Galactic Center Molecular Arms, Ring and Expanding Shells. II - Expanding Molecular Shell -
Abstract
Description
We investigate the three-dimensional structure of the so-called ``200-pc expanding molecular ring" in the Galactic Center by analyzing (b, Vlsr) diagrams of the 13CO(J=1-0) line emission from the Bell-Telephone Laboratory survey. We show that the b-v features can be fitted by a spheroidal shell pinched at the equator (dumbbell-shaped shell), which we call the expanding molecular shell (EMS). The radius is about 180 pc and the vertical extent is more than +/-50 pc. The shell is expanding at 160 km/s, and is rotating at 70 km/s. The association of the radio continuum emission indicates that the EMS is a mixture of molecular and ionized hydrogen gases. An extended hot (X-ray) plasma appears to fill the interior of the shell. The estimated molecular mass of the shell is approximately 1.E7 Msun and its kinetic energy 2.E54 ergs.
To appear in PASJ vol.47, No.5, 1995, Plain TeX, Figures on request
To appear in PASJ vol.47, No.5, 1995, Plain TeX, Figures on request