A Joint Fermilab/SLAC Publication Dimensions of Particle Physics Issue

dimensions volume 03 of particle physics symmetryA joint Fermilab/SLAC publication

issue 08/09

oct/nov 06 symmetry | volume 03 | issue 08/09 | oct/nov 06

dimensions of particle physics symmetryA joint Fermilab/SLAC publication

On the Cover Every particle physics laboratory makes room for visiting scientists from around the world, and almost all particle physicists need a home away from home on a regular basis. Accommodations, such as these at Fermilab, tend toward the austere, but then so do the lifestyles of physicist travelers.

Photos: Sandbox Studio

Office of Science U.S. Department of Energy 3 Commentary: InterAction Collaboration 26 Deconstruction: ILC Cryogenics “In the months and years ahead, the majority of The proposed International Linear Collider will journalists who tell the story of 21st-century parti- use 16,000 superconducting cavities made cle physics will do an excellent job. From time of niobium, and scientists around the world are to time, inevitably, they will get it wrong—at least working on the cryogenic system needed to as we see it. A true test of our character is how keep the cavities cool. we react to this level of media coverage.” 28 Gallery: Quark Park 4 Signal to Background A new sculpture garden created in a vacant Lightning strikes; rainy-day roof rehab; right on downtown lot in Princeton, New Jersey, Quark time; taking care of business, lyrically; ‘critters’ Park wants its visitors “to have a moment of as safety monitors; big jump needed to be top- enjoyment, a glimpse of beauty, and a sense of cited; letters. the dimensions of contemporary science.” 10 Close Quarters 32 Essay: Joe Willie During their visits at other labs, physicists learn “How does a high school in upstate New York that it’s a small world after all, especially when become a hot spot for monitoring the correla- they stay in no-frills dorms. The lab life helps tion between cosmic rays and solar flares? The build professional networks and long-lasting story goes back to a flier…about an outreach friendships across the planet. program called QuarkNet in the spring of 2000.” 16 Catching neutrinos in China ibc Logbook: Cosmic Microwave Background The first particle physics experiment with lead- John Mather and George Smoot shared the 2006 ership almost equally split between China Nobel Prize for experiments on board of the and the United States would be located deep COBE satellite. It took Mather’s experiment only beneath the mountains of Southern China, nine minutes to record enough data to confirm looking for neutrino interactions. the big-bang theory. 22 The European Strategy for Particle Physics bc 60 Seconds: Acceleration of Particles The CERN Council Strategy Group has presented Imagine a surfer riding a wave. If the surfer pad- its recommendations in particle physics, focusing dles at the right speed and gets on a wave at on a policy for Europe to “maintain and strengthen the right time, the surfer will be accelerated to its central position” in the field. the speed of the wave. from the editor

Emerging particle physics in China Traditionally, the big five particle physics laboratories have been Fermilab and SLAC in the United States, CERN in Switzerland, DESY in Germany, and KEK in Japan. However, a changing world economy is bringing new players into the game. China, in particular, is currently investing rapidly in basic science research, including particle physics. During my recent trip to Beijing, I was impressed by the Institute of High Energy Physics’ dedication to building a rich, long-term particle physics research program. The Chinese realize that they must grow their program over time through domestic investments and international collaboration. One such collaboration is described in this issue of symmetry. If funded, the Daya Bay neutrino experiment would be a world-class experiment led by Chinese and US physicists, and the largest scientific collaboration ever between these two countries. Domestically, new facilities at IHEP will make a significant contribution to particle physics, commensurate with a relatively young program. Meanwhile, expatriate scientists are beginning to return to China to work in an expanding research effort. More foreign scientists are visiting China, and the Americans and Europeans with whom I spoke were all enthusiastic about working on the new Chinese experiments. Support for basic science in China is currently very strong. During conversations, I was astounded to hear that ex-scientists and engineers make up about two thirds of the Chinese government. I am sure this is helping drive investment in basic research, but that interest in science is also reflected in many other ways. The English-language Chinese newspaper available in the guest house at IHEP featured a research science story on the front page every day I was there, something unheard of in US newspapers. Chinese particle physics research is going through a rapid transition, leading to a more elaborate and serious program. Leading Chinese scientists acknowledge that it will take perhaps 15 years or more to reach the upper tier of global particle physics programs, but they will make valuable contributions in selected areas before then. The international community should support and include China: Its programs will enhance the global particle physics effort and bring rewards beyond the scientific results. David Harris, Editor-in-chief

