Ice fishing at AZero, part 2

See part 1. A liquid-nitrogen system at the north end of the AZero building helps cool radio-frequency-power cavities in the AZero north and south caves. The liquid nitrogen flows through cryostats that surround the cavities and leaves as cold gas, which is then vented out of the building. The gas is cold enough compared to the ambient temperature that water vapor in the air condenses on the cold pipe pictured above, freezes and builds up as an ice ball. The nitrogen gas flowing out of the pipe creates and sustains a hole (the ice fish’s mouth) in the ice ball. What causes the “fish head”? Chaos, and a pebble for good measure. Photo: Jamie Santucci, AD