A New, Deep JVLA Radio Survey of M33
A New, Deep JVLA Radio Survey of M33
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DOI：
10.3847/1538-4365/ab0e89
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发表时间：
2019-03
期刊：
影响因子：
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通讯作者：
R. White;K. Long;R. Becker;W. Blair;D. Helfand;P. Winkler
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文献类型：
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作者：
R. White;K. Long;R. Becker;W. Blair;D. Helfand;P. Winkler
我们用Jansky甚大阵列对局部群星系M33进行了新的1.4 GHz和5 GHz的观测。我们的测量极限灵敏度为20μJy(4σ)，分辨率为5.“9(半高宽)，对应于817kpc时24pC的空间分辨率。使用一种新的多分辨率算法，我们已经创建了2875个源的目录，其中675个具有明确的光谱指数。我们在Tüllmann等人的319个X射线源的位置上探测到了源。钱德拉对M33进行了调查，其中大部分可能是背景星系。与核源M33 X-8重合的射电源似乎是延伸的。除了众多的H II区或H II区复合体的一部分，我们还探测到了Long等人列出的217个光学超新星遗迹(SNR)中的155个。以及Lee&Lee，使其成为迄今为止已知距离内具有多波长覆盖范围的最大残余物样本。在给定直径的射电与X射线光度之比中，残骸显示出很大的色散，这一结果对当前一代SNR中同步辐射演化模型提出了挑战。
We have performed new 1.4 and 5 GHz observations of the Local Group galaxy M33 with the Jansky Very Large Array. Our survey has a limiting sensitivity of 20 μJy (4σ) and a resolution of 5.″9 (FWHM), corresponding to a spatial resolution of 24 pc at 817 kpc. Using a new multiresolution algorithm, we have created a catalog of 2875 sources, including 675 with well-determined spectral indices. We detect sources at the position of 319 of the X-ray sources in the Tüllmann et al. Chandra survey of M33, the majority of which are likely to be background galaxies. The radio source coincident with M33 X-8, the nuclear source, appears to be extended. Along with numerous H ii regions or portions of H ii region complexes, we detect 155 of the 217 optical supernova remnants (SNRs) included in the lists of Long et al. and Lee & Lee, making this by far the largest sample of remnants at known distances with multiwavelength coverage. The remnants show a large dispersion in the ratio of radio to X-ray luminosity at a given diameter, a result that challenges the current generation of models for synchrotron radiation evolution in SNRs.