ANITA anomalous events and axion quark nuggets
Xunyu Liang, Ariel Zhitnitsky
Abstract
The Antarctic Impulse Transient Antenna (ANITA) Collaboration [1--3] has reported two anomalous events with noninverted polarity. These events are hard to explain in terms of conventional cosmic rays (CRs). We explore a new possible explanation for these anomalous events by suggesting that these events can be related to the dark matter (DM) annihilations within the so-called axion quark nugget (AQN) DM model. This model was initially invented for a completely different purpose: to explain the observed similarity between the dark and the visible components in the Universe---i.e., ${\mathrm{\ensuremath{\Omega}}}_{\mathrm{DM}}\ensuremath{\sim}{\mathrm{\ensuremath{\Omega}}}_{\text{visible}}$---without any fitting parameters. We investigate the signal properties of the upward-going AQN events, including the event rate, the pulse duration, and the electric field strength, and find them consistent with the observations. We list several features of the upward-going AQN events distinct from conventional CR air showers. The observations (or nonobservation) of these features may substantiate (or refute) our proposal.