Modeling of the magnetic chemically peculiar star HD 188101

We present the study of the He-weak star HD 188101. Using spectral observations obtained with the Main stellar spectrograph (MSS) and the Nasmyth echelle spectrograph (NES) mounted on the BTA SAO RAS and the data from the literature, we determined the fundamental parameters: $T_{\rm eff}=15600 \pm 400$ K, $\log g_{\rm spec} = 3.87 \pm 0.13$, $R = 2.1-3.1$ $R_{\odot}$, $M = 3.8-4.8$ $M_{\odot}$. Chemical abundances were determined by the synthetic spectrum method: under the LTE assumption for He, N, Ti, Fe and without LTE for C, O, Mg, Si. For Si and Fe, overabundance of about 0.6 dex relative to the solar abundance was found. The non-LTE calculations with the stellar Si abundance lead to consistent abundances from lines of Si II and Si III, while the difference between LTE abundances amounts to 0.8 dex.