L483: Warm Carbon-chain Chemistry Source Harboring Hot Corino Activity
L483: Warm Carbon-chain Chemistry Source Harboring Hot Corino Activity
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DOI：
10.3847/1538-4357/aa6300
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发表时间：
2017-03
期刊：
影响因子：
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通讯作者：
Y. Oya;N. Sakai;Yoshimasa Watanabe;A. Higuchi;T. Hirota;A. L'opez-Sepulcre;T. Sakai;Y. Aikawa
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文献类型：
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作者：
Y. Oya;N. Sakai;Yoshimasa Watanabe;A. Higuchi;T. Hirota;A. L'opez-Sepulcre;T. Sakai;Y. Aikawa
利用阿尔马在1.2 mm波段以亚角秒分辨率观测到0类原恒星L483的各种分子谱线。一个下降旋转包络线跟踪的CS线，而一个非常紧凑的组件与广泛的速度宽度观察CS，SO，HNCO，NH 2CHO，和HCOOCH 3线。虽然这个源被认为是在1000 Au尺度的暖碳链化学（WCCC）候选源，但在原恒星附近检测到了热可丽子的复杂有机分子特征，如NH 2CHO和HCOOCH 3。因此，在L483中可以看到热的可里诺化学和WCCC。虽然这样一个混合的化学字符源已被确认为一个中间源在以前的单碟观测，我们在这里报告的第一个空间分辨检测。一个简单的弹道模型可以粗略地解释这个坠落-旋转包层的运动学结构，其中原恒星质量为0.1-0.2 M，离心障半径（离心半径的一半）为30-200 Au，假设倾角为80°（正面为0°）。在上述分子中观察到的宽线发射最有可能来自离心屏障内的盘组件。因此，在离心屏障周围可以看到剧烈的化学变化。
The Class 0 protostar, L483, has been observed in various molecular lines in the 1.2 mm band at a subarcsecond resolution with ALMA. An infalling–rotating envelope is traced by the CS line, while a very compact component with a broad velocity width is observed for the CS, SO, HNCO, NH2CHO, and HCOOCH3 lines. Although this source is regarded as the warm carbon-chain chemistry (WCCC) candidate source at a 1000 au scale, complex organic molecules characteristic of hot corinos such as NH2CHO and HCOOCH3 are detected in the vicinity of the protostar. Thus, both hot corino chemistry and WCCC are seen in L483. Although such a mixed chemical character source has been recognized as an intermediate source in previous single-dish observations, we here report the first spatially resolved detection. A kinematic structure of the infalling–rotating envelope is roughly explained by a simple ballistic model with a protostellar mass of 0.1–0.2 M ⊙ and a radius of the centrifugal barrier (half of the centrifugal radius) of 30–200 au, assuming an inclination angle of 80° (0° for face-on). The broad-line emission observed in the above molecules most likely comes from the disk component inside the centrifugal barrier. Thus, a drastic chemical change is seen around the centrifugal barrier.