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Benjamin Franklin Medal awarded for Sudbury Neutrino Observatory measurements - Albert Einstein, Alexander Graham Bell among past recipients Canada NewsWire . Ottawa: Apr 23, 2007. pg. 1

Abstract (Summary) Dr. [Art McDonald] and his SNO team solved the 30-year-old puzzle of the "missing solar neutrinos" in their underground laboratory two kilometres below the surface of CVRD-INCO's Creighton Mine in Sudbury, Ontario. Their discovery that neutrinos (sub-atomic particles considered the basic building blocks of the universe) change from one type to another on their journey to Earth from the Sun modifies the long-held Standard Model of particle physics, and was designated as one of the most important scientific breakthroughs in the world in 2001 by the journal Science.

In 2006 the SNO team members were the first recipients of the John C. Polanyi Award for outstanding scientific achievement. Dr. McDonald is the Gordon and Patricia Gray Chair in Particle Astrophysics at Queen's, an Officer of the Order of Canada, and past recipient of the Gerhard Herzberg Gold Medal from NSERC Canada, the Tom W. Bonner Prize in Nuclear Physics from the American Physical Society, and the Bruno Pontecorvo Prize from Russia.

Full Text (588 words)

KINGSTON, ON, April 23 /CNW Telbec/ - Queen's University physicist Art McDonald and the team of scientific sleuths from the Sudbury Neutrino Observatory (SNO) have won another prestigious international award for their groundbreaking discoveries about the nature of matter and the structure of the universe.

This week at a gala ceremony in Philadelphia, Dr. McDonald will receive the 2007 Benjamin Franklin Medal in Physics, with co-winner Yoji Totsuka from the University of Tokyo, for "the discovery that neutrinos change flavour and have mass." The Franklin Institute Awards Program honours scientists, innovators and entrepreneurs who have made extraordinary scientific achievements, benefited humanity, advanced science, launched new fields of inquiry and increased the understanding of the universe.

Past winners of these medals - which date back to 1824 - include Albert Einstein, Alexander Graham Bell, Marie and Pierre Curie, and Orville Wright. More than 100 Franklin Institute Laureates have gone on to receive Nobel Prizes.

"This is an outstanding international recognition for SNO Director Art McDonald and the whole SNO Project team," says Vice- Principal (Research) Kerry Rowe. "The Franklin Institute Awards are among the world's oldest and most prestigious comprehensive science awards, with laureates representing some of the most distinguished scientific achievements of the past 180 years."

Dr. McDonald and his SNO team solved the 30-year-old puzzle of the "missing solar neutrinos" in their underground laboratory two kilometres below the surface of CVRD-INCO's Creighton Mine in Sudbury, Ontario. Their discovery that neutrinos (sub-atomic particles considered the basic building blocks of the universe) change from one type to another on their journey to Earth from the Sun modifies the long-held Standard Model of particle physics, and was designated as one of the most important scientific breakthroughs in the world in 2001 by the journal Science.

The SNO team includes more than 150 scientists from Queen's, Carleton, Laurentian and Oxford Universities; the Universities of Guelph, British Columbia, Pennsylvania, Washington and Texas; TRIIUMF, Berkeley, Los Alamos and Brookhaven National Laboratories and LIP, Lisbon.

"I am honored to accept the Franklin Medal for the scientific results obtained by our SNO team", said Professor McDonald.

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"This has been a tremendous collaborative effort over many years. Our success has arisen from the combined talents and hard work of many colleagues and from the tremendous support that we have received from our many international partners."

Events surrounding the Franklin Institute Awards this week include seminars, lectures by the nine recipients, interactive demonstrations and educational programs for Philadelphia area students. The Franklin medals will be presented on Thursday April 26.

Many of the Canadian SNO scientists are involved in the development of the new SNOLAB international underground science laboratory, expanding the existing SNO research laboratory 2 km underground in INCO's Creighton mine near Sudbury, Ontario. This new laboratory will provide opportunities for very sensitive future measurements of Dark Matter particles thought to make up about 25 per cent of the Universe, as well as other frontier measurements of neutrino properties made possible by eliminating almost all sources of radioactive background.

For further information on the Franklin Awards:

http://www.fi.edu/tfi/exhibits/bower/07/laureates.html

For further information on SNO:

http://www.sno.phy.queensu.ca/

Indexing (document details) Companies: Queens University ( NAICS: 611310 ) Dateline: Ontario Publication title: Canada NewsWire. Ottawa: Apr 23, 2007. pg. 1 Source type: Wire Feed ProQuest document ID: 1258765911 Text Word Count 588 Document URL: http://proquest.umi.com.myaccess.library.utoronto.ca/pqdweb?did=1258765911&sid=1&Fmt=3&cl ientId=12520&RQT=309&VName=PQD

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Giant lab in Sudbury observes tiny neutrinos ; Scientists gather, hoping to understand the nature of matter; [Ontario Edition] Peter Calamai . Toronto Star . Toronto, Ont.: Jun 15, 2000. pg. A.02

Abstract (Summary) Located 2,000 metres below ground in an abandoned mine, the Sudbury Neutrino Observatory is a 10-storey-high detection apparatus centred on a tank containing 1,000 tonnes of heavy water.

"Physicists talk about flavours of neutrinos. It's as if the taste buds of the other observatories were inoperative and they don't know if they're eating salt or sugar. Sudbury can uniquely tell whether what is causing the events in their tank is salt or sugar - whether the neutrinos are electron flavoured, muon flavoured or tao flavoured," [John Bahcall] said.

MICHAEL STUPARYK / TORONTO STAR FILE PHOTO / CANADA'S BIGGEST SCIENCE EXPERIMENT: [Art McDonald] rides up the Sudbury Neutrino Observatory during construction in 1996.

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Canada's biggest science experiment, the Sudbury Neutrino Observatory, has passed its inaugural trials with flying colours and is now working full-time to unravel scientific mysteries at both the cosmic and subatomic level.

News of the successful breaking-in of the $550-million SNO came as more than 400 physics and astronomy researchers gathered for an international conference in Sudbury to discuss the latest research on the elusive neutrino, one of the elementary particles of nature.

