Speaker
Description
The POEMMA-Balloon with Radio (PBR) mission is an Ultra Long Duration Balloon experiment planned for launch in Spring 2027 from Wanaka, New Zealand. Flying at near-space altitudes for more than 20 days over the Southern Ocean, PBR will provide a unique observational platform for ultra-high-energy particles and will serve as a pathfinder for space-based missions such as the dual satellite Probe of Extreme Multi-Messenger Astrophysics (POEMMA) mission. Observations from near-space altitudes offer significant advantages over ground-based measurements, including increased exposure to ultra-high-energy cosmic rays and sensitivity to horizon-scale particle interactions.
PBR adapts key elements of the POEMMA design to a suborbital platform, enabling the validation of detection techniques, trigger strategies, and operational procedures relevant for future space-based missions. The payload combines wide-field optical instruments with radio detector, allowing measurements of atmospheric fluorescence and radio emission from extensive air showers, and providing a flexible testbed for multi-messenger observations from near space.
The mission targets the observation of very-high-energy cosmic rays by the detection of horizontal high-altitude air showers (HAHAs) above the cosmic-ray knee through combined optical and radio techniques, and the follow-up of astrophysical transient alerts in the search for Very-High-Energy Neutrinos (VHENs). In this context, PBR will act as a demonstrator for suborbital sensitivity to horizon-scale neutrino-induced air showers, enabling quantitative performance studies in a largely unexplored observational regime.
Recent KM3NeT observation of ultra-high-energy neutrinos, which appear in tension with existing IceCube and Pierre Auger limits, provide strong motivation for such measurements. By offering an independent assessment of VHENs sensitivity from near-space altitudes, PBR results can be directly compared and interpreted within global neutrino monitoring frameworks such as Planetary Neutrino Monitoring (PLEnuM).
This contribution presents an overview of the PBR payload and its optical and radio detectors, discusses expected scientific performance, and highlights the mission’s unique capability to advance the detection of VHENs and HAHAs.