Abstract The discovery of propynal HC CCHO in the interstellar medium (ISM), has been reported in previous investigations, but its detection relied on only a few measured rotational transitions. Therefore, we provide in this work an exhaustive experimental study of its rotational spectra in the microwave, millimeter-wave (mm-wave), and sub-millimeter wave (sub-mm) regions from 6 to 480 GHz. We employed different but complementary spectroscopic techniques in the time and frequency domains. Chirped pulse Fourier transform microwave spectroscopy (CP-FTMW) from 6 to 18 GHz was used to measure and analyze the ground state rotational transitions of the three 13C isotopic species in their natural abundances. The Stark-modulation microwave spectroscopy allowed the identification of rotational spectra in excited vibrational states. The room temperature mm-wave and sub-mm wave spectroscopy made possible the study of the rotational spectra from 82 to 480 GHz in the ground state as well as in the five low-lying excited vibrational states. We have collected more than 2500 newly assigned transitions of propynal and determined very accurate sets of spectroscopic rotational constants for each state. Moreover, we have assigned about 200 rotational lines for the three 13C isotopologues. Reliable line-lists of frequencies are provided for further observations of this molecule in different interstellar regions.

中文翻译：

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星际锥体的实验室旋转研究

摘要 在星际介质 (ISM) 中发现丙炔基 HC CCHO，在先前的研究中已有报道，但其检测仅依赖于少数测量的旋转转变。因此，我们在这项工作中对其在 6 至 480 GHz 的微波、毫米波 (mm-wave) 和亚毫米波 (sub-mm) 区域中的旋转光谱进行了详尽的实验研究。我们在时域和频域中采用了不同但互补的光谱技术。6 至 18 GHz 的啁啾脉冲傅立叶变换微波光谱 (CP-FTMW) 用于测量和分析三种 13C 同位素物种在其天然丰度中的基态旋转跃迁。斯塔克调制微波光谱允许在激发振动状态下识别旋转光谱。室温毫米波和亚毫米波光谱使研究 82 至 480 GHz 基态以及五种低位激发振动态的旋转光谱成为可能。我们收集了超过 2500 个新分配的丙炔跃迁，并为每个状态确定了非常准确的光谱旋转常数集。此外，我们为三个 13C 同位素体分配了大约 200 条旋转线。提供了可靠的频率线表，以便在不同的星际区域进一步观察该分子。我们收集了超过 2500 个新分配的丙炔跃迁，并为每个状态确定了非常准确的光谱旋转常数集。此外，我们为三个 13C 同位素体分配了大约 200 条旋转线。提供了可靠的频率线表，以便在不同的星际区域进一步观察该分子。我们收集了超过 2500 个新分配的丙炔跃迁，并为每个状态确定了非常准确的光谱旋转常数集。此外，我们为三个 13C 同位素体分配了大约 200 条旋转线。提供了可靠的频率线表，以便在不同的星际区域进一步观察该分子。