Neutrinos are produced naturally in the sun and by cosmic rays hitting the Earth's upper atmosphere. Trillions of them pass through our bodies every second with no effect, because they are little more than a tiny point without electrical charge and with almost no mass.

Yet knowing more about these ghostly particles is crucial for understanding the evolution of the universe and the subatomic nature of matter. Costly underground detectors in Japan and Canada are racing to capture and catalogue them and a third one is under construction in Minnesota for $200 million.

"SNO is very much on track. We are observing neutrinos from the sun that have all the characteristics you might expect," said Art McDonald, director of the Canadian-lead international project.

McDonald said that over the last six months, the SNO has demonstrated that it actually does possess the extreme sensitivity required for its delicate measurements.

"When we are ready to make statements about our findings, they will be definitive," McDonald said in an interview.

The key challenge for SNO and other neutrino experiments is to find evidence that neutrinos change form as they fly through space or pass through the earth.

Physicists believe there are three different "flavours" of neutrinos - electron, muon and tao.

Only a transformation from one flavour to another can explain why researchers using more primitive detectors have so far found fewer solar electron neutrinos than theory predicts.

Located 2,000 metres below ground in an abandoned mine, the Sudbury Neutrino Observatory is a 10-storey-high detection apparatus centred on a tank containing 1,000 tonnes of heavy water.

The rare collisons between neutrinos and the atoms of the heavy water - no more than 20 a day - are captured by 9,500 light

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sensors.

SNO's unique detection capability was praised by neutrino pioneer John Bahcall, a physicist from Princeton's Institute for Advanced Study who is attending the conference that officially begins tomorrow.

[Illustration] Caption: MICHAEL STUPARYK / TORONTO STAR FILE PHOTO / CANADA'S BIGGEST SCIENCE EXPERIMENT: Art McDonald rides up the Sudbury Neutrino Observatory during construction in 1996.

Credit: SCIENCE REPORTER

Indexing (document details) Author(s): Peter Calamai Dateline: Ottawa Section: NEWS Publication title: Toronto Star. Toronto, Ont.: Jun 15, 2000. pg. A.02 Source type: Newspaper ISSN: 03190781 ProQuest document ID: 426834141 Text Word Count 477 Document URL: http://proquest.umi.com.myaccess.library.utoronto.ca/pqdlink?did=426834141&sid=9&Fmt=3&cl ientId=12520&RQT=309&VName=PQD

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Physicist wins $1 million prize; Herzberg medal credits Canadian's work in Sudbury Mystery of solar neutrinos solved at underground site; [ONT Edition] Peter Calamai . Toronto Star . Toronto, Ont.: Nov 25, 2003. pg. A.02

Abstract (Summary) McDonald won the Gerhard Herzberg gold medal for his leadership of the observatory, a $600 million experiment into the nature of matter operating two kilometres deep inside a working Inco nickel mine. The prize guarantees $1 million in federal grants.

Named after the late Nobel laureate, the Herzberg medal also guarantees the winner $1 million in grants over five years from a federal funding agency, the Natural Sciences and Engineering Research Council.

Queen's University physics professor Art McDonald has won the Gerhard Herzberg gold medal for his leadership of the Sudbury Neutrino Observatory, the deepest research site in the world.

Full Text (419 words)

Exotic discoveries made at the country's most famous hole in the ground - Sudbury Neutrino Observatory - brought Canada's top research honour yesterday to the scientist in charge - and a promise of even more far-out findings to come.

Having solved the mystery of billions of solar neutrinos that got lost every minute, researchers at the observatory are now about to embark on a hunt for the missing one-quarter of the universe's total mass, a substance called dark matter because it doesn't show up in telescopes.

"We definitely will look for dark matter and there's significant international interest in taking part," said Art McDonald, a physicist from Queen's University in Kingston.

McDonald won the Gerhard Herzberg gold medal for his leadership of the observatory, a $600 million experiment into the nature of matter operating two kilometres deep inside a working Inco nickel mine. The prize guarantees $1 million in federal grants.

Other finalists were Richard Bond, a cosmologist at the University of Toronto, and John Smol, a lakes researcher at Queen's University.

Neutrinos are tiny particles that pervade the universe, zipping through dense lead as easily as ghosts slide through the walls at Hogworts. More than a hundred billion neutrinos passed through your thumb as you read this sentence.

The observatory's work in solving the mystery of missing solar neutrinos was ranked the No. 2 scientific breakthrough of 2002 by the editors of Science, one of the world's top journals.

As well, an American and a Japanese researcher shared half the 2002 Nobel physics prize for earlier neutrino measurements.

McDonald said yesterday that working with neutrino pioneers sparked an interest in the subject and led to the use of a mine cavern to screen out extraneous signals.

The physicist said he would devote some of the extra money to jump-start new types of experiments at the underground lab, which is also getting federal and provincial grants for a $45 millionexpansion.

Because the Sudbury observatory is the cleanest, deepest research site in the world, scientists from other countries are keen

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to run experiments there that need to be shielded from radiation and other external effects.

[Illustration] Queen's University physics professor Art McDonald has won the Gerhard Herzberg gold medal for his leadership of the Sudbury Neutrino Observatory, the deepest research site in the world.

Credit: Toronto Star

Indexing (document details) Author(s): Peter Calamai Section: News Publication title: Toronto Star. Toronto, Ont.: Nov 25, 2003. pg. A.02 Source type: Newspaper ISSN: 03190781 ProQuest document ID: 463873071 Text Word Count 419 Document URL: http://proquest.umi.com.myaccess.library.utoronto.ca/pqdlink?did=463873071&sid=9&Fmt=3&cl ientId=12520&RQT=309&VName=PQD

