Search for upward-going showers with the Pierre Auger Observatory

Motivated by the ANITA report of pulses compatible with upward-going extensive air showers, we present a recent search for such showers using Pierre Auger Observatory. The dataset, registered fluorescence detector Observatory, is scanned to identify ascending from ground. Consistent exit angles reported first and third flights, focus on shower geometries that are incompatible Standard Model interactions neutrinos in Earth. We effective area Observatory generic as function energy altitude. This can be used constrain predictions based physics beyond upgoing-shower interpretation results. To demonstrate method, calculate limits production rate tau leptons near ground emerging under range angles.