Deep Thoughts
Notes from the underground by Communications Director Constance Walter
Monday, March 16, 2015
Studying stars from underground
A
ll chemical elements, except hydrogen and helium, were created over
the course of billions of years by nuclear
reactions in the hot interiors of remote
and long-vanished stars. Although scientists understand the recipe of how stars
work, they don’t know the full range of
astronomical phenomena that occur. The
Compact Accelerator System Performing
Astrophysical Research (CASPAR) aims
to change that.
“This project could help complete
our picture about the mechanisms that
generate energies in stars and how the
elements in our universe are built,” said
Dr. Frank Strieder, Principal Investigator
for the project. The accelerator will help
researchers mimic nuclear fusion in stars.
“There is a famous saying,
‘We are all stardust.’ So we
need to have a better understanding of what happens in
stars.” That means going
deep underground,
Strieder said,
and Sanford
Lab is
With the ground supporting shotcrete in place, the CASPAR cavern on the 4850 Level is ready for
outfitting. Researchers hope to begin collecting data early next year.
the perfect place. “The infrastructure is in
place and we escape cosmic radiation.”
Over the past year, Syd DeVries has
been managing the design of CASPAR
utilities on the 4850 Level. With ground
support complete, construction crews
are ready to begin installing the utilities
needed to operate the experiment—electrical service, heating and air conditioning, and life safety systems.
“We want CASPAR researchers to
have the right space in which to operate
their experiment,” said DeVries, who is
the Underground Construction
Manager at Lawrence
Berkeley National
Laboratory (LBNL).
Experiments go
underground
to escape
cosmic
radia-
A three-dimensional drawing
of the completed CASPAR
experiment.
South Dakota Science and Technology Authority
tion. But everything around us contains
some level of radioactivity, including
rock and the materials used in construction. CASPAR is further protected from
radiation with a unique design: Walls at
the entrance and exit to the experiment
are two feet thick. Additionally, the doors
are lined with lead to mitigate any stray
neutrons from traveling outside of the
experiment.
DeVries expects the construction will
be completed in August. In the meantime,
members of the CASPAR team are
preparing the equipment and renovating
the accelerator at Notre Dame. When
construction is complete, CASPAR
researchers will begin moving into the
cavern. Strieder said the experiment will
be operational by January.
Strieder worked for several years with
the LUNA (Laboratory for Underground
Nuclear Astrophysics) project at Gran
Sasso Laboratory in Italy. LUNA was the
first underground accelerator to look for
nuclear fusion in stars. Now an Associate
Professor of Physics at the South Dakota
School of Mines & Technology, Strieder
said he is excited about coming to the
CASPAR experiment where he can
continue that research.
Lead, South Dakota