ar X iv : a st ro - p h / 96 09 09 6 v 1 1 4 Se p 19 96 Interpretation of UV Absorption Lines in SN 1006 1
نویسندگان
چکیده
We present a theoretical interpretation of the broad silicon and iron ultraviolet absorption features observed with the Hubble Space Telescope in the spectrum of the Schweizer-Middleditch star behind the remnant of Supernova 1006. These features are caused by supernova ejecta in SN1006. We propose that the redshifted Si II 1260 Å feature consists of both unshocked and shocked Si II. The sharp red edge of the line at 7070 km s indicates the position of the reverse shock, while its Gaussian blue edge reveals shocked Si with a mean velocity of 5050 km s and a dispersion of 1240 km s, implying a reverse shock velocity of 2860 km s. The measured velocities satisfy the energy jump condition for a strong shock, provided that all the shock energy goes into ions, with little or no collisionless heating of electrons. The line profiles of the Si III and Si IV absorption features indicate that they arise mostly from shocked Si. The total 1 Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
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