Australia Telescope Compact Array observations for project C3736 semester 2025OCTS

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High-energy neutrinos provide the only unobscured view of cosmic ray acceleration in astrophysical sources, yet their electromagnetic counterparts remain poorly understood. The landmark discovery of TXS 0506+056 as the first confirmed neutrino source demonstrated that coordinated multi-messenger observations can unlock the physics of particle acceleration. This proposal establishes the first systematic radio follow-up program for neutrino sources identified by the newly-launched Einstein Probe mission. Using ATCA's rapid-response capabilities, radio observations will commence within 3 days of Einstein Probe X-ray confirmations, targeting $\\sim$5 IceCube ``gold'' neutrino events annually. The two-epoch observing strategy employs optimized 4cm observations (7uJy/beam sensitivity) for initial detection, followed by comprehensive multi-frequency characterization (2.1--19~GHz) to constrain emission mechanisms. Radio spectral modeling will determine fundamental physical parameters including magnetic field strengths and emission region sizes in neutrino production sites. This pioneering program will deliver the first statistical sample of neutrino-associated radio transients, providing robust constraints on cosmic ray acceleration mechanisms while creating valuable legacy datasets for the global multimessenger astronomy community. Success establishes radio observations as essential for neutrino source characterization.