AI 中文总结
该研究对50个高质量恒星形成区域的四种含氧复杂有机分子进行统一调查，用均匀转动图方法分析，得出柱密度。发现分子丰度比相关性及行为存在差异，与此前观测比较并通过模型定性分析，为常见含氧化合物提供丰度比约束，表明其行为具分子依赖性。
AI 中文摘要
我们对与6.7GHz甲醇脉泽相关的50个高质量恒星形成区域进行了统一的IRAM-30米观测，分析了四种含氧复杂有机分子（甲醇（CH₃OH）、乙醛（CH₃CHO）、甲酸甲酯（CH₃OCHO）和二甲醚（CH₃OCH₃））。通过均匀转动图方法得出柱密度，必要时用CH₃CN作为代理激发温度参考。在CH₃OH归一化丰度比空间中，CH₃OCHO/CH₃OH和CH₃OCH₃/CH₃OH显示出最强的成对相关性，而涉及CH₃CHO的相关性较弱。未发现与银心距离或束平均H₂柱密度有明显单调趋势。与先前观测比较表明，CH₃OCHO - CH₃OCH₃行为在早期丰度比测量范围内，而CH₃CHO在不同研究间变化较大。用一个代表性升温化学模型仅作定性比较，结果为高质量恒星形成区域中常见含氧化合物提供了均匀的束平均丰度比约束，表明其源到源行为是分子依赖的，而非由单一共同丰度模式完全描述。
英文摘要
We present a uniform IRAM-30\,m survey analysis of four oxygen-bearing complex organic molecules (COMs), methanol (CH$_3$OH), acetaldehyde (CH$_3$CHO), methyl formate (CH$_3$OCHO), and dimethyl ether (CH$_3$OCH$_3$), toward 50 high-mass star-forming regions (HMSFRs) associated with 6.7\,GHz methanol masers. Column densities were derived through a homogeneous rotation-diagram approach, with CH$_3$CN used as a proxy excitation-temperature reference when needed. In CH$_3$OH-normalized abundance-ratio space, CH$_3$OCHO/CH$_3$OH and CH$_3$OCH$_3$/CH$_3$OH show the strongest pairwise correlation, whereas the correlations involving CH$_3$CHO are weaker. No clear monotonic trends are found with Galactocentric distance or beam-averaged H$_2$ column density. Comparison with previous observations places the CH$_3$OCHO--CH$_3$OCH$_3$ behavior within the range of earlier abundance-ratio measurements, while CH$_3$CHO shows larger inter-study variation. A representative warm-up chemical model is used only for qualitative comparison with the observed abundance ranges, which are most closely matched during the decline from the post-desorption abundance peaks in the model. These results provide homogeneous beam-averaged abundance-ratio constraints for common O-bearing COMs in high-mass star-forming regions and show that their source-to-source behavior is molecule-dependent rather than fully described by a single common abundance pattern.
Comments9 pages, 6 figures, 3 tables, accepted for publication in A&A
