论文标题
G107.0+9.0：新的大型光学明亮，无线电和X射线淡淡的银河系超新星残留物
G107.0+9.0: A New Large Optically Bright, Radio and X-Ray Faint Galactic Supernova Remnant in Cepheus
论文作者
论文摘要
银河平面的宽视野H-α图像显示，直径为L = 107.0，B = +9.0的新型超新星残留物（SNR）的直径接近三度。深层和更高的分辨率H-Alpha和[O III] 5007 ANG图像显示，沿着残余的北部，西部和西南的肢体沿着数十个H-Alpha细丝，但很少[O III]明亮的细丝。在H-Alpha Virginia Tech Spectral-Line调查图像中，该星云可很好地检测到，其许多明亮的细丝甚至在数字天空调查图像上都可见。几根细丝的低分散光谱显示，Balmer主导，非辐射丝或更常见的SNR辐射丝，[SI II]/H-α比率高于0.5，与冲击热线发射一致。发射线比表明，冲击速度范围从沿其西肢<70 km/s到沿其西北边界的〜100 km/s不等。尽管在ROSAT图像中未看到相关的X射线发射，但微弱的1420 MHz无线电发射似乎与其西部和北部的四肢相吻合。基于对残留的空间解决的H -α和[O III]排放的分析，我们估计残留的距离在1.5-2.0 kpc左右，暗示物理上很大（DIA。 cm^-3），将大约250-300 pc放在银河平面上方。
Wide-field H-alpha images of the Galactic plane have revealed a new supernova remnant (SNR) nearly three degrees in diameter centred at l = 107.0, b = +9.0. Deep and higher resolution H-alpha and [O III] 5007 Ang images show dozens of H-alpha filaments along the remnant's northern, western, and southwestern limbs, but few [O III] bright filaments. The nebula is well detected in the H-alpha Virginia Tech Spectral-Line Survey images, with many of its brighter filaments even visible on Digital Sky Survey images. Low-dispersion spectra of several filaments show either Balmer dominated, non-radiative filaments or the more common SNR radiative filaments with [S II]/H-alpha ratios above 0.5, consistent with shock-heated line emission. Emission line ratios suggest shock velocities ranging from <70 km/s along its western limb to ~100 km/s along its northwestern boundary. While no associated X-ray emission is seen in ROSAT images, faint 1420 MHz radio emission appears coincident with its western and northern limbs. Based on an analysis of the remnant's spatially resolved H-alpha and [O III] emissions, we estimate the remnant's distance around 1.5 - 2.0 kpc implying a physically large (dia.= 75 - 100 pc) and old (90 - 110 x 10^3 yr) SNR in its post-Sedov radiative phase of evolution expanding into a low density interstellar medium (n = 0.05 - 0.2 cm^-3) and lying some 250 - 300 pc above the Galactic plane.
