The Snowball Chamber is a novel concept for rare event detection based on the controlled use of supercooled liquids. In this detector, purified liquids such as water are held below their freezing point in a metastable state, where localized energy depositions—such as those from nuclear recoils—can trigger rapid, visible crystallization events. This process results in a unique “snowball” signature, which can be used to detect rare interactions such as those potentially induced by dark matter or other forms of ionizing radiation.
Beyond its immediate particle physics applications, the Snowball Chamber also can serve as a platform for studying the dynamics of phase transitions in extreme environments. Supercooled liquids are of particular interest in planetary science and astrobiology, as they may exist beneath the icy surfaces of moons like Europa or Ganymede. Understanding how radiation, pressure, and impurities affect nucleation and freezing in such metastable systems could shed light on the thermal behavior of extraterrestrial oceans—and their potential for harboring life.
In this presentation, we introduce the operating principles of the Snowball Chamber, report on early experimental tests of supercooling stability and nucleation behavior, and discuss future directions. These include both optimization of the detector for rare event searches and the use of the system as a terrestrial analog for radiation-induced crystallization in planetary environments.
This work thus represents a multidisciplinary opportunity at the intersection of particle detection, thermodynamics, and planetary exploration.