Page 15 - EUREKA! Fall 2017

“The discovery has changed

our understanding of the
innermost workings of matter

and can prove crucial to our
view of the universe.”

ries of energy production in the sun. This meant there was
something wrong with either the theories of the sun, or the
understanding of neutrinos.” SNO researchers discovered
that some of the electron-neutrinos change into other types
of neutrinos as they travel to the Earth.
“The determination that the electron neutrinos from the
sun transform into neutrinos of another type is very impor-
tant for a full understanding of the universe at the most
microscopic level,” SNO scientists said in a news release.
“This transformation of neutrino types is not allowed in the
Standard Model of elementary particles. Theoreticians will
be seeking the best way to incorporate this new informa-
tion about neutrinos into more comprehensive theories.
The direct evidence for solar neutrino transformation also
indicates that neutrinos have mass.”
That finding meshed with the results from the Super-Ka-
miokande detector in Japan, earning McDonald and Takaaki
Kajita the Nobel Prize. “The discovery has changed our Mil mossus. Ro elliquis qui volessitaes doluptaquas expernatum si Mil mossus. Ro elliquis qui volessitaes doluptaquas expernatum si destrum sit omnimuscia iusdae. Am nos aut ma voloribus et optatia
understanding of the innermost workings of matter and can destrum sit omnimus denderro berit facimag niminci liquae nonsequ atemperspit exerruntenis quid quam qui abor minctor eperfero eseniaesti
prove crucial to our view of the universe,” the Royal Swed-
ish Academy of Sciences said in a release. “Now the experi- a bustling 5,000-square-metre warren of scientists at work. ideas. For SNO, that was over a decade, and it took about plying operating funding, and the City of Greater Sudbury
ments continue and intense activity is underway worldwide SNOLAB has space for about 50 people per shift. The a decade to build the experiment, and a couple more years supporting public education. In January 2017, the CFI
in order to capture neutrinos and examine their properties. cavern that contained SNO — which stopped taking data before we had the answers we were looking for. But if you provided $28.6 million for three years of operations, and six
New discoveries about their deepest secrets are expected to in 2006 — is now home to the SNO+ experiment, which want a facility that attracts students and young scientists, months later the Ontario government added a $28.8 million
change our current understanding of the history, structure repurposed the original detector (replacing the heavy water having a sequence of experiments so there’s always some- five-year boost.
and future fate of the universe.” with liquid scintillator, an organic liquid similar to mineral oil thing that’s coming up with exciting results — and some- This collaborative spirit is reflected in the daily life of the
To visit SNOLAB, a half-hour drive west of downtown that gives off light when charged particles pass through it) thing that’s big enough so there are always different groups lab as researchers from institutions across the country and
Sudbury, you must arrive early in the morning at the facil- for a study of low-energy solar neutrinos and other physics coming together — that’s a wonderful fertile environment around the world work together on experiments and engage
ity’s surface building, a 3,000-square-metre, three-storey phenomena. There’s also a new Cube Hall cavern (18 metres for students and young scientists.” in lunchroom conversations, both technical and philosophi-
complex completed in 2005 to replace the original office long, 15 metres wide, 20 metres high) that’s ground zero for It cost $70 million to build SNOLAB, with excavation tak- cal, that flit from topic to topic in a kaleidoscope of scien-
trailer. In the gear room, you’re given heavy-duty neon yel- Carleton researcher Mark Boulay’s DEAP experiment (see ing place in 2007 and 2008, and cleanroom status achieved tific imagination.
low coveralls, boots, a hardhat, headlamp and safety glasses, “New window on the universe,” page TK). The Cryopit is in 2010. The Cryopit — the third largest space after the Although the focus at SNOLAB is physics — including the
and after changing you walk a couple hundred metres to the SNOLAB’s other large space, but the cleanroom facility also SNO cavern and Cube Hall — was designed specifically for Helium And Lead Observatory (HALO) project that’s using
No. 9 shaft — the main access portal to the Creighton Mine includes smaller “ladder labs” in the drifts that connect the cryogenic detectors; it’s isolated within the facility in case a neutrino detector to search for supernovas, and the PICO
and, at 2,175 metres, the deepest continuous mine shaft in caverns, a lunch room and meeting room. the detector warms and water needs to be vaporized and experiment that’s using a pair of bubble chambers to search
the western hemisphere. Scientists and journalists squeeze There was no guarantee that any of this would be built. expelled. Darryl Boyce, Carleton’s assistant vice-president for galactic dark matter — other disciplines are also part
into a double-decker elevator (known as a cage) with a few SNO was intended to be a single experiment, not a “facility,” of Facilities Management and Planning, played a critical role of the picture. Laurentian University’s Thomas Merritt, who
dozen miners beginning their shift, the gate is closed, and says Sinclair, because the latter implied a long-term com- in the construction of SNOLAB. “He provided outstanding uses fruit flies to study genetics and metabolism, has been
you descend at up to 50 kilometres/hour to 2,070 metres mitment that funders were not prepared to make. “But SNO management of the project,” says Sinclair, “just as if it were exploring physical responses to working at the 20 percent
below ground. You step out of the cage into a dark tunnel was such a success that we changed that idea,” he says. being carried out on the Carleton campus.” More than half higher levels of atmospheric pressure that exist two kilo-
(or drift) carved out of the rock, with walls covered in metal “Making a facility for a series of experiments was seen as the of the total funding was provided by the Canada Foundation metres underground. Seismic monitoring field experiments
screening, and walk about a kilometres and half, stepping right thing to do. Doing a single experiment has two prob- for Innovation (CFI). The remainder came from the Ontario have also been conducted in the lab.
aside to let mine vehicles pass, until reaching the entrance lems. First of all, these experiments take a lot of planning Innovation Trust, the Northern Ontario Heritage Fund and At its core, though, this is a physics facility — and SNO-
to the lab. Then you shower, put on clean clothing and enter and design, so there’s a long period where you’re testing FedNor, with the CFI, NSERC and member institutions sup- LAB is the core of Carleton’s physics enterprise, says Alain

14 science.carleton.ca science.carleton.ca 15