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BREAKTHROUGH OF THE YEAR

molecules are now known to exist in the thepolymerase opens and proteins in the earliest nematode and fruit fly. The coding for closes to bring DNA in life-forms. these molecules is containedin the DNA and pump newly made sequence. Some 100 of these tiny RNA RNA out, all throughthe So what's neu? With "genes"have been found in the gutbacterium sameopening. nearlyno mass, it's amaz- Escherichiacoli, and some 200 were un- Anotherset of small ing that anyone noticed coveredin DNA from mouse braintissue. nuclearRNAs turns out that they were missing. In the nematodeand fruitfly, they seem to to play a surprisingrole. But this year,the 30-year- be involvedin development;in E. coli, they These RNAs combine old case of the missingso- may facilitaterapid responses to environ- with proteinsto formthe larneutrinos was cracked. mental change and could serve similar spliceosome, which re- One of the great tri- functionsin mammals. moves noncoding se- umphs of science in the The processby whichthe more familiar quence from nascent * past centuryhas been un- messengerRNA (mRNA)is generatedalso mRNA.Researchers dis- derstanding how stars gained new respect in 2001. Duringtran- covered this year that burn nuclear fuel, yet scription,mRNAs are built to matchthe se- spliceosome RNAs, not Caseclosed. Sudb ,ur ry observatory fi- physicistsquickly discov- quenceof the activegene, andthey then in- the proteins,control the nallynabbed missi ing [ neutrinos. ered that something was structthe cell'sprotein factory, the ribosome, removalof unwantedse- wrong.Expected products how to builda protein.The discoveryof key quence.This has spawneda new field,"ribo- of the stellarfireball-neutrinos of a partic- proteinsinvolved in splicingtogether mRNA's zymology,"aimed at clarifyingand harness- ulartype called"electron" neutrinos-were codingregions added details to this scenario. ing RNA'senzymatic potential. In one exper- not nearlyas abundantas requiredby the Also, in June,high-resolution pictures cap- iment,researchers forced RNA enzymes,or straightforwardtheory. turedthe yeast RNA polymerase1H-which "ribozymes"to evolveby selectingfor those In 1998, physicistspresented evidence builds the mRNA based on the gene's thatare ableto replicateRNA. These results thatseemed to explainthe discrepancy:They sequence-in action.During transcription, help show that RNA could have preceded showedthat neutrinos "oscillate" from one

Peering Into 2002 astronomicaldatabases. Often called the World-WideTelescope, it shouldopen the heavensto richdiscoveries in comingyears. Science'seditors once againread the tea leavesfor hot researchareas in the com- Next in genetics. Chronicdiseases generally result from the inter- ingyear. play of multiple genes. Geneticists have made much progress i1~ pinningdown the genetic basis of single-gene disorders,but Stem cells abroad.The BushAdministration the roots of more complex diseases have been elusive. has limited federalsupport for human em- _l ^ With the human genome sequence in hand, re- bryonicstem (ES)cell researchto work on searchers expect to make clear progress in de- cell lines derivedbefore 9 August2001. That lBI--HBt^l terminingthe relativecontributions of vari- still leaves the door open for unfetteredre- ous genes to problems such as heart search in privatelyfunded labs and in coun- disease, cancer,and diabetes. tries with less restrictive rules. Look for progressin translatingresults from mouse to -. _; Optical clocks and con- human ES cells as governmentsaround the _*. .^^B^ stants. Because they're world clarifytheir rules and more scientists * . based on higher frequency gain access to the humancell lines.But also %^>:visible light waves rather watch for legal and commercial entangle- "7 than microwave radiation, ments as companies race to stake their ii optical clocks are an order claimsin the wide-openfield. A of magnitude more accurate than previous instru- Proteomics.Genes tell cells what - J ments. They should lead to proteinsto make,so figuringout how i more precise global posi- proteinsinteract is vitalfor leveraging genetic knowledge in medicine tioning systems and a new generation of experiments to test and andbiotech. It's a toughassignment: Although there might be as few challenge the fundamental constants of nature. In 2002, expect an as 35,000genes, there might be millionsof proteins.But the will is increasingpace of researchas optical clocks become the gold stan- I there:Biotech companies and funding agencies are pouring hundreds dardsby which to judge other important measurements. us of millionsof dollarsinto untanglingthe proteome.Next could year z see the firstprotein-based drug targets from biotech proteomics. Visualization of complex systems. New imaging technology and ever-faster computers will come together to allow a closer Eyeson the sky. Earlyin 2002,the secondof the Geminiproject's look at biological molecules and their interactions. Recent lab suc- .0 8-metertelescopes will be dedicatedin Chile,following its sibling, cesses with electron cryomicroscopyand electron microscope to- whichsaw first light in Hawaii2 yearsago. The Very Large Telescopes mography are merging with computer simulation to create new . . (alsoin Chile),now fitted with new"adaptive optics," reportedly see views of how proteins work with each other. And labeling tech- u as wellas the HubbleSpace Telescope. Next year, big sky efforts such niques for tagging proteins, lipids, and other biomolecules are as the SloanDigital Sky Survey should continue to producesolid re- evolving rapidly toward the goal of watching cell signaling as it sults.Also on the horizonis theVirtual Observatory, a vast network of occurs in space and time.

