DARK MATTER;
GALAXIES;
ELLIPTIC AND LENTICULAR;
CD;
FUNDAMENTAL PARAMETERS;
GALAXIES INDIVIDUAL (NGC-3379);
PLANETARY NEBULAE;
GENERAL;
TECHNIQUES;
RADIAL VELOCITIES;
D O I:
10.1086/173092
中图分类号:
P1 [天文学];
学科分类号:
0704 ;
摘要:
We present the results of a radial velocity survey of planetary nebulae (PNs) in the normal elliptical galaxy NGC 3379 performed with the Kitt Peak 4 m telescope and the NESSIE multifiber spectrograph. In two half-nights, we measured 29 PNs with projected galactocentric distances between 0.4 and 3.8 effective radii (1 < R < 10 kpc) with an observational uncertainty of approximately 7 km s-1. These data extend 3 times further into the halo than any previous absorption-line velocity study. The velocity dispersion and photometric profile of the galaxy agrees extremely well with that expected from a constant mass-to-light ratio, isotropic orbit Jaffe model with M/L(B) approximately 7; the best-fitting anisotropic models from a quadratic programming algorithm also give M/L(B) approximately 7. The data are consistent with models that contain no dark matter within 3.5 effective radii of the galaxy's nucleus.