^{3} Chinese Academy of Science-Peking University, Join Beijing Astrophysical Center, P.R. China^{4} Joint Lab of Optical Astronomy, CAS, P.R. China^{5} CCAST (World Lab., Beijing, 100080, P.R. China)^{6} Department of Astronomy, Nanjing University, Nanjing, 210093, P.R. China
This paper presents some statistical correlations of 72 northern spiral galaxies. The results show that early-type spirals that are brighter, and thicker, and the axis ratios () of the disk tend to be smaller along the Hubble sequence. We also find that correlates strongly with the galaxy's color, and early-type spirals have larger values of . The inclinations obtained by fitting the pattern of a spiral structure with a logarithmic spiral form are nearly the same as those obtained by using the formulas of Aaronson et al. (1980). Finally, the mean measured pitch angles for the different Hubble sequences in the Third Catalogue of Bright Galaxies by de Vaucouleurs et al. (1991) are derived.
## Contents- 1. Introduction
- 2. Principles of obtaining an inclination and a pitch angle
- 3. Statistical properties
- 4. Conclusions
- Acknowledgements
- References
© European Southern Observatory (ESO) 1999 Online publication: September 24, 1999 |