2444 21 DECEMBER2001 VOL294 SCIENCEwww.sciencemag.org Scorecard2000 flavor as the electron to an- (such neutrino) Inwhich the editorsface the musicand their balls. other(such as the muonor tau neutrino).If polish crystal the electronneutrinos turned into another va- "--. Infectiousdiseases. There were few breakthroughsin drugdevelopment for x the world's and malaria-and new vaccine riety as they streamedaway from the sun, " majorkillers-HIV, tuberculosis, thatwould explainthe shortfallof electron ! ~ } candidateshave only recentlyentered the testingphase. On the otherhand, neutrinos.But therewas still no directevi- ^._>/1 interestin tacklinginfectious diseases kept surging-especially after the 11 dencethat neutrino oscillations are to blame *X? Septemberattacks and the spateof anthraxletters. forthe solarneutrino paradox. ThisJune, all thatchanged, thanks to the - New views of the ocean. A satellite called SeaWiFSprovided the first SudburyNeutrino Observatory(SNO), a multiyear,global picture of photosynthesison bothland and sea anddetect- 1000-tonsphere of heavywater 2 kilometers ed a burstin ocean plantgrowth during an El Nino-LaNifia shift. SeaWiFS belowEarth's surface in Sudbury,Ontario. Af- ~.~f,;/talso revealedhow large"planetary" waves pump nutrients to the oceansur- tersome delay, SNO scientists announced that i,^_HIk face. However,data from NASA'sTerra satellite, which will add ocean fluo- theyhad found the missingsolar neutrinos- rescenceto the picture,are still awaiting validation. andthey were, indeed, changing flavor. SNO was able to count the numberof '"x~\RNA surveillance. It has been a banneryear for RNAinterference (RNAi) electronneutrinos coming from the sun and ~(C \ (see Runners-Up,p. 2443). 2001 has seen the identificationof the enzyme, compareit to the totalnumber. The number J appropriatelycalled Dicer, that kicksoff the wholeRNAi process by chopping of electronneutrinos was still too small to ,/ up double-strandedRNA precursor molecules into small RNAs.Dicer also z matchnuclear physicists' theories, in agree- <_4HR has been implicatedin the controlof gene expressionby smallRNAs during ment with past experiments.However, the development.Just last month,the RNAifield took anotherleap forward with the finding totalnumber of neutrinosmatched that the cell can boost RNAiby amplifyingthe numberof smallRNAs through the ac- .Z incoming | expectations:The predictionswere correct, tion of a cellular-directedRNA polymerase. but the neutrinoswere swappingidentities I on the wayto the detector. C/ --", hFollowthe money.With the exceptionof the NationalInstitutes of Health,presi- z ( ? \ dentialcandidate George W. Bush's support for research during the campaignwas Genomes take off. Barely3 yearsago, re- AWOLthis spring in his first proposed budget. But legislators repaired much of the ? searcherswere edging hesitantly to the start- \~> damage,giving several science agencies more than they hadrequested. At the 31ing gate in the race to sequencethe human sametime, research budgets in mostof Europeand Asia were protected from the . genome.But eggedon by competition,a pri- worsteffects of a globaldownturn, because governments continue to see science vate effortand an internationalpublic con- andtechnology as a goodway to bolstertheir long-term economic prospects. u sortiumgalloped into the home stretchearly , this year,achieving the first publicationsof Quarksoup. In2001, scientists at the RelativisticHeavy Ion Collider (RHIC) at BrookhavenNational in New saw evidenceof | draftcoverage of the 3.3 billion bases that " \ Laboratory Upton, York, "jet define our species. The drafts cover the / I quenching":a sign that nuclearparticles might have melted into their compo- . ^' E gene-containingportions of our DNA but I /)nent parts,creating a quark-gluonplasma. Although the resultsare still open havegaps of varyingsizes. The big surprise \\', to interpretation,and theorists are talking about new concepts such as "col- ored it hasbeen a in research.If all mowhen the draftswere revealed:Our genetic

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Deep underground discoveries bring top award for Ontario physicists Margaret Munro . CanWest News . Don Mills, Ont.: Nov 15, 2006. pg. 1

Abstract (Summary) EDS: "Today" in copy is Wednesday

Full Text (671 words)

EDS: "Today" in copy is Wednesday

Physicists who went two kilometres underground in a Northern Ontario mine to solve one of the mysteries of the universe have picked up Canada's newest science prize.

The team at Sudbury Neutrino Observatory (SNO) has won the inaugural John C. Polanyi Prize and $250,000 for experiments conducted in a super-clean lab in the Inco. Ltd Creighton mine.

Polanyi, of the University of Toronto, who won the Nobel Prize for chemistry in 1986, will award the prize to the team today for discoveries about tiny sub-atomic particles called neutrinos that zip through the Earth and everything on it, but are so elusive they are nearly impossible to catch.

The group led by Art McDonald of Queen's University in Kingston, Ont. discovered the elusive particles change into different forms as they zip from the sun to Earth, solving the mystery of what happened to neutrinos that scientists believed had gone missing on the journey. This led to the revision of the Standard Model, the theory describing the elementary particles that form the building blocks of all matter.

The SNO team ran its experiments deep underground to observe neutrinos away from the cosmic rays and radiation at the Earth's surface, which interfered with their detection.

The work has been earning the scientists accolades and headlines for years. It has also attracted close to $50 million in new money that is enabling them to double the size of the underground lab, devise further experiments and build a workshop for themselves on the surface.

OPTIONALCUT

"After years of doing 'an' experiment and living in trailers, now we have a permanent above-ground facility," says McDonald, who will lead Polanyi and other dignitaries around the expanding facility today. They will also head underground, where excavation crews are digging out a new clean lab the size of a four-storey house to supplement the original ten-storey facility, which houses the sphere used to study the neutrinos.

The 12-metre diameter sphere is filled with $330-million worth of heavy water, and surrounded by almost 10,000 computerized detectors. When a neutrino hits the nucleus of one of the heavy water atoms bang on, which occurs about 10 times a day, it produces a tiny burst of light and allows the scientists to characterize the different forms.

McDonald says the team will pull the plug on the sphere in November and return the heavy water to Atomic Energy of Canada Ltd. The plan is to replace it with a fluid normally used to produce soap for the next round of experiments; the fluid won't degrade the giant acrylic vessel and will be ideal for the next round of experiments.

The Sudbury observatory is the deepest, cleanest research site in the world, and McDonald says teams from Britain and the U.S. are keen to collaborate with Canadians to use the facility to step up the search for dark matter and rare forms of radioactivity. Several proposed international projects worth $10 million to $20 million each are under review by various funding agencies.

The Canadian Foundation for Innovation is financing the bulk of the $50-million expansion to turn SNO into "SNO-Plus."

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McDonald says the site is ideal for studying the so-called dark matter left over from the Big Bang that is believed to make up 25 per cent of the universe.

One of the proposed SNO-Plus projects is to look for dark matter particles called WIMPs, short for weakly interacting massive particles.

"It's the sort of thing that is in the spaces when you look out on a starry night," McDonald says of the poorly understood dark matter.

McDonald says it should be possible to detect them using super-sensitive devices planned for SNO-Plus, much like the earlier experiments that detected and characterized neutrinos.

While it may sound obscure, McDonald says the work on dark matter is important.

"It really is the cutting edge," he says. "I mean, gee whiz, if you don't know what 25 per cent of your universe is, that's a pretty big question."

