Meet the South Pole’s Dark Matter Detective

Matthew Sedacca in Nautilus:

ScreenHunter_2606 Feb. 23 21.10In the late 1990s, a team of physicists at the Laboratori Nazionali del Gran Sasso in Italy began collecting data for DAMA/LIBRA, an experiment investigating the presence of dark matter particles. The scientists used a scintillation detector to spot the weakly interactive massive particles, known as WIMPs, thought to constitute dark matter. They reported seeing an annual modulation in the number of “hits” that the detector receives. This was a potential sign that the Earth is moving through the galaxy’s supposed halo of dark matter—something that few, if any, researchers could claim.

Reina Maruyama’s job, at a detector buried two-kilometers deep in the South Pole, is to determine whether or not these researchers’ findings are actually valid. Previously, Maruyama worked at the South Pole to detect neutrinos, the smallest known particle. But when it came to detecting dark matter, especially with using detectors buried under glacial ice, she was initially skeptical of the task. In those conditions, she “couldn’t imagine having it run and produce good physics data.”

Contrary to Maruyama’s expectations, the detector’s first run went smoothly. Their most recent paper, published in Physical Review D earlier this year, affirmed the South Pole as a viable location for experiments detecting dark matter. The detector, despite the conditions, kept working. At the moment, however, “DM-Ice17,” as her operation is known, is on hiatus, with the team having relocated to Yangyang, South Korea, to focus on COSINE-100, another dark matter particle detector experiment, and continue the search for the modulation seen in DAMA/LIBRA.

More here.