OH production rates of comet 12 P as a function of heliocentric distance. The measurements from different sources are shown with different symbols. Error bars represent 1 σ uncertainties, and triangles indicate upper limits. The solid red line shows the best power-law fit, excluding data from immediately after the outbursts on November 14 and February 29 (marked by dashed gray lines). The dashed red line indicates the curve of the water production rate inferred by the OH curve.