Posterior distributions of the gravity-darkened physical parameters based on He I 4026 Å line profile modelling with ZPEKTR using Hamiltonian Monte Carlo inference with STAN (HMC). The mean and the 16th and 84th percentile values for each parameter are shown in the histograms, where the blue curves indicate the joint probability density contours for the correlation between the pairs of parameters. The inclination angle that best matches the data on average is ${21.7°}_{-0.4}^{+0.5}$.