We report a Far Ultraviolet Spectroscopic Explorer satellite observation of the supernova remnant N49 in the Large Magellanic Cloud, covering the 905-1187 A spectral region. A 30″ square aperture was used, resulting in a velocity resolution of ～100 km s~(-1). The purpose of the observation was to examine several bright emission lines expected from earlier work and to demonstrate diffuse source sensitivity by searching for faint lines never seen previously in extragalactic supernova remnant UV spectra. Both goals were accomplished. Strong emission lines of O Ⅵ λλ1031.9, 1037.6 and C Ⅲ λ977.0 were seen, Doppler broadened to ±225 km s~(-1) and with centroids redshifted to 350 km s~(-1), consistent with the LMC. Superposed on the emission lines are absorptions by C m and O Ⅵ λ1031.9 at +260 km s~(-1), which are attributed to warm and hot gas (respectively) in the LMC. The O Ⅵ λ1037.6 line is more severely affected by overlying interstellar and H_2 absorption from both the LMC and our Galaxy. N Ⅲ λ989.8 is not seen, but models indicate that overlying absorption severely attenuates this line. A number of faint lines from hot gas have also been detected, many of which have never been seen in an extragalactic supernova remnant spectrum.
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机译：我们报告了大麦哲伦星云中覆盖了905-1187 A光谱区域的超新星残留N49的远紫外光谱资源管理器卫星观测。使用的是30英寸见方的孔径，其速度分辨率为〜100 km s〜（-1）。观察的目的是检查早期工作中预期的几条明亮的发射线，并通过寻找银河系超新星残余紫外线光谱中以前从未见过的微弱线来证明漫射源灵敏度。两个目标都实现了。观察到强的OⅥλλ1031.9、1037.6和CⅢλ977.0的发射谱线，多普勒展宽至±225 km s〜（-1），质心红移至350 km s〜（-1），与LMC一致。排放线上叠加有C m和OⅥλ1031.9在+260 km s〜（-1）处的吸收，这分别归因于LMC中的热气和热气。 OⅥλ1037.6系受到LMC和银河系中星际和H_2的过度吸收的严重影响。 NⅢλ989.8未见，但模型表明，过度吸收会严重削弱该谱线。还检测到许多来自热气的微弱线，其中许多在银河系超新星残留光谱中从未见过。
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