News Releases

Mines physicists active in two next-generation dark matter experiments
Release Date Thursday, July 17, 2014
South Dakota School of Mines & Technology physicists will participate in two next-generation underground dark matter experiments, including the Large Underground Xenon (LUX)-Zeplin, or LZ, experiment at the Sanford Underground Research Facility in Lead, South Dakota. This photo shows the LUX tank and photomultiplier tubes that Mines researchers calibrated before the tank was filled and data collection began in 2013. The other new experiment in which the School of Mines will participate is the Super Cryogenic Dark Matter Search (CDMS)-SNOLAB collaboration operated in Ontario, Canada.

Photo credit, Matt Kapust/Sanford Underground Research Facility

RAPID CITY, SD (July 17, 2014) – The South Dakota School of Mines & Technology is an active member in both of the next-generation underground dark matter experiments, which will be moving forward according to recent decisions announced by the Department of Energy and the National Science Foundation.

The Large Underground Xenon (LUX)-Zeplin, or LZ, experiment at the Sanford Underground Research Facility in Lead is among the new projects in the search for elusive dark matter that will be supported by the U.S. agencies.

Incoming SD School of Mines & Technology physics faculty members Richard Schnee, Ph.D., and Juergen Reichenbacher, Ph.D., are active members of the LZ experiment team. Mines astrophysicist Xinhua Bai, Ph.D., has been involved in both the current LUX project and LZ, including serving on the LUX executive board.

Additionally, Schnee is a member of the Super Cryogenic Dark Matter Search (CDMS)-SNOLAB collaboration, the other next-generation underground dark matter experiment to receive backing by the Department of Energy and the National Science Foundation. Schnee is a member of the SuperCDMS executive committee and will also lead radon mitigation efforts for SuperCDMS SNOLAB, an experiment operated in Ontario, Canada.

“I am very excited to be joining what will be one of the strongest dark matter groups in the country at the School of Mines, taking advantage of its unique location for underground physics experiments” at the Sanford laboratory, said Schnee. “The huge increase in sensitivity of these new experiments gives us an excellent chance to learn, finally, what is the stuff that holds our galaxy together.”

Both the LZ and SuperCDMS experiments are searching for a specific type of dark matter called weakly interacting massive particles, also known as WIMPs. The experiments are conducted deep underground to shield them from cosmic rays.

The two experiments are highly complementary. SuperCDMS will be more sensitive if the dark matter has a small mass, as favored by some theories, while LZ will be more sensitive if the dark matter is more massive, as favored by others, Schnee said.

“Now, for the first time it will become a reality to directly hunt for dark matter in the exciting range of many theoretical predictions with the upcoming next-generation of dark matter experiments,” said Reichenbacher.

With the support of the state legislature and the Board of Regents, the School of Mines last year established a Ph.D. program in physics, building upon the bachelor’s and master’s programs that were already at the university. By the start of this new academic year, the School of Mines will have added four physics faculty positions in the Ph.D. program alone over the past two years, most of them focused on experiments in the Sanford underground laboratory in Lead.

The university has 50 undergraduate physics students and 13 graduate students, including 12 in the new doctoral program. The university intends to grow to at least 20 Ph.D. students over the next three years.

“We are very pleased with the strength our new faculty members bring to Mines and to science in the state of South Dakota,” said Heather Wilson, president of the SD School of Mines & Technology. “The experiments that will be done at the Sanford lab over the next decade may well change our understanding of the universe – a very exciting prospect.”

These second-generation dark matter experiments will be at least 10 times more sensitive than the current crop of dark matter detectors.

The SD School of Mines & Technology has already played a significant role in one of the current dark matter experiments, the LUX demonstrator a mile below the earth’s surface at the Sanford laboratory. In that experiment Mines collaborates with 100 researchers from 17 universities worldwide.

The LUX dark matter detector is currently the most sensitive of its kind, 20 times more sensitive than similar detectors. It has recently allowed scientists to exclude a large range of other particle interaction cross sections and to establish a baseline for future dark matter detection.

One of scientists’ goals for LUX was to figure out how to build an even larger detector for the next-generation of dark matter experiments. LZ, the 7-ton version of LUX, will have a factor of 1,000 times more sensitivity.

For LZ, Schnee will lead radon mitigation efforts, including working with Sanford laboratory personnel to build a clean room with the lowest radon levels in North America.

Reichenbacher is involved in the design of a unique radioactive Y-Be calibration source that will enable LZ to search in the highly debated low energy range. He also plans to build at the School of Mines campus a unique device for material cleanliness screening that allows for large detector components used at the nearby Sanford laboratory to be finally tested in a non-destructive way before assembly.

Schnee and Reichenbacher will also operate screening devices at the School of Mines campus that test material samples for emanation of critical radon gas. Additionally, they intend to test how radon gas in the air results in radioactivity on material surfaces.

Bai is also guiding doctoral students Mark Hanhardt and Doug Tiedt who are working on LUX/LZ and other research projects at the Sanford laboratory.

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About SDSM&T

Founded in 1885, the South Dakota School of Mines & Technology is a science and engineering research university located in Rapid City, S.D., offering bachelor’s, master’s and doctoral degrees. The university enrolls 2,640 students from 45 states and 37 countries, with a student-to-faculty ratio of 14:1. The average starting salary for graduates is $62,020 with a 98 percent placement rate. Find us online at www.sdsmt.edu, on Facebook at https://www.facebook.com/sdsmt and on Twitter at https://twitter.com/sdsmt.