摘要 射电连续谱偏振观测是探测银河系星际介质性质的有力工具.中德6 cm银道面偏振巡天使用新疆天文台南山站25 m射电望远镜对银道面银经10°~230°、银纬±5°之间的区域进行了总强度和线偏振的巡测.历时10年,完成了世界上地基射电望远镜观测频率最高的银道面射电连续谱偏振巡天,揭示了银道面在6 cm波段的辐射分布和横向磁场取向.该巡天是国产数据描绘的银河系画卷,其较高的观测频率使得消偏振效应小,能够探测来自银河系更远处的偏振辐射.利用这些数据,巡天团队对银河系超新星遗迹、电离氢区、法拉第屏等多种射电目标的研究取得了系列性结果:先后发现了4颗新的银河系超新星遗迹,其中在2011年发布的两个新超新星遗迹G178.2-4.2和G25.1-2.3是国内学者首次使用国内射电望远镜完成的发现工作;对70多个已知超新星遗迹进行了流量密度、偏振和谱的测量,首次探测到超新星遗迹G16.2-2.7、G69.7+1.0、G84.2-0.8、G85.9-0.6、G205.5+0.5和G206.9+2.3的偏振辐射,新的6 cm波段总强度测量还为确定20个超新星遗迹的谱指数提供了关键数据;完成了对巡天范围内可以准确估计6 cm波段流量密度的401个HII区的统计和测量,补充了国际HII区列表中对于延展HII区的数据缺失.在弥漫辐射偏振探测方面,发现了若干在低频射电偏振观测数据中无法显现的、在总强度辐射上没有对应体的高法拉第旋率结构.巡天数据已经在国际学术界产生重要影响,并一直被用于科学研究. Radio continuum polarization observation is a powerful tool to study the properties of the Galactic interstellar medium. By using the 25-m radio telescope of Xinjiang Astronomical Observatories of Chinese Academy of Sciences the Sino-German6 cm polarization survey of the Galactic plane was carried out by the National Astronomical Observatories of Chinese Academy of Sciences and the Max-Planck-Institute for Radio Astronomy. The observed sky coverage is the Galactic plane in the region from 10° to 230° in the Galactic longitude and within ±5° in the Galactic latitude. The survey is by far at the highest frequency for a Galactic plane polarization survey conducted by a ground-based radio telescope. Through the tenyear efforts by the Chinese and German scientists, the survey revealed the distribution of the total intensity emission and the orientation in the sky plane of the Galactic magnetic fields, which allows us to paint a scroll of the Galaxy with the data obtained with a telescope in China. At such a higher frequency than that of other surveys over the world, the 6 cm observations experience less Faraday rotations, and are thus able to detect the polarized emission from a further distance.based on the survey data, we have obtained a series of results on Galactic supernova remnants(SNRs), HII regions and Faraday screens with high rotation measures. Four new Galactic SNRs have been discovered, among which G178.2-4.2 and G25.1-2.3 published in 2011 are the first discovery of Galactic SNRs by a Chinese radio telescope using the first-hand data. Measurements of flux densities, polarization and spectra were performed for more than 70 known SNRs. The polarized emission is observed, for the first time, for the SNRs G16.2-2.7, G69.7+1.0, G84.2-0.8, G85.9-0.6, G205.5+0.5 and G206.9+2.3. The accurate measurements of the 6 cm flux densities are crucial to determine the spectra of 20 SNRs.Measurements and statistic studies were made for 401 HII regions toward which the flux densities can be precisely estimated. The resu
出处 《科学通报》 EI CAS CSCD 北大核心 2021年第11期1315-1326,共12页 Chinese Science Bulletin
基金 国家自然科学基金(U1831103,11763008,U1631105,11303035,10833003,10821061,10773016,10521001,10473015)资助。
关键词 巡天 偏振 射电连续谱 超新星遗迹 HII区 磁场 surveys polarization radio continuum supernova remnants HII regions magnetic fields
分类号 P14 [天文地球—天体物理]
