Large-scale fragmentation of gas cloud rotating at the Galactic center

Abstract

A rotating and slowly-contracting gas cloud is followed in the deep gravitational potential of the galactic center. When the gas density increases as high as (102 — 103)H2 cm—3, which is more than twenty times as large as the background matter density, the self-gravity of the cloud becomes dominant to govern its dynamical structure. The cloud elongates and then splits into two separated objects, as observed at the centers of IC342, NGC6946, and Maffei 2 where we have two symmetric peaks on the major axis of the 12CO (J=1-0) cloud.