CO (<i>J</i>= 2–1) Line Observations of the Galactic Center Molecular Cloud Complex. II Dynamical Structure and Physical Conditions

Abstract

A large-scale 12C16O (J = 2-1) survey of the inner few hundred parsecs of the Galaxy has been conducted using the University of Tokyo-Nobeyama Radio Observatory 60 cm survey telescope. We have taken about 70012C16O (J = 2-1) spectra in the region -25 ≤ l ≤ 25 and |b| ≤ 1° with 0125 grid spacing, covering the entire region of the huge molecular cloud complex in the Galactic center. We refer to the CO (J = 1-0) data taken with the Columbia 1.2 m telescope and calculate the J = 2-1 to J = 1-0 intensity ratio. Velocity channel maps and longitude-velocity maps of CO (J = 2-1) line are presented, with corresponding maps of J = 2-1/J = 1-0 intensity ratio.