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arXiv · astro-ph/9710279

UV Absorption Lines from High-Velocity Gas in the Vela Supernova Remnant: New insights from STIS Echelle Observations of HD72089

E. B. Jenkins·T. M. Tripp·E. L. Fitzpatrick·D. Lindler·A. C. Danks·T. L. Beck·C. W. Bowers·C. L. Joseph·M. E. Kaiser·R. A. Kimble·S. B. Kraemer·R. D. Robinson·J. G. Timothy·J. A. Valenti·B. E. Woodgate
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Abstract

The star HD72089 is located behind the Vela supernova remnant and shows a complex array of high and low velocity interstellar absorption features arising from shocked clouds. A spectrum of this star was recorded over the wavelength range 1196.4 to 1397.2 Angstroms at a resolving power lambda/Delta lambda = 110,000 and signal-to-noise ratio of 32 by STIS on the Hubble Space Telescope. We have identified 7 narrow components of C I and have measured their relative populations in excited fine-structure levels. Broader features at heliocentric velocities ranging from -70 to +130 km/s are seen in C II, N I, O I, Si II, S II and Ni II. In the high-velocity components, the unusually low abundances of N I and O I, relative to S II and Si II, suggest that these elements may be preferentially ionized to higher stages by radiation from hot gas immediately behind the shock fronts.

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E. B. Jenkins, T. M. Tripp, E. L. Fitzpatrick, D. Lindler, A. C. Danks, T. L. Beck, C. W. Bowers, C. L. Joseph, M. E. Kaiser, R. A. Kimble, S. B. Kraemer, R. D. Robinson, J. G. Timothy, J. A. Valenti, B. E. Woodgate. 1997-10-24. UV Absorption Lines from High-Velocity Gas in the Vela Supernova Remnant: New insights from STIS Echelle Observations of HD72089. https://doi.org/10.1086/311114

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