Piece of Narval spectrum of HD 94766 in the B band where two lines of O₂ showing shoulders and a self-reversal. The black line with dots is the original spectrum (right scale), the green line with dots is the corrected spectrum after division by the convoluted transmittance. The red line is the TAPAS transmittance convoluted to a resolution of 66 000. The transmittance at high resolution is also plotted (blue), showing that both lines are saturated at the center, and the exact value of the 4 central spectels of the corrected spectrum is somewhat meaningless. There are no H₂O absorption features in this range.