Precessing jets in Sagittarius A: Gas dynamics in the central parsec of the Galaxy

Journal Article · Mon Nov 01 04:00:00 EST 1982 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/160401· OSTI ID:6371022

Brown, R L

We suggest that the asymmetric velocity field and the point-reflection symmetry of the radio continuum brightness distribution of the inner parsec of the galaxy can be understood as complementary manifestations of collimated gaseous outflow along twin opposing beams that emanate from a central object. That object appears to be the compact nonthermal radio source Sgr A*. The data are best reproduced by a model in which material is expelled along the rotation axis of Sgr A* and Sgr A* precesses with a period approx.2300 yr such that the precession axis is inclined approx.49/sup 0/ with respect to the line of sight. On the plane of the sky the jets appear to rotate anticlockwise about an axis having a position angle approx.80/sup 0/ (or an inclination of approx.41/sup 0/ with respect to the rotation axis of the Galaxy). The western jet lies between the Sun and Sgr A* and appears blueshifted; the eastern jet appears redshifted and is on the far side of Sgr A*. The ejection velocity is approx.300 km s/sup -1/ and the mass loss rate is one the order of 10/sup -3/ M/sub sun/ yr/sup -1/.

• Research Organization: National Radio Astronomy Observatory
• OSTI ID: 6371022
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 262:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHARGED PARTICLES
COSMIC GASES
COSMIC RADIO SOURCES
FLUIDS
GALAXIES
GALAXY NUCLEI
GASES
IONS
JETS
MILKY WAY
MOTION
NEON IONS
PRECESSION
RADIAL VELOCITY
ROTATION
VELOCITY