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Ultra-high energy (UHE, E>10^17 eV, extending up to 10^20 eV) cosmic rays (CRs) have been discovered for decades, yet their astrophysical origins and acceleration mechanisms remain unresolved. UHE neutrinos, produced through interactions of UHECRs, offer a complementary and potentially decisive probe. Owing to their electrical neutrality and extremely weak interactions, they can traverse cosmological distances without deflection or significant attenuation, and thus are unique and ideal cosmic messengers for bringing information of the UHE sources and also for testing fundamental physics at the highest energies. However, detecting UHE neutrinos is challenging due to thier low flux and small interaction cross section.

UHECRs and Earth-skimming tau neutrinos can be efficiently detected by coherent radio pulses emitted by air showers generated as they interact with the atmosphere. One unexpected discovery using this technique is the so-called ANITA anomalous events (AAEs), having feature of upward-going UHE air showers but cannot be explained as tau neutrinos, which might be a hint of exotic interaction beyond the Standard Model but requires further verification.

TAROGE-M is a radio antenna array operating at 180-450 MHz on top of 2.7 km-high Mt. Melbourne in Antarctica for detecting UHE air showers in near-horizontal directions. TAROGE-M, first built in 2020 and currently has two stations operating, has successfully detected UHECRs, demonstrating its potential of discovering Earth-skimming tau neutrinos and AAEs for unraveling their mysteries. Its detection concept and advantages, as well as the current status will be summarized in this talk.