On the possibility of observing H2 emission from primordial molecular cloud kernels
On the possibility of observing H2 emission from primordial molecular cloud kernels
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关于观测原始分子云内核 H2 发射的可能性
DOI：
10.1046/j.1365-8711.2002.05301.x
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发表时间：
2001
影响因子：
4.8
通讯作者：
J. Silk
中科院分区：
文献类型：
--
作者：
H. Kamaya;J. Silk
我们研究了在原始分子云内核组装过程中观测氢气排放的前景。根据最近的数值模拟，原始分子云核心与当前时代的分子云核心相似，可以在 1þ z , 20 左右出现。内核在内核内部形成，第一批恒星将出现在内核内部。内核通常收缩形成第一代恒星之一，其吸积率高达 ,0.01 M( yr。这是由于原始丰度而发生的，导致内核温度达到 1000 K 量级，并且塌缩的内核以 ,10 erg s 的速率发射 H2 线辐射。主要是 J 1⁄4 5 2 3 ðv 1⁄4 0Þ 旋转发射在红移 1þ z , 20 处，单个内核的预期通量为 0.01mJy，虽然在不久的将来任何可用的设施都无法观测到单个物体，但在银河系尺度上预期的原始星团聚集可能会导致亚 mJy 级别的通量，我们还检查了旋转 J 1⁄4 2 2。 0 ðv 1⁄4 0Þ 和振动 dv 1⁄4 1 发射线可以检测到前者。
We study the prospects for observing H2 emission during the assembly of primordial molecular cloud kernels. The primordial molecular cloud cores, which resemble those at the present epoch, can emerge around 1þ z , 20 according to recent numerical simulations. The kernels form inside the cores, and the first stars will appear inside the kernels. A kernel typically contracts to form one of the first generation stars with an accretion rate that is as large as ,0.01 M( yr. This occurs owing to the primordial abundances, which result in a kernel temperature of order 1000 K, and the collapsing kernel emits H2 line radiation at a rate ,10 erg s. Predominantly J 1⁄4 5 2 3 ðv 1⁄4 0Þ rotational emission of H2 is expected. At redshift 1þ z , 20, the expected flux is ,0.01mJy for a single kernel. While an individual object is not observable by any facilities available in the near future, the expected assembly of primordial star clusters on subgalactic scales can result in fluxes at the sub-mJy level. This is marginally observable with ASTRO-F and ALMA. We also examine the rotational J 1⁄4 2 2 0 ðv 1⁄4 0Þ and vibrational dv 1⁄4 1 emission lines. The former may possibly be detectable with