Figure 1

Effective area for ${\nu }_{\mu }$ as a function of the true simulated energy at the Earth’s surface in intervals of the cosine of the true zenith angle, ${\theta }_{\mathrm{t}}$. The angle-averaged effective area is represented by the solid black line. This calculation was based on the final event sample for events satisfying $N_{\mathrm{ch}}\ge 100$.