Tercero B, Cernicharo J, Cuadrado S, de Vicente P, Guélin M
Observatorio Astronómico Nacional (OAN-IGN). Calle Alfonso XII, 3, E-28014 Madrid, Spain.
Observatorio de Yebes (IGN). Cerro de la Palera s/n, E-19141 Yebes, Guadalajara, Spain.
Astron Astrophys. 2020 Apr 24;636. doi: 10.1051/0004-6361/202037837. eCollection 2020 Apr.
We present the first detections of CHSH, CH, CN, HCOOH, CHCHCN, and HCN in an extragalactic source. Namely the spiral arm of a galaxy located at z = 0.89 on the line of sight to the radio-loud quasar PKS 1830-211. OCS, SO, and NHCN were also detected, raising the total number of molecular species identified in that early time galaxy to 54, not counting isotopologues. The detections were made in absorption against the SW quasar image, at 2 kpc from the galaxy centre, over the course of a Q band spectral line survey made with the Yebes 40 m telescope (rest-frame frequencies: 58.7-93.5 GHz). We derived the rotational temperatures and column densities of those species, which are found to be subthermally excited. The molecular abundances, and in particular the large abundances of CH and of several previously reported cations, are characteristic of diffuse or translucent clouds with enhanced UV radiation or strong shocks.
我们首次在一个河外源中探测到了CHSH、CH、CN、HCOOH、CHCHCN和HCN。具体来说，是在射电强类星体PKS 1830 - 211视线方向上，位于红移z = 0.89处的一个星系的旋臂中探测到的。还探测到了OCS、SO和NHCN，使得在那个早期星系中鉴定出的分子种类总数（不计同位素变体）增加到了54种。这些探测是在对类星体西南图像的吸收谱中进行的，距离星系中心2千秒差距，是利用耶贝斯40米望远镜进行的Q波段光谱线巡天过程中完成的（静止帧频率：58.7 - 93.5吉赫兹）。我们推导了这些分子的转动温度和柱密度，发现它们是亚热激发的。分子丰度，特别是CH以及几种先前报道的阳离子的高丰度，是具有增强紫外线辐射或强烈激波的弥漫或半透明云的特征。
