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tokens: to an injected ν τ flux with E 0 = 1 EeV. Normalized cumulative distributions from secondary τ -leptons are shown in Figure 4 for injected neutrinos at angles corresponding to the best-fit reconstructed direction of AAE-141220. Figure 4. Normalized cumulative distributions for Earth-emerging τ -leptons. Colors correspond to the incoming τ -neutrino energy, and the gray band is the 95% containment on the error of the reconstructed shower energy of AAE-141220. We next inject a flux of EeV tau neutrinos and find the spectral shape of the secondary ν τ flux that would be incident on IceCube. As we observed zero coincident events in the time window of 10 3 s around AAE-141220 in the prompt analysis, we calculate the maximum allowed flux normalization (at a 90% confidence level) on the primary flux that would evade this nonobservation. The results are displayed in Figure 5 . Figure 5. Upper limits (90% C.L.) placed by calculating the secondary neutrino flux (purple histogram) from an incident flux of EeV neutrinos assuming constant emission over 10 3 s and comparing to the nonobservation of IceCube events in the prompt analysis described in Section 3.1 for AAE-141220. The flux implied by the ANITA observations (black), represented in this figure as , using information about ANITA’s acceptance (Romero-Wolf et al. 2019 ) overshoots this upper limit (purple arrow) by many orders of magnitude. For comparison, upper limits on the time-integrated muon neutrino flux from the prompt analysis are shown in blue. All fluxes are per flavor . Figure 6. (Top two rows) Sky maps and TS distributions from all three analyses for AAC-150108. For AAE-061228, IceCube was not in a full detector configuration at the time of the event, and thus only the steady and rolling analyses were used to search for neutrino emission. Sky maps and TS distributions for these analyses are displayed in the bottom two rows. Although IceCube’s sensitivity is peaked many orders of magnitude below the reconstructed energies of the AAEs, the limits set on any potential neutrino source that created AAE-141220 are more constraining by several orders of magnitude than the implied flux by the ANITA observations. If one considers constant emission over the entire live time of the IceCube event selection, then the time-integrated flux limit set by the IceCube nonobservation of AAE-141220 becomes around 1 order of magnitude less constraining, as is apparent in the steady limits in Figure 2 . However, for the implied normalization placed by ANITA observations, this value would increase by approximately 2 orders of magnitude due to the limited live time of the ANITA flight. This has the overall effect of increasing the tension between these two normalizations by approximately 1 more order of magnitude than for the 10 3 s follow-up shown in Figure 5 . It is worth noting that the logic for scaling time-integrated limits also applies to AAE-061228, even though we cannot constrain the shorter