Credit: CanWest News Service

Indexing (document details) Author(s): Margaret Munro Document types: News Publication title: CanWest News. Don Mills, Ont.: Nov 15, 2006. pg. 1 Source type: Wire Feed ProQuest document ID: 1163725741 Text Word Count 671 Document URL: http://proquest.umi.com.myaccess.library.utoronto.ca/pqdweb?did=1163725741&sid=2&Fmt=3&cl ientId=12520&RQT=309&VName=PQD

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Particle research earns physicist major award Tom Spears . CanWest News . Don Mills, Ont.: Jan 20, 2005. pg. 1

Abstract (Summary) The Bruno Pontecorvo Prize, named for an Italian-Russian scientist who once worked at Chalk River, Ont., is the world's heavyweight award in particle physics. And today Art McDonald of Queen's in Kingston, Ont., will pick it up for his work as head of the Sudbury Neutrino Observatory, a two-decade project that has been paying off since its first results flowed out in 2001.

The Sudbury lab, two kilometres deep in a Canadian Shield nickel mine, uses heavy water to block the neutrinos as they rush through the Earth itself, and sensitive light detectors to count the flashes as the particles hit.

The Sudbury experiments, which continue today, have boosted Canadians in the physics world. A service that monitors science journals found that for months in 2003, the first three reports from Sudbury were the world's three most quoted research papers in any field of physics.

Full Text (437 words)

(Copyright CanWest News Service 2005)

OTTAWA - A Queen's University physicist who runs an underground lab that studies weird particles from the sun has just won the top Russian award for particle physics. It's worth just $1,000, but carries international glory.

The Bruno Pontecorvo Prize, named for an Italian-Russian scientist who once worked at Chalk River, Ont., is the world's heavyweight award in particle physics. And today Art McDonald of Queen's in Kingston, Ont., will pick it up for his work as head of the Sudbury Neutrino Observatory, a two-decade project that has been paying off since its first results flowed out in 2001.

The annual prize comes from the Joint Institutes of Nuclear Research in Dubna, outside Moscow.

Pontecorvo was an enigmatic scientist. Italian-born, he immigrated to Montreal in 1943 and ended up at Chalk River, near Ottawa, where Canada was getting its feet wet in nuclear research.

He stayed until 1949 before moving to England. In 1953, he moved to Moscow, where the opportunities for research in his field were greatest. It didn't endear him to western governments, since nuclear scientists in Russia were assumed to be bomb-builders.

In fact, McDonald, who met the much-travelled Italian decades later, says this was abstract research unrelated to weapons.

Pontecorvo was the first to develop a theory that neutrinos from the sun change their nature as they speed through space.

Neutrinos, smaller than atoms, are particles produced in stars like our sun in numbers too large to count. Millions of neutrinos are rushing harmlessly through your body as you read this.

But they are also very hard to observe, and their nature remains mysterious.

Something about them, physicists gradually realized, didn't add up. Either their understanding of how the sun produces neutrinos was wrong, or the neutrinos were somehow changing their basic form as they flew through space. That would make our basic understanding of matter itself wrong.

It was Pontecorvo who proposed that the tiny particles could change.

"He's the one who proposed what turned out to be correct," McDonald says. "And we are the ones who have most proven Pontecorvo's theories."

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Ottawa Citizen

Credit: CanWest News Service; Ottawa Citizen

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Neutrino trappers may stun world; [SU2 Edition] Michael Smith Toronto Star . Toronto Star . Toronto, Ont.: Aug 2, 1992. pg. B.6

Abstract (Summary) Unfortunately, no scientific team has yet been able to detect the "right number" of neutrinos. This could mean that their detectors weren't good enough. Or that something unexpected is happening in the sun's core. Or that neutrinos don't behave the way physicists think they should.

"We are poised to try to resolve the puzzle," says Art McDonald, the Queen's University physicist who is director of the $60 million Sudbury Neutrino Observatory (SNO).

The experiments were mainly studying low-energy neutrinos. One, by a Soviet-U.S. team in the Caucasus Mountains, found almost no neutrinos; the other, conducted by a U.S.-European group in the Alps, found about two-thirds the expected number.

Full Text (846 words)

Deep in the heart of Sudbury's Creighton mine, Canadian scientists are quietly preparing to scoop the world on one of the most slippery questions in modern physics: What's really going on inside the sun?

The problem, in a nutshell, is that the sun produces heat and light through a process known as fusion. And calculations show that fusion should produce a certain number of neutrinos - tiny, elusive particles that are among the fundamental building blocks of the universe.

Unfortunately, no scientific team has yet been able to detect the "right number" of neutrinos. This could mean that their detectors weren't good enough. Or that something unexpected is happening in the sun's core. Or that neutrinos don't behave the way physicists think they should.

If the last possibility proves true, it would spark a scientific gold rush. Everything from the innards of atoms to the age of the universe would be subject to re-examination.

"We are poised to try to resolve the puzzle," says Art McDonald, the Queen's University physicist who is director of the $60 million Sudbury Neutrino Observatory (SNO).

At the moment, scientists are pooling their expertise in what McDonald calls "a bunch of basement labs" in Canada, the United States and Britain to design and build the observatory.

In Sudbury, the project's focus is on a hole in the ground where construction crews are in the early stages of building the neutrino detector - 2,000 metres (6,800 feet) straight down. The detectors are deep underground to avoid interference from cosmic rays.

The detector will be housed in a barrel-shaped cavity the height of 10-storey building, surrounded by laboratories carved out of the solid rock. The lab rooms have been dug; the detector cavity is about one-third finished.

McDonald is hoping to turn up some important answers about neutrinos soon after the neutrino observatory starts up early in 1995.

The project has taken on extra significance because two recent international experiments aimed at solving the neutrino problem came up with conflicting answers.

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And there were conflicting answers from two earlier experiments looking for high-energy neutrinos. A Japanese study found half the expected number while the earliest neutrino search, started in 1967 in a gold mine in South Dakota, found about one-third the expected number.

"It looks as if we will have the chance to clarify the position," says a project physicist, John Simpson of the University of Guelph.

The Sudbury experiment is also aimed at high-energy neutrinos, but Simpson says it will have more accurate numbers than the Japanese or South Dakota projects.

Those experiments saw between 20 and 30 neutrinos a year and "SNO will get thousands per year," Simpson says.