Symmetry Editor-in-Chief Publishers Print Design and Production PO Box 500 David Harris Neil Calder, SLAC Sandbox Studio MS 206 650 926 8580 Judy Jackson, FNAL Chicago, Illinois Batavia Illinois 60510 USA Executive Editor Contributing Editors Art Director Mike Perricone Roberta Antolini, LNGS Michael Branigan 630 840 3351 telephone Peter Barratt, PPARC 630 840 8780 fax Managing Editor Stefano Bianco, LNF Designers www.symmetrymagazine.org Kurt Riesselmann Reid Edwards, LBNL Aaron Grant Anilou Price [email protected] Catherine Foster, ANL Staff Writers Tara Kennedy Elizabeth Clements James Gillies, CERN (c) 2006 symmetry All rights Silvia Giromini, LNF reserved Brad Plummer Web Design and Production Heather Rock Woods Jacky Hutchinson, RAL Xeno Media symmetry (ISSN 1931-8367) Siri Steiner Youhei Morita, KEK Hinsdale, Illinois is published 10 times per year Kelen Tuttle Marcello Pavan, TRIUMF by Fermi National Accelerator Mona Rowe, BNL Web Architect Laboratory and Stanford Interns Perrine Royole-Degieux, IN2P3 Kevin Munday Ben Berger Yuri Ryabov, IHEP Protvino

Linear Accelerator Center, 06 | oct/nov symmetry | volume 03 issue 08/09 Rachel Courtland Yves Sacquin, CEA-Saclay Web Design funded by the US Department Karen Acklin of Energy Ofﬁce of Science. Dave Mosher Boris Starchenko, JINR D.A. Venton Maury Tigner, LEPP Alex Tarasiewicz Jacques Visser, NIKHEF Web Programmer Linda Ware, JLab Mike Acklin Ute Wilhelmsen, DESY Tongzhou Xu, IHEP Beijing Photographic Services Fermilab Visual Media symmetry Services

2 commentary: interaction collaboration

The media have a central role in telling the story of research in particle physics. We need to put aside our differences and keep our eyes on the big picture if we are to make the most of this vast resource, say members of the InterAction collaboration.

