标题： 天鹅环选定区域的紫外、光学和X射线影像比较 显示英文标题

标题： A Comparison of Ultraviolet, Optical, and X-Ray Imagery of Selected Fields in the Cygnus Loop

摘要： 在1990年和1995年的Astro-1和Astro-2航天飞机任务期间，使用紫外成像望远镜（UIT）观测了位于北冕座环状超新星遗迹边缘周围的五个直径为40角分的视场的远紫外（FUV）图像。 这些视场涵盖了广泛的条件，包括各种几何形状和物理尺度下的辐射激波和非辐射激波。 在这些激波中，UIT的B5带主要采样CIV 1550和氢双光子再结合连续谱。HeII 1640和OIII] 1665发射线也有较小的贡献。 我们展示了这些新的FUV图像，并将其与光学Hα和[OIII]以及ROSAT HRI X射线图像进行比较。 通过将UIT图像与其他波段的图像进行对比，可以深入了解这些不同类型发射的空间变化和位置。 通过对特定地点的冲击模型计算和已发表的FUV光谱进行比较，我们推测共振散射在北冕座环强FUV允许线上普遍存在，尤其是在以往大多数研究中通常选择观测的明亮光学细丝中。 显示英文摘要

摘要： During the Astro-1 and Astro-2 Space Shuttle missions in 1990 and 1995, far ultraviolet (FUV) images of five 40' diameter fields around the rim of the Cygnus Loop supernova remnant were observed with the Ultraviolet Imaging Telescope (UIT). These fields sampled a broad range of conditions including both radiative and nonradiative shocks in various geometries and physical scales. In these shocks, the UIT B5 band samples predominantly CIV 1550 and the hydrogen two-photon recombination continuum. Smaller contri- butions are made by emission lines of HeII 1640 and OIII] 1665. We present these new FUV images and compare them with optical Halpha and [OIII], and ROSAT HRI X-ray images. Comparing the UIT images with those from the other bands provides new insights into the spatial variations and locations of these different types of emission. By comparing against shock model calculations and published FUV spectroscopy at select locations, we surmise that resonance scattering in the strong FUV permitted lines is widespread in the Cygnus Loop, especially in the bright optical filaments typically selected for observation in most previous studies.