Simpson expects SNO to confirm the earlier results - that a certain number of neutrinos are missing. Then the compelling question would be why.

"Either there is something in the sun that we don't understand, or there are properties of neutrinos that haven't been observed so far," McDonald says.

In the first case, physicists will have to rethink their picture of the sun's inner workings - an exciting job, but probably not one that would lead to fundamental discoveries.

But if it turns out that neutrinos do strange things - changing from one variety to another is the favored guess - physicists will have to rebuild much of their science, from the smallest sub-atomic scale to the universe itself.

That's because to change varieties, neutrinos would need to have mass, something that's ruled out in the standard picture of how all matter is put together.

SNO, by design, is the first experiment that will be able to distinguish between the two possibilities to explain the "neutrino gap."

At the heart of the Sudbury detector will be a plastic sphere, 12 metres (40 feet) across, filled with 1,000 tonnes of heavy water. (Heavy water, whose hydrogen atoms have an extra particle in their nucleus, is used as a coolant in Candu-type nuclear reactors.)

The rest of the detector cavity will be filled with 7,000 tonnes of ordinary water. Suspended in it, about 2 1/2 metres (8 feet) outside the plastic sphere, will be 10,000 photo-multipliers - electronic devices, much like door-opening electric eyes, that can amplify any light that strikes them.

The 7,000 tonnes of ordinary water is used to block the normal background radiation of the surrounding rock, while the heavy water does the actual detecting.

When a neutrino smacks into an atom of heavy water, it creates a burst of light. Careful analysis can tell where the neutrino came from and what type it is.

SNO's cost is a bargain. Use of the Inco Ltd. mine is free and the heavy water is borrowed from Atomic Energy of Canada Ltd. "Because we're in Canada, we can do this $500 million experiment for $60 million," McDonald said.

[Illustration] Caption: Star drawing (Elicierto): diagram of Sudbury Neutrino Observatory

Indexing (document details) People: Simpson, John Author(s): Michael Smith Toronto Star Section: SCIENCE Publication title: Toronto Star. Toronto, Ont.: Aug 2, 1992. pg. B.6 Source type: Newspaper ISSN: 03190781 ProQuest document ID: 456455411 Text Word Count 846

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Volume 194, number 2 PHYSICS LETTERS B 6 August 1987

A HEAVY WATER DETECTOR TO RESOLVE THE SOLAR NEUTRINO PROBLEM

The Sudbury Neutrino Observatory Collaboration

G. AARDSMA a, R.C. ALLEN b J.D. ANGLIN c, M. BERCOVITCH c, A.L. CARTER d, H.H. CHEN b, W.F. DAVIDSON c, P.J. DOE b, E.D. EARLE e, H.C. EVANS r, G.T. EWAN f, E.D. HALLMAN g, C.K. HARGROVE c, p. JAGAM a, D. KESSLER d, H.W. LEE r, J.R. LESLIE f, J.D. MACARTHUR f, H.-B. MAK f, A.B. McDONALD h, W. McLATCHIE f, B.C. ROBERTSON f, J.J. SIMPSON a, D. SINCLAIR ~, P. SKENSVED f and R.S. STOREY ~ University of Guelph, Guelph, Ontario, Canada NIG 2Wl h University of California, Irvine, CA 92717, USA National Research Council of Canada, Ottawa, Ontario, Canada K1A OR6 d Carleton University, Ottawa, Ontario, Canada K1S 5B6 " Chalk River Nuclear Laboratories, AECL, Chalk River, Ontario, Canada KOJ 1JO r Queen's Universio~, Kingston, Ontario, Canada K7L 3N6 g Laurentian University. Sudbury, Ontario, Canada P3E 2C6 h Princeton University, Princeton, NJ 08544, USA ' O.~ford University, Oxford OX1 3NP, UK

Received 27 April 1987

The observation of the following three reactions: ved-~ppe; vxe~vxe; and vxd~vxpn (where v~ is any left-handed neutrino) in a heavy water Cerenkov detector which is being designed, allows the solar 8B ve flux, spectrum and direction to be measured. In addition, the total solar 8B neutrino flux, direction and integral spectrum, independent of neutrino flavor, may be determined to provide several independent methods to resolve the solar neutrino problem.

The only direct information on the reactions which theoretical framework of Wolfenstein [6], have power the sun is carried by neutrinos escaping from shown that a mechanism exists whereby, if this mix- its dense interior. The pioneering experiment of ing of eigenstates is postulated, a large fraction of ve Davis et al. [ 1 ] did not observe the expected [2] flux created in the solar interior could be converted into of neutrinos and the discrepancy, known as the solar u,(v~), even for very small vacuum mixing angles. neutrino problem (SNP) is widely considered a Weinberg [7] suggested that the sun is a unique major problem in modern physics. Two categories of source offering a rare opportunity to search for neu- solutions of the problem have been extensively dis- trino oscillations to test unification theories beyond cussed. The first assigns some deficiency to the stan- the electroweak sector. He argued that such theories dard solar model (SSM) and many mechanisms have lead naturally to the heaviest neutrino mass of about been suggested to lower the central temperature of 10-3 eV, a range for which solar experiments, with the sun thus reducing 8B production [ 3 ]. The second matter enhancement, are particularly sensitive. Other assigns some deficiency to our knowledge about neu- suggested solutions to the SNP include the possibil- trino propagation. Pontecorvo originally suggested ity of neutrino decay [8] or neutrino magnetic that the reduction in v~ flux at earth may be caused moment [ 9]. by large mixing angle oscillations of neutrinos In this letter we discuss how the sensitivity of a between weak interaction eigenstates [4]. More large heavy-water Cerenkov detector to the solar 8B recently, Mikheyev and Smirnov [5], following the ve flux, spectrum and direction, to the total solar 8B

0370-2693/87/$ 03.50 © Elsevier Science Publishers B.V. 321 (North-Holland Physics Publishing Division) Volume 194, number 2 PHYSICS LETTERS B 6 August 1987

