High-velocity Bipolar Outflow Research Articles

The Large Magellanic Cloud Supersoft X-Ray Binary RX J0513.9-6951

view Abstract Citations (70) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Large Magellanic Cloud Supersoft X-Ray Binary RX J0513.9-6951 Crampton, David ; Hutchings, J. B. ; Cowley, A. P. ; Schmidtke, P. C. ; McGrath, T. K. ; O'Donoghue, D. ; Harrop-Allin, M. K. Abstract A detailed analysis of simultaneous photometric and spectroscopic observations of the optical counterpart of the LMC "supersoft" X-ray source RX J0513.9 - 6951 (identified with HV 5682) is presented. The spectrum is dominated by He II emission lines and H + He II blends; no He I is observed, but several higher ionization emission features, especially O VI (3811, 3834, and 5290 Å), are prominent. Radial velocity measurements suggest a binary period of 0.76 days. If the small velocity amplitude, K ∼ 11 km s-11, is interpreted as orbital motion, this implies that the binary system contains a somewhat evolved star plus a relatively massive compact object, viewed nearly pole-on. No orbital photometric variations were found, although irregular brightness changes of ∼0.3 mag occurred. Unusual emission lines are observed that cannot be identified except as high-velocity (4000 km s-1) bipolar outflows or jets. These outflows are seen in H and He II at the same positive and negative velocities. They were relatively stable for periods of about 5 days, but their velocities appear to have been about 250 km s-1 smaller in 1992 than in 1993 or 1994. Publication: The Astrophysical Journal Pub Date: January 1996 DOI: 10.1086/176653 arXiv: arXiv:astro-ph/9507029 Bibcode: 1996ApJ...456..320C Keywords: ACCRETION; ACCRETION DISKS; STARS: BINARIES: SPECTROSCOPIC; STARS: INDIVIDUAL ALPHANUMERIC: RX J0513.9-6951; X-RAYS: STARS; Astrophysics E-Print: uuencoded compressed postscript, 19 pages including 4 tables. Figures available from authors. Also available at http://www.dao.nrc/DAO/SCIENCE/ . Accepted for publication in ApJ full text sources arXiv | ADS | data products SIMBAD (9) NED (1)

A bipolar outflow of ionized gas in K3-50A: H76 alpha radio recombination line and continuum observations of K3-50

view Abstract Citations (50) References (28) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Bipolar Outflow of Ionized Gas in K3-50A: H76 alpha Radio Recombination Line and Continuum Observations of K3-50 Depree, C. G. ; Goss, W. M. ; Palmer, Patrick ; Rubin, Robert H. Abstract The H II regions near K3-50 (G70.3 + 1.6) have been imaged at high angular resolution (approximately 1 sec .3) in the continuum and the recombination lines H76alpha and He76(sub alpha using the Very Large Array (VLA). The helium line is detected in only the brightest component K3-50A while the hydrogen line is detected in three components (K3-50A, B and C1). K3-50A shows a pronounced velocity gradient of approximately 150 km/sec/pc along its major axis (P.A. = 160 deg); in addition a wide range of line widths are observed, from 20 to 65 km/sec. Kinematics from the line data and the morphology of the continuum emission suggest that the ionized material associated with K3-50A is undergoing a high-velocity bipolar outflow. Publication: The Astrophysical Journal Pub Date: June 1994 DOI: 10.1086/174277 Bibcode: 1994ApJ...428..670D Keywords: Bipolarity; H Ii Regions; H Lines; Helium Atoms; Interstellar Matter; Ionized Gases; Kinematics; Mass Flow; Radio Frequencies; Angular Resolution; Gradients; Jet Flow; Spectral Line Width; Velocity; Very Large Array (Vla); Astrophysics; ISM: H II REGIONS; ISM: JETS AND OUTFLOWS; ISM: KINEMATICS AND DYNAMICS; RADIO LINES: ISM full text sources ADS | data products SIMBAD (12)

The Dynamics of the AG Car Ring Nebula

High spatial (2”) and spectral (7 km s–1) resolution observations of the ring nebula surrounding the LBV star AG Carinae are presented. The data, covering Hα and [NII], were obtained with the UCL echelle spectrograph on the AAT and cover 4 radial slit positions centred on AG Car. The nebular motions are clearly resolved and show that it is a single shell expanding at 70 km s–1 which was ejected from the central star some 7 000 years ago. The data also reveal the presence of a high velocity (~ 83 km s–1) bipolar mass outflow which has distorted the northeastern back edge of the shell.

Polarization of the lambda = 1.3 millimeter continuum radiation from the Kleinmann-Low nebula

Linear polarization was detected in the 1.3 mm continuum emission from the Kleinmann-Low (KL) nebula in Orion. The result is P = (2.6 + or - 0.8) percent and Phi = 40 + or - 8 deg. The polarization is due to thermal emission from magnetically aligned dust grains. The present measurement is of higher spatial resolution than polarization measurements of this source which have been made at far-infrared wavelengths, and the magnetic field direction which is inferred result differs by about 20 deg from that which has been inferred from the far-infrared results. The difference is probably due to structure in the magnetic field lines within the region sampled by the far-infrared observations. The field direction given by the 1.3 mm result is parallel to the axis of the high-velocity bipolar outflow in KL. 33 refs.

The circumstellar water fountains of IRAS 16342-3814 - A very high velocity bipolar outflow

Maser emission from OH and H2O is observed to be present over an exceptionally wide range of velocities in the cold, stellar infrared source IRAS 16342-3814. OH emission at 1612, 1665, and 1667 MHz spans 130 km/s, a range far larger than in any other known OH/IR star. The H2O emission features appear as two widely separated doublets with a full velocity spread of 259 km/s. Several lines of evidence point to the conclusion that IRAS 16342-3814 is an evolved star with a bipolar outflow, related to objects such as OH 231.8 + 4.2 and M1 - 92. The H2O masers are interpreted as streams or clumps of molecular gas forced out the polar axes by, or as part of, a wind from an accretion disk, while the OH masers appear to arise from lower velocity material at intermediate latitudes.

Interaction of the outflow and quiescent gas in Orion - HCO(+) aperture synthesis maps

view Abstract Citations (139) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Interaction of the outflow and quiescent gas in Orion : HCO+ aperture synthesis maps. Vogel, S. N. ; Wright, M. C. H. ; Plambeck, R. L. ; Welch, W. J. Abstract The authors present high-resolution (17arcsec) aperture synthesis maps of HCO+ J = 1-0 emission at 89 GHz in the Orion molecular cloud obtained with the Hat Creek millimeter interferometer. The low spatial frequencies of the brightness distribution, which are not sampled by the interferometer, were derived from single-dish data taken with the Onsala 20 m telescope. The HCO+ maps probe the interaction of an outflow from IRc2 with quiescent gas. Four components, with different distributions, kinematics, and chemistry, can be identfied in the HCO+ maps. (1) The quiescent molecular ridge, which is located just outside the expanding ring, or "doughnut", of gas inferred from SO observations. (2) A compact component centered near IRc2. (3) A high-velocity bipolar outflow. It is argued that IRc2 is the source of the outflow. (4) An extended outflow, which consists largely of ambient gas which has been swept up by the high-velocity outflow. Publication: The Astrophysical Journal Pub Date: August 1984 DOI: 10.1086/162351 Bibcode: 1984ApJ...283..655V Keywords: Astronomical Maps; Cosmic Gases; Formyl Ions; Interstellar Gas; Orion Nebula; Radio Astronomy; Abundance; Gas Flow; Interferometry; Synthetic Apertures; Astrophysics full text sources ADS | data products SIMBAD (1)