NGC 2264 molecular cloud: Ammonia and OH observations

Journal Article · Sun Jun 15 04:00:00 EDT 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158048· OSTI ID:5002961

Lang, K R; Willson, R F

Line emission from OH and HN/sub 3/ has been mapped in the region of the young star cluster NGC 2264. The NH/sub 3/ emission has been resolved into two components which are joined by a major axis lying along the galactic plane. A systematic velocity gradient of 3 km s/sup -1/ has been measured across the 2 pc extent of the NH/sub 3/ emission, and this gradient is interpreted in terms of a ''rotation'' of the two components about a minor axis centered midway between them and inclined at 90/sup 0/ to the galactic plane. The inferred rotation period of 4 million years corresponds to a Keplerian mass of approx.10/sup 3/ M/sub sun/. The NH/sub 3/ emission suggests an embryonic binary star system whose angular momentum could have been derived from the gravitational collapse of a differentially rotating interstellar cloud with a size of approx.10 pc, a molecular hydrogen number density of approx.5 cm/sup -3/, a temperature of approx.10 K, and a Jeans mass of approx.10/sup 3/ M/sub sun/. Because the OH emission is excited in the more tenuous parts of the region, it is more extensive and has a center shifted away from one of the NH/sub 3/ components in a direction where shearing motions may exist.

• Research Organization: Department of Physics, Tufts University
• OSTI ID: 5002961
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 238:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102 -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMMONIA
BINARY STARS
CHEMISTRY
COSMOCHEMISTRY
EMISSION SPECTRA
ENERGY-LEVEL TRANSITIONS
HYDRIDES
HYDROGEN COMPOUNDS
HYDROXYL RADICALS
INTERSTELLAR SPACE
MOLECULES
MOTION
NEBULAE
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
RADIAL VELOCITY
RADICALS
ROTATION
SPACE
SPECTRA
STAR ACCRETION
STAR CLUSTERS
STAR EVOLUTION
STARS
VELOCITY