5-14 MeV. Monte Carlo simulations of the detector indicate that the energy of 10 MeV electrons can be measured to 15% accuracy (a), their direction determined to 25 °, and their location to 1 m. An essential consideration in the design of a solar neutrino experiment is that the backgrounds be made very low. We intend to locate the detector in the Creighton mine near Sudbury, Canada, under a fiat overburden, at a depth of 2070 m to reduce cosmic-ray muon flux to about 100/d. The sensitive volume of the detector is shielded from radioactivity in the rock by 1 m of low activity concrete and 3 m of purified light water. All components of the detector would be made of low activity materials. A detailed assessment of the detector performance and background has been reported elsewhere [ 10]. The detector would identify neutrinos through three complementary reactions: inverse-beta decay of the deuteron, neutrino-electron scattering, and neutrino-disintegration of the deuteron. The rates for these reactions under several scenarios are summa- rized in table 1. 20.Om The ve flux, spectrum, and direction would be Fig. 1. A conceptual design of a detector for 8B solar neutrinos. measured via the charged-current reaction Neutrinos interacting in the heavy water can produce relativistic electrons which emit Cerenkov light. This light is detected in an ve +d~p+p+e. (I) array of phototubes covering 40% of the surface. The detector would be located at a depth of 2070 m in the Creighton mine near Monoenergetic neutrinos produce electrons which are Sudbury, Canada. almost monoenergetic with kinetic energies approx- imately Ev- 1.44 MeV [ 11 ], and hence this reaction neutrino flux independent of the neutrino flavor, and is well suited to spectroscopic studies. The electrons to the v~.~ spectrum and direction, could be exploited would have an angular distribution with respect to to distinguish among the suggested solutions of the the neutrino direction given by W(0e)=l-~ SNP, hence resolving this problem. In particular, such ×cos(0~). an experiment allows the sun to be used as a distant The second reaction to be used in neutrino-elec- neutrino source for physics experiments free of tron scattering: assumptions of the standard solar model, and also Vx+e~vx+e. (II) allows a definitive test of the standard solar model free of complications from proposed new neutrino In standard electroweak theory, while all neutri- properties. This experiment would have a sensitivity nos can scatter by the neutral current process, only some 50 times greater than that of the Davis exper- the v¢ can interact through the charged current with iment [ 1 ]. the result that the cross section for ve [ 12 ] is 6 times A conceptual design of our proposed detector is larger than that for v, [ 13 ] or v,. Thus, this reaction shown in fig. 1. It would consist of 1000 t of 99.8% is mainly sensitive to the Ve flux; but with an inde- pure heavy water (D20) contained in a transparent pendent measurement of the Ve flux and spectrum as tank viewed by phototubes covering 40% of the sur- described above, it can give a measure of the total face area. Relativistic particles are detected by the neutrino flux. For a 8B v~ spectrum, the yield for this Cerenkov light they produce in the water. To address reaction is an order of magnitude smaller than that the SNP it is necessary to study electrons of energy of reactio,: (I) as can be seen in table 1. Electrons

322 Volume 194, number 2 PHYSICS LETTERS B 6 August 1987

Table 1 Response of the detector to solar neutrinos. The rates above the indicated threshold are given in events per kilotonne year (kT yr) assuming a 8B neutrino flux [ 19] of 4× 106 cm 2 s ~except in the last row, as indicated. The total scattering rate is given together with the v,,¢ component, in parentheses, to indicate the increase in rate for reaction II over the value expected from a measurement of reaction I.

Case v,.d~ ppe v~e~ vxe vxd ~ pvxna

> 5 MeV >9 MeV > 5 MeV >9 MeV standard solar model 6500 1530 730 (0) 120 (0) 710 A. vacuum oscillations 2170 510 320 (78) 52 (12) 710 B. matter oscillations E,,=9 MeV 2500 50 430 (53) 30 (14) 710 E,.=2 MeV 65 15 115(110) 18(17) 710 C. non adiabaticlimit in 8B energy range 2500 650 325 (72) 58 (10) 710 standard solar model wrong, flux l.3×106cm 2s ~ 2170 510 240(0) 40(0) 240 Assumes 20% neutron capture efficiency. from this reaction are kinematically constrained to fying and monitoring water and acrylic for radioiso- the forward cone, thus providing excellent direc- topes is continuing [ 10]. tional information on the flux, In heavy water, these Mikheyev and Smirnov [ 5 ] observed that, in mat- events can be separated from those of reaction (I) ter, vacuum neutrino oscillations can be amplified by their strong forward peaking though a better and a number of authors [ 5,15-18 ] have elaborated measurement would come from a light water fill with on this to show three new solutions to the SNP in the no events from reaction (I). Because the electron oscillation parameter space, with typical cases B, C, spectrum gives an integral of the neutrino flux, and D to be discussed below. The essential feature and because of the lower yield, this reaction is less of all oscillation hypotheses for solving the SNP is useful for spectroscopic studies than reaction (I) (see that there be a substantial v~(v~) flux with a corre- fig. 2). sponding reduction in the Ve flux from the SSM pre- Finally, the total (left-handed) neutrino flux, diction. Thus, the charged-current rate is decreased independent of neutrino flavor, can be measured by as required to explain the SNP, vxe scattering has a the neutral-current reaction rate roughly 30% higher than expected on the basis of reaction (I) as shown in table 1, and the neutral- vx+d-~vx+p+n. (III) current rate remains consistent with the SSM, This reaction rate would be determined by counting unchanged by any oscillation solution as already the free neutrons produced. Chen [14] has pointed emphasized [14]. In addition, for some cases, gross out that this reaction is particularly important for distortions of the 8B ve spectrum would be observed resolving the SNP because it gives a direct measure as shown in fig. 2. of the solar 8B neutrino production independent of Case A. Vacuum oscillations of three neutrino fla- oscillations. The rate for this reaction is large, but vors with large mixing angles and with mass-squared the detection efficiency for free neutrons depends differences (Sm 2) greater than 10 -~° eV 2, This is sensitively on the choice of capture reaction. The basically the Pontecorvo oscillation solution. Key simple choice, i.e. capture on the deuteron, has a low features are the rates for reactions (II) and (IID rel- efficiency due to competing capture reactions and ative to reaction (I) as shown in table 1, and diffusion out of the DzO. Nevertheless, we have used unchanged ve spectral shape. it for the detection rates shown in table 1. There is Case B. For values of (8rn 2) in the range a serious background problem for this reaction from (0.33-1.5) × 10-4eV 2, the high-energy part of the 8B photo-disintegration of the deuteron. Work on puri- spectrum above an energy Ec is converted to v,(v~).

