The peculiar elliptical(EOp) galaxy NGC 4486 and two KOIII comparison stars HR5450, HR6935 were observed spectroscopically using the 74-inch telescope and Image Tube at Mt. Stromlo Observatory. From the Gaussian Broadening Function, broadened spectrum of two comparison stars were computed for the range between wavelength 4800 Å and 5400 Å. Velocity dispersions on the line of sight of M87 were obtained by visual fitting. The fitted velocity dispersion is 450 km/sec at the nucleus, 350 km/sec at r = 12¡È, and 300 km/sec at r = 24¡È. Using the photometric data and the central value of velocity dispersion, we determined the mass of M87. From r1/4 law and the Virial theorem the calculated total mass is 2.1 x 1012Msolar. And M/L radio of M87 is about 30.
Journal of Astronomy and Space Sciences
- Pub Date:
- June 1987