Observations and temperature-gradient model (i = 80°) of MWC 300. The upper-left panel shows the observed visibilities and the visibilities of the best-fitting model; lower-left the model-predicted and observed closure phases, upper-right the different lines refer to the SED contributions from different components of our model. Black dots are the observed data. The lower-right panel shows the logarithm of brightness distribution of the model disk. North is up and east to the left. The white point represents the location of the primary star. Our observations were performed along the PA of 66.2° (red line). The green line refers to the possible locations of the secondary companion.