The article drops the ball on reporting effective temperature so the abstract is needed to fill in.
https://arxiv.org/abs/1911.12636
) optical spectrum of the B-type supergiant LS 5112, identified as the optical counterpart of the post-AGB candidate IRAS 18379-1707, is analysed. We report the detailed identifications of the observed absorption and emission features in the wavelength range 3700-9200 A for the first time. The absorption line spectrum has been analysed using non-LTE model atmosphere techniques to determine stellar atmospheric parameters and chemical composition. We estimate Teff=18 000±1000 K, logg=2.25±0.08, ξt=10±4 km/s and vsini=37±6 km/s, and the derived abundances indicate a metal-deficient ([M/H]≈−0.6) post-AGB star. Chemical abundances of eight different elements were obtained. The estimates of the CNO abundances in IRAS 18379-1707 indicate that these elements are overabundant with [(C+N+O)/S]=+0.5±0.2 suggesting that the products of helium burning have been brought to the surface as a result of third dredge-up on the AGB. From the absorption lines, we derived heliocentric radial velocity of Vr=−124.0±0.4 km/s. We have identified permitted emission lines of O I, N I, Na I, S II, Si II, C II, Mg II and Fe III. The nebula forbidden lines of [N I], [O I], [Fe II], [N II], [S II], [Ni II] and [Cr II] have also been identified. The Balmer lines Hα, Hβ and Hγ show P-Cygni behaviour clearly indicating post-AGB mass-loss process in the object with the wind velocity up to 170 km/s.