IceCube Neutrino Observatory receives major upgrade beneath Antarctic ice

After three South Pole field seasons, IceCube completed its first major upgrade in 15 years, installing more sensitive light sensors and calibration devices deep in Antarctic ice to improve neutrino measurements.

IceCube at the South Pole has completed its first major upgrade since the detector began operating 15 years ago. The work took place over three consecutive field seasons and finished in the most recent season. Teams installed new, higher-performance light sensors and calibration equipment deep in the Antarctic ice. The project is led by the University of Wisconsin–Madison with primary support from the U.S. National Science Foundation. Key details: - Two new types of light sensors were deployed; they offer about two to three times the sensitivity of the original sensors. - Crews drilled six holes roughly a mile and a half deep using a 5-megawatt hot water drill, with each hole taking around three days to complete. - Engineers and scientists from the U.S., Sweden, Thailand, New Zealand, Taiwan, Germany, Australia and Japan worked with Antarctic support contractors to complete the installation. - Drilling equipment was fabricated at UW–Madison’s Physical Sciences Laboratory. - The team also installed two seismometers described as the deepest in the world and collected water samples for microbiology studies. - The upgrade enables improved characterization of the surrounding ice and a reanalysis of 15 years of archived data. Summary: The new sensors and calibration devices are intended to improve reconstruction of neutrino events, enhance measurements related to cosmic rays and galactic supernovae, and allow scientists to revisit archived observations with better precision. Commissioning will continue to verify the functionality of the newly deployed systems, and the upgrade is described as a stepping-stone toward a proposed IceCube-Gen2 expansion.