2019AstBu..74..277K

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 > 60000. 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 in the atmosphere confirming the status of a post-AGB star for V1648 Aql.