Particle physics and the press These are exciting times for particle physics, and the world’s press are taking notice. As the Large Hadron Collider prepares to begin operations, as the International Linear Collider becomes an ever more clearly defined project, as programs for neutrino physics and astrophysics flourish, and most of all as long-awaited discoveries reveal the secrets of the universe, our friends in InterAction collaboration members met in Hamburg recently with other particle physics communicators. the media will share the adventure. Their stories Photo courtesy of the InterAction collaboration. and articles, TV programs, blogs, and podcasts will inform and inspire others with the spirit of excitement that particle physicists are feeling admiration for all projects and experiments that at the start of the 21st century. lead to discovery—or one that begrudges The journalists who tell our story will have every word of praise for others’ work. Without wildly varying backgrounds, skills, and points of fail, the media will pick up on our tone. So view. Their pieces will cover the spectrum of will our colleagues, our students, scientists in science journalism. They will define and describe; other disciplines, and we ourselves. It will be compare and contrast; make judgments and part of what defines the kind of field that we are. express opinions; and praise and criticize. Writing Competition will always exist, and this is a in language that is accessible to their readers, good thing. People care passionately about their they will at times seem wanting in their grasp of work. Of course they want to see it recognized, scientific subtleties. Sometimes they will appear and defend it if it is unfairly criticized. But we to lack appreciation for something that we care have everything to gain by maintaining perspec- deeply about; occasionally they may even give tive. There will be hundreds of stories during more credit than we deserve. the years ahead. Today’s lukewarm review will be It is accepted wisdom that the press almost tomorrow’s encomium—and vice versa. We always get it wrong. Actually, in our experience, should take them all in our stride, because we ultimately they get it just about right. In the months are in this together for the long haul. We all and years ahead, the majority of journalists who want to discover how the universe works. It’s a tell the story of 21st-century particle physics will big universe with room, and credit, enough for do an excellent job. From time to time, inevitably, everyone. they will get it wrong—at least as we see it. A true test of our character as a field is how we react to This article is being published simultaneously in the October issues of symmetry and CERN Courier (www.cerncourier.com). this level of media coverage. At a time of extraordinary scientific opportu- Members of InterAction, a collaboration of particle-physics com- nity in particle physics, we must keep our eyes municators from laboratories around the world (www.interac- on the science and enjoy the privilege of taking tions.org): Roberta Antolini, INFN Gran Sasso; Peter Barratt, PPARC; Natalie Bealing, CCLRC/RAL; Stefano Bianco, INFN part in discovering how the universe works. We Frascati; Karsten Buesser, DESY; Neil Calder, SLAC; Elizabeth should equally enjoy the opportunity afforded by Clements, ILC; Reid Edwards, Lawrence Berkeley National the media’s interest. Laboratory; Suraiya Farukhi, Argonne National Laboratory; James Gillies, CERN; Judith Jackson, Fermilab; Marge Lynch, In the past, there have been occasions when Brookhaven National Laboratory; Youhei Morita, KEK, ILC; our field has devolved into warring camps, Christian Mrotzek, DESY; Perrine Royole-Degieux, IN2P3, ILC; reading each new press article with suspicion, Yves Sacquin, DAPNIA CEA; Ahren Sadoff, Cornell University 06 | oct/nov symmetry | volume 03 issue 08/09 LEPP; Maury Tigner, Cornell University LEPP; and Barbara quick to take offense at every real or imag- Warmbein, ILC. ined slight or bias. It’s time to change this model. Do we want to be seen as a fractious, conten- tious community beset by invidiousness, or as a unified community of committed scientists confronting a golden age of discovery? We have the choice. We can set a tone of respect and

3 signal to background

Lightning strikes, Tevatron blinks; rainy-day roof rehab; congratulations arrive right on time; taking care of business, lyrically; menagerie of ‘critters’ as safety monitors; big jump needed to be top-cited; letters. Photo: Tim Koeth, Rutgers University Photo: Tim Koeth,

