Researchers from the South Dakota School of Mines & Technology
were on hand for the groundbreaking ceremony that marks the start of
construction on the Long-Baseline Neutrino Facility (LBNF). The facility
will be home to the international collaboration known as the Deep
Underground Neutrino Experiment (DUNE) which is being built and operated
by a group of roughly 1,000 scientists and engineers from 30 countries.
When complete, LBNF/DUNE will be the largest experiment ever built
in the United States to study the properties of mysterious particles
called neutrinos. Unlocking the mysteries of these particles could help
explain more about how the universe works, and why matter exists at all.
The U.S. Department of Energy’s Fermi National Accelerator
Laboratory, located outside Chicago, will generate a beam of neutrinos
and send them 1,300 kilometers (800 miles) through the earth to the
Sanford Underground Research Facility (SURF), where a four-story-high,
70,000-ton detector will be built beneath the surface to catch those
neutrinos. DUNE will have one detector at Fermilab and one at SURF. The
facility at SURF (Far Detector) will include one detector consisting
(when complete) of four 10 kiloton massive modules.
Scientists will study the interactions of neutrinos in the
detectors, looking to better understand the changes these particles
undergo as they travel across the country in less than the blink of an
eye. Ever since their discovery 61 years ago, neutrinos have proven to
be the most surprising subatomic particle, and the fact that they
oscillate between three different states is one of their biggest
surprises. That discovery began with a solar neutrino experiment led by
physicist Ray Davis in the 1960s, performed in the same underground mine
that now will house LBNF/DUNE. Davis shared the Nobel Prize in physics
in 2002 for this experiment.
DUNE scientists will also look for the differences in behavior
between neutrinos and their antimatter counterparts, antineutrinos,
which could give us clues as to why we live in a matter-dominated
universe – in other words, why we are all here, instead of having been
annihilated just after the Big Bang. DUNE will also watch for neutrinos
produced when a star explodes, which could reveal the formation of
neutron stars and black holes, and will investigate whether protons live
forever or eventually decay, which is closely tied to the development
of a unified theory of energy and matter.
SD Mines researchers and engineers are working on various aspects
of the project including efforts to reduce background radiation and
contamination in the components of the detectors. Without the work to
remove background radiation, the detectors will be adversely affected,
mostly for observing neutrinos from supernova explosions in our galaxy.
Assistant Professor of Physics at SD Mines, Juergen Reichenbacher,
Ph.D., has served as the convener of the radiopurity working group and
also lead the effort to ensure the chemical purity of components in
DUNE. Reichenbacher and his graduate student have developed a full
radiological simulation model for all components of DUNE. In addition,
Reichenbacher has developed a unique detector that can measure small
amounts of alpha radiation in various sized parts. He will also lead the
effort to screen for neutron and gamma radiation at DUNE. Reichenbacher
will next take part in a kick-off meeting for the calibration working
group of DUNE.
Mines researchers are also working on some of the components inside
the giant detector modules located in SURF. Assistant Professor of
Physics at Mines, Luke Corwin, Ph.D, is testing light guides that
capture and funnel light, generated during neutrino interactions,
towards sensors inside the DUNE detectors. Corwin will also be involved
in the study of neutrinos produced in the upper atmosphere by impinging
cosmic rays, once the DUNE detectors at SURF are up and running.
At its peak, construction of LBNF is expected to create almost
2,000 jobs throughout South Dakota, and a similar number of jobs in
Illinois. Institutions in dozens of countries will contribute to the
construction of the DUNE components. The DUNE experiment will attract
students and young scientists from around the world, helping to foster
the next generation of leaders in the field and to maintain the highly
skilled scientific workforce in the United States and worldwide.
The facility will be built over the next ten years. Now that the
first shovel of earth has been moved, crews will begin the construction
to excavate more than 870,000 tons of rock to create the huge
underground caverns for the DUNE detectors. Large DUNE prototype
detectors are under construction at European research center CERN, a
major partner in the project, and the technology refined for those
smaller versions will be tested and scaled up when the massive DUNE
detectors are built.
This research is funded by the U.S. Department of Energy Office of
Science in conjunction with CERN and international partners from 30
countries. DUNE collaborators come from institutions in Armenia, Brazil,
Bulgaria, Canada, Chile, China, Colombia, Czech Republic, Finland,
France, Greece, India, Iran, Italy, Japan, Madagascar, Mexico,
Netherlands, Peru, Poland, Romania, Russia, South Korea, Spain, Sweden,
Switzerland, Turkey, Ukraine, United Kingdom and the United States.