We present an optical spectrum of the star V1648 Aql (IRAS19386+0155) obtained at the 6-m SAO RAS telescope with a spectral resolution of R ≥ 60 000. Heliocentric radial velocity was measured from numerous metal absorptions is V_r = 10.18 ± 0.05 km s^-1 (V_LSR = 18.1 km s^-1). We determined the atmospheric, circumstellar, and interstellar components in the profile of the Na I D lines at V_r = 9.2, -3.4, and -12.8 km s^-1 respectively. The averaged over 20 identified DIBs velocity V_r = -12.5 ± 0.2 km s^-1 coincides with the interstellar Na I component. Weak emissions with an intensity of about 10% of the local continuum level were detected in the spectrum; they are identified as low-excitation metal lines. Their central position, V_r = 8.44 ± 0.28 km s^-1, points to the presence of a weak velocity gradient in the upper layers of the stellar atmosphere. Based on the spectroscopic data and taking into account the interstellar and circumstellar reddening, we estimated the star’s luminosity M_V ≈ -5^m and also obtained the lower estimate of distance d ≥ 1.8 kpc. Using the model atmosphere method, we determined the fundamental parameters and chemical abundances in the atmosphere confirming the status of a post-AGB star for V1648 Aql.

中文翻译：

---

遥远OH / IR星V1648 Aql的光谱（IRAS 19386 + 0155）

我们提出的星V1648 AQL在6米SAO RAS望远镜的光谱分辨率获得（IRAS19386 + 0155）的光谱- [R ≥60 000日心径向速度从众多金属吸收测量是V _[R = 10.18±0.05 km s ^-1（V _LSR = 18.1 km s ^-1）。我们确定了Na ID线的剖面中的大气，星际和星际分量分别位于V _r = 9.2，-3.4和-12.8 km s ^-1处。识别出的20个DIB的平均速度V _r = -12.5±0.2 km s ^-1与星际Na I分量重合。在光谱中检测到的弱发射强度约为本地连续谱水平的10％；它们被确定为低激励金属线。它们的中心位置V _r = 8.44±0.28 km s ^-1，表明恒星大气的上层存在弱的速度梯度。根据光谱数据，并考虑到星际和拱变红，我们估计星的光度中号_V ≈-5^米，并且还获得的距离的较低的估计d≥1.8 kpc。使用模型大气方法，我们确定了大气中的基本参数和化学丰度，从而确认了V1648 Aql的AGB后恒星的状态。