Lightning strikes, currents flow through the Rainy-day rehab Tevatron blinks ground,” Johnson says. From the day it was completed The highest-energy particle Power sources and commu- in the early days of Fermilab, accelerator in the world, nications networks can be the design of the Meson Lab Fermilab’s Tevatron, boasts disrupted, especially those fea- roof has been an aesthetic four miles of particle-acceler- turing long, unshielded cables. success and a structural night- ating circumference. But Those disruptions can terminate mare. It leaks. Always has. during thunderstorms it can the beam and delay experi- The water-welcoming weak- become a bull’s-eye for stray ments. Resuming operations ness lies in the signature of lightning bolts that demon- can take several hours, de- the design, the corrugated steel strate the intimidating power pending on how long it takes arches: the ridges run perpen- of nature. “The Tevatron is to track down problems and dicular to the flow of water from a magnificent and wonderful make repairs. a rainfall. “They do not encour- thing,” says Tevatron opera- Thunderstorms also affect age water to move from the tions specialist Todd Johnson, the Tevatron in other annoying roof,” says Fermilab’s Elaine “but it’s also very fragile.” ways. When lightning strikes, McCluskey, project engineer for The energy contained in a fire alarms in any of the dozens the upcoming roof repairs. The large thunderstorm often sur- of Tevatron buildings can trip. roof has many steel-to-steel passes that of an atomic bomb. “I once spent an entire night shift connection points, which provide When clouds build up extra doing nothing but driving to inlet opportunities for water. electrons, they need to get rid buildings where alarms were set Without a water-tight coating, of the charge somehow. A off,” Johnson says. Overall, he the roof has been leaking since thunderous blast of lightning sees the complex Tevatron as it was built. often results, and the energy in a surprisingly robust system— Repairs began in early a single lightning bolt is often but still susceptible to the power October to make the roof water- 100,000 electron volts with a cur- of nature. “When we see a tight. The renovation will include rent of about 1000 amperes. thunderstorm approaching,” power-washing, filling in cavities Disruption of accelerator opera- Johnson adds, “we cross our with a mastic-type material and tions doesn’t require a direct fingers.” applying two coats of a spray-on hit. “When lightning strikes, large Dave Mosher rubber coating. The coating

4 Photo: Fermilab 06 | oct/nov symmetry | volume 03 issue 08/09

material, used in many indus- It absolutely had to presentation the next day,” says trial roofing applications, will arrive on time Fermilab shipping manager dry as a sheet. “The material’s The inaugural beam for the Claudie King. “We put it on the manufacturer said the Meson CERN Neutrinos to Gran Sasso next flight.” The greeting arrived Lab roof was one of its most (CNGS) project took just 2.5 on time and was presented to unique uses,” McCluskey says. milliseconds to fly 732 km Eugenio Coccia, director of the The trademark Fermilab through the earth from Geneva, Laboratori Nazionali del Gran colors, bright blue and orange, Switzerland, to its destination Sasso (photo). will also be restored, honoring at the Gran Sasso underground Like Fermilab’s beamline, the original vision of founding laboratory near Rome on CNGS will help physicists director Robert Wilson and Monday, September 11, 2006. understand the role that the designer Angela Gonzales. The But in preparation for the dedi- puzzling neutrinos played in the duo attended to virtually every cation ceremonies at Istituto early universe. “Of all the known detail of the site’s appearance. Nazionale di Fisica Nucleare particles, neutrinos are the most At the Meson Lab, they called that day, a congratulatory gift mysterious,” says Oddone. “In for the use of corrugated steel had to make its own quick tran- the years ahead, neutrino exper- culverts, laid side by side, to sit by air across ten times that iments at Gran Sasso and create giant scallops, with an distance (more than 7100 km), around the world will discover orange inner surface and from Fermilab to Gran Sasso. the fascinating secrets of neutri- a blue outer surface to give The gift was a framed poster, nos and how they shaped the added texture. McCluskey featuring a picture of Fermilab’s universe we live in.” says, “The architectural legacy Wilson Hall at sunset, mounted Siri Steiner of Dr. Wilson is something we next to an image of the mine- try to preserve as we remodel head for the Soudan buildings and look to future Underground Laboratory in facilities.” northern Minnesota—represent- The renovated Meson Lab ing the beam origin and detec- will house R&D projects for the tor hall for Fermilab’s NuMI/ Photo: Laboratori Nazionali del Gran Sasso proposed International Linear MINOS beamline and experi- Collider. The west side of the ment, covering a similar distance building will belong to the through the earth as the CNGS development of detector com- beam. Fermilab director Pier ponents; the east side, to the Oddone had written his con- testing of superconducting gratulations and best wishes radiofrequency cavities for par- (in Italian) across the center, ticle acceleration. Repairs to before the framed greeting the roof are expected to be flew overnight from Chicago completed in two months–if the to Rome. “We had it all weather cooperates. packed up and found out they D.A. Venton needed it for some kind of

