Unbiased surveys for dense cloud cores using multi-beam supercondutcing receiver

使用多波束超导接收器对密集云核进行无偏调查

• 批准号: 05402003
• 负责人: FUKUI Yasuo
• 金额: $ 24.58万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05402003/
• 关键词: Radio Astronomy; Star Formation; Millimeter Wave Derectors; Molecular Cloud Cores; Molecular Spectra; 星の形成; 星間分子; ミリ波天文学; 星間物質; Radio Astronomy; Star Formation; Millimeter Wave Derectors; Molecular Cloud Cores; Molecular Spectra; 星の形成; 星間分子; ミリ波天文学; 星間物質

We have carried out a large-scale survey with two 4 meter millimeter-wave telescopes, and obtained about 300,000 spectra of ^<13>CO (J=1-0) emission toward the Cygnus, Cassiopeia, Ophiuchus, Serpens and Taurus regions. The observed area corresponds to 15% of the whole sky, which makes this survey the most extensive one among those made in ^<13>CO.We have identified more than 1,000 ^<13>CO clouds and analyzed the physical paramerers of these clouds. Comparing with the IRAS point sources, we have examined the star formation activity of each cloud and the relationship between the characteristics of newly-born stars and those of clouds. This is the first time to analyze characteristics of clouds based on such a uniform spectral data. As a result, following two points are found :(1) The mass spectrum of clouds is expressed as a power-law with the index-1.7 in the range 100-10,000 M_<<of sun>>.(2) There is a relationship between the luminosity of the most luminous star within each cloud and the mass of the cloud ; i.e., the maximum stellar luminosity increases with the cloud mass.We have also found the following three points through the detailed ^<13>CO observations toward Taurus region ; (1) the basic structure of the Taurus cloud is filamentary, (2) star formation has taken place where the column density reaches its highest and (3) soon after the formation occurs, high-density molecular gas disappears. We have studied the dense regions of clouds in detail by observations of C^<18>O,which is more transparent than ^<13>CO,and found that above relations (2) and (3) are more significant than in ^<13>CO.These results are valuable knowledge in order to understand the star formation within molecular gas.

我们已经对两个4米毫米波望远镜进行了大规模调查，并获得了约300,000个光谱 ^<13> CO（J = 1-0）对Cygnus，Cassiopeia，Cassiopeia，Ophiuchus，Serpens，Serpens和Taurus地区的发射。观察到的区域对应于整个天空的15％，这使得该调查成为 ^<13> Co.co的最广泛的调查，我们已经确定了超过1,000 ^<13> CO云，并分析了这些云的物理参数。与IRA点的来源相比，我们研究了每个云的恒星形成活动以及新生恒星的特征与云的特征之间的关系。这是第一次基于这种均匀的光谱数据来分析云的特征。结果，发现了两个点：（1）云的质谱表示为幂律，索引1.7在100-10,000 m _ <<的范围内。即，随着云质量的增加，最大恒星光度的增加。我们还通过详细的 ^<13> CO观察发现了以下三个点。 （1）金牛座云的基本结构是丝状的，（2）恒星形成发生了，柱密度达到其最高，（3）发生后不久，高密度分子气体消失。我们通过观察到C ^<18> O的观测来详细研究了云的密集区域，该观察比 ^<13> CO更透明，发现上述关系（2）和（3）比 ^<13> CO中更为重要。这些结果是有价值的知识，以了解分子气体内的恒星形成。