Rotational Spectrum and First Interstellar Detection of 2-Methoxyethanol Using ALMA Observations of NGC 6334I
arxiv(2024)
摘要
We use both chirped-pulse Fourier transform and frequency modulated
absorption spectroscopy to study the rotational spectrum of 2-methoxyethanol in
several frequency regions ranging from 8.7-500 GHz. The resulting rotational
parameters permitted a search for this molecule in Atacama Large
Millimeter/submillimeter Array (ALMA) observations toward the massive
protocluster NGC 6334I as well as source B of the low-mass protostellar system
IRAS 16293-2422. 25 rotational transitions are observed in the ALMA Band 4 data
toward NGC 6334I, resulting in the first interstellar detection of
2-methoxyethanol. A column density of 1.3_-0.9^+1.4× 10^17
cm^-2 is derived at an excitation temperature of 143_-39^+31 K.
However, molecular signal is not observed in the Band 7 data toward IRAS
16293-2422B and an upper limit column density of 2.5 × 10^15 cm^-2
is determined. Various possible formation pathways–including radical
recombination and insertion reactions–are discussed. We also investigate
physical differences between the two interstellar sources that could result in
the observed abundance variations.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要