323 Volume 194, number 2 PHYSICS LETTERS B 6 August 1987

Etecfron energy (MeV) [ 18]. In this case, the detector would observe an 5 I0 enhanced Ve flux at night while observing the total 200 i .... i .... neutrino flux to be constant. ...-. Case E. Neutrino decay [8]. In this case, the ve ".jB spectrum, as observed by reaction (I), would be dis-

150 toned in a way similar to that in case C, because more of the low-energy ve would have disappeared. If ve is c the lightest neutrino, then v,(v~) cannot be pro-

c~_t .' duced in Ve decay, so reactions (II) and (III) rates ,C :~ 100 j, would be determined from measurements of reaction (I). Otherwise, reactions (II) and (III) rates

t~ A might be greater than expected from reaction (I), depending on decay mode.

50 ' '" •.... '\ Case F. Neutrino magnetic moment [9]. In this case, one would observe a correlation of the neutrino ," O '\ flux with the solar cycle, as well as a semi-annual correlation with the intercept of the solar equatorial plane and the ecliptic plane. 0 19~ 2~0 3~0 40 50 60 70 80 Case G. Standard solar model wrong. In'this case, Number of detecfed phofoetecfrons the observed spectrum in reaction (I) would be that Fig. 2. Calculated spectra for reactions I (capitals) and II (low- expected for SB decay. Reactions (II) and (III) would ercase) for some possible solutions of the SNP. Curves A and a have rates consistent with the Ve flUX observed with are for vacuum oscillations (case A in text); B and b are for con- reaction (I), as shown in table 1, rather than the pre- version of high energy ve (case B); C and c are for non-adiabatic conversion (case C). It is clear that reaction I is significantly bet- dicted rates of SSM. Furthermore, all three reaction ter than reaction lI for measuring the neutrino spectrum rates would be independent of time. To study neutrino physics independent of the SSM, The SNP could be explained by 2

324 Volume 194, number 2 PHYSICS LETTERS B 6 August 1987

[8] J.N. Bahcall, S.T. Petcov, S~ Toshev and J.W.F. Valle, Phys. Lett. B 181 (1986) 369. This experiment could not be contemplated with- [9] M.B. Voloshin and M.I. Vysotsky, ITEP Report No. 1 1986; out access to a large amount of heavy water and a L.B. Okun, M.B. Voloshin and M.I. Vysotsky, ITEP Report suitable deep site. A stock heavy water exists in Can- No. 20 (1986), to be published. ada for use in future CANDU reactors and we are [ 10] G.T. Ewan et al., Sudbury neutrino observatory, Report grateful to AECL for agreeing to lend 1000 tonnes SNO-85-3 Queen's University, Canada (1985), unpub- for this project. The encouragement and cooperation lished; H.H. Chen, in: Proc. Conf. on Solar neutrinos and neutrino of the International Nickel Company (INCO) has astronomy (Homestake, 1984), AIP Conf. Proc 126 (ALP, been vital to this project. The support by NSERC and New York, 1985) p. 249; NRC (Canada), and NSF and DOE (US), is grate- D. Sinclair et al., Nuovo Cimento C 9 (1986) 308; fully acknowledged. E.D. Earle et al., Proc. Second Conf. on the Intersections between particle and nuclear physics (Lake Louise, 1986), AIP Conf. Proc. 150 (AIP, New York, 1986) p. 1094. References [ 11 ] F.J. Kelly and H. Uberall, Phys. Rev. Lett. 16 (1966) 145. [ 12] R.C. Alien et al., Phys. Rev. Lett. 55 (1985) 2401. [13] L.A. Ahrens et al., Phys. Rev. Lett. 51 (1983) 1514; 54 [ 1 ] R. Davis Jr., D.S. Harmer and K.C. Hoffman, Phys. Rev. (1985) 18. Lett. 20 (1968) 1205; [14] H.H. Chen, Phys. Rev. Lett. 55 (1985) 1534. J.K. Rowley, B.T. Cleveland and R. Davis Jr., in: Proc. Conf. [ 15] H.A. Bethe, Phys. Rev. Lett. 56 (1986) 1305. on Solar neutrinos and neutrino astronomy (Homestake, [ 16] S.P. Rosen and J.M. Gelb, Phys. Rev. D 34 (1986) 969. 1984), AIP Conf. Proc. 125 (AIP, New York, 1985) pl. [17] W.C. Haxton, Phys. Rev. Lett. 57 (1986) 1271; [2] J.N. Bahcall, Rev. Mod. Phys. 50 (1978) 881; S.J. Parke, Phys. Rev. Lett. 57 (1986) 1275; J.N. Bahcall et al., Rev. Mod. Phys. 54 (1982) 767. E.W. Kolb et al., Phys. Len. B 175 (1986) 478; [3] B. Kuchowicz, Rep. Prog. Phys. 39 (1976) 291. V. Barger et al., Phys. Rev. D 34 (1986) 980. [4] B. Pontecorvo, Zh. Eksp. Teor. Fiz. 53 (1967) 1717 [Sov. [18] A.J. Baltz and J. Weneser, Phys. Rev. D 35 (1987) 528; Phys. JETP 26 (1968) 984]; M. Cribier, W. Hampel, J. Rich and D. Vigaud, Phys. Lett. V. Gribov and B. Pontecorvo, Phys. Lett. B 28 (1969) 495. B 182 (1986) 89. [5] S.P. Mikheyev and A. Yu. Smirnov, Nuovo Cimento C 9 [ 19] J.N. Bahcall, in: Proc. Conf. on Solar neutrinos and neu- (1986) 17. trino astronomy (Homestake, 1984), AlP Conf. Proc. 126 [6] L. Wolfenstein, Phys. Rev. D 17 (1978) 2369; D 20 (1979) (ALP, New York, 1985) p. 60. 2634. [7] S. Weinberg, Proc. XXIII Intern. Conf. on High energy physics, Berkeley, CA, July 1986 (World Scientific, Singa- pore, 1986).

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