An H2O Maser Near Sagittarius A East: Evidence for Active Massive Star Formation near the Galactic Center
An H2O Maser Near Sagittarius A East: Evidence for Active Massive Star Formation near the Galactic Center
复制标题
人马座 A 东附近的 H2O 脉泽：银河系中心附近活跃的大质量恒星形成的证据
DOI：
10.1086/309698
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
D. Mehringer
中科院分区：
文献类型：
--
作者：
F. Yusef;D. Mehringer
我们介绍了利用甚大阵列（VLA）在DnC配置下对银河系中心内5'的六个场进行H2O脉泽搜索的结果。四个新的H2O脉泽被探测到，典型的光度为10-7 L☉。其中三个脉波与演化中的恒星有关，另一个与人马座A东H II区有关，该区域被认为是离银河系中心最近的活跃恒星形成区。这个H II区域及其相关的H2O脉泽位于壳型超新星遗迹（SNR）源（Sgr A East）和相邻的+50 km s-1分子云之间的边界。Sgr A East在λ = 20 cm处的射电连续图像表明，Sgr A East超新星爆炸的压力波已经到达H II区，并认为不断扩大的信噪比正在诱导大质量恒星的形成。考虑到这种可能性，弱H2O脉泽，如在W28信噪比和相邻分子云边界发现的1720 MHz OH脉泽，也可以用作由扩大的信噪比和分子云相互作用诱导的大质量恒星形成的探针。
We present the results of an H2O maser search of six fields in the inner 5' of the Galactic center using the Very Large Array (VLA) in its DnC configuration. Four new H2O masers are detected with typical luminosities of order 10-7 L☉. Three of the masers are associated with evolved stars and one with the Sgr A East H II region, which is identified as the closest active star-forming region to the Galactic center. This H II region and its associated H2O maser lie at the boundary between the shell-type supernova remnant (SNR) source (Sgr A East) and an adjacent +50 km s-1 molecular cloud. Evidence that the pressure wave of the Sgr A East supernova explosion has reached the H II region is given by presenting a radio continuum image of Sgr A East at λ = 20 cm, and it is argued that the expanding SNR is inducing high-mass star formation. The possibility is considered that weak H2O masers, like the 1720 MHz OH masers found at the boundary of the W28 SNR and an adjacent molecular cloud, may also be used as a probe of massive star formation induced by the interaction of an expanding SNR and molecular clouds.