Gravitational collapse in molecular cloud cores around ultracompact H II regions - two candidates

Journal Article · Tue Dec 01 04:00:00 EST 1987 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/185069· OSTI ID:5424759

Keto, E R; Ho, P T.P.; Reid, M J

Observations of NH3(1, 1) obtained with 10-arcsec resolution in the molecular cores surrounding two ultracompact H II regions, W3(OH) and G34.3+0.2, are reported. Both sources show extended emission components with velocity gradients consistent with rotation and absorption components that are redshifted with respect to the emission, suggesting gravitational infall. The velocity structure in both sources, and the density and temperature structure in W3(OH), appear similar to that around the previously observed H II region, G10.6-0.4, which is well modeled by a centrally condensed, and centrally heated, molecular core gravitationally collapsing onto the H II region. It is suggested that velocity and temperature structures similar to those seen in W3(OH), G34.3+0.2, and G10.6-0.4 may be a useful signature of gravitational collapse. 34 references.

• Research Organization: Harvard Univ., Cambridge, MA (USA); Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA)
• OSTI ID: 5424759
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 323; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC GASES
COSMIC RADIO SOURCES
DENSITY
FLUIDS
GASES
GRAVITATIONAL COLLAPSE
H2 REGIONS
INTERSTELLAR SPACE
IONIZED GASES
MOLECULES
NEBULAE
PHYSICAL PROPERTIES
RED SHIFT
SPACE
STAR EVOLUTION