5 signal to background

Takin’ care of (SLAC) business When 20-year-old Ryan Auer set out to ﬁnd his very ﬁrst job, he didn’t expect to wind up at the Stanford Linear Accelerator Center, let alone on stage in front of over 1000 people at the lab’s annual Family Day. A college sophomore, Auer worked this summer with the campus Heating, Ventilating, and Air-Conditioning engineers. The job inspired him to change his major from civil to mechanical engineering. As a parting tribute before heading back to school, he wrote and performed these SLAC-happy lyrics to the Bachman-Turner Overdrive tune Takin’ Care of Business. Rachel Courtland

Watch a performance of the song in the online edition of symmetry at www.symmetrymagazine.org. Photos: Diana Rogers, SLAC

6 Takin’ Care of Business by Ryan Auer

We made our debut, Back in 1962; It’s all controlled at MCC. Faster than the speed of light, SLAC hosted the first website, And you can take a tour here for free. The Archimedes text, What will they uncover next? Come and view the linac from afar. The wires intertwine, Up and down the beamline, We’ve got an experiment called BaBar. And we’ll be... Takin’ care of business, here at SLAC, Takin’ care of business, no turnin’ back, Takin’ care of business, everyday, Takin’ care of business, and everything’s okay. Three Nobel Prizes, And buildings of great sizes, We get our funding from the DOE. Particle acceleration, And our own fire station, We’ve got the great Dr. Panofsky. Several injectors, And we’ve got 30 sectors. We’re just right off the interstate. PEP & SPEAR, You can find it all right here, Just come on in through Alpine Gate. And we’ll be... Takin’ care of business, here at SLAC, Takin’ care of business, no turnin’ back,

Takin’ care of business, everyday, 06 | oct/nov symmetry | volume 03 issue 08/09 Takin’ care of business, and everything’s okay. Visit SSRL, Or come stay at our hotel, Come to watch the gamma rays burst. If the tunnels are too small, Just come to Collider Hall, But please make sure that safety comes ﬁrst. Now before you embark, Don’t forget about the quark, Discovered in End Station A. I hope you liked my song, Now I must be movin’ on, Enjoy the rest of Family Day. And we’ll be... Takin’ care of business, here at SLAC, Takin’ care of business, no turnin’ back, Takin’ care of business, everyday, Takin’ care of business, and everything’s okay.

7 signal to background

tored, and radiation at Fermilab names is often part of lab lore. consistently falls below radia- In one legend, an employee tion standards set by the US working in frustration on a Department of Energy. radiation instrument in the late Throughout the site, radiation 1960s dubbed his instrument levels are maintained at the the “albatross,” alluding to the normal, background levels poem The Rime of the Ancient found in the natural environ- Mariner and the sailor who ment; higher levels are found wears an albatross around his only inside accelerator enclo- neck as a burden. The “scare- sures and at a few posted, crow,” an instrument mounted fenced-off locations. Workers on a tripod (left), would—if it who enter experimental areas detected unacceptable levels that might be exposed to mea- of radiation in an area—warn surable levels of radiation wear people to stay out of the area, detection badges. The majority like crows warned to stay out of radiation exposure occurs of a cornﬁeld. A piece of hard- when accelerator components ware called the “aardvark” Safety critters need repair; the maintenance collects little, termite-like bits monitor lab site inside accelerator enclosures, of radiation data and has a The instrumentation team of of course, is always done after long, protruding trunk-line. The Fermilab’s Environment, Safety the beam is turned off. For an “chipmunk” makes a chirping & Health Section is the care- extra level of safety, Fermilab sound, and “hippos” are rotund taker of a unique menagerie: policy mandates that workers and gray. albatrosses, chipmunks, hip- in radiological areas may only The stories behind some of Photo: Butch Hartman, Fermilab pos, pterodactyls, scarecrows, be exposed to levels that are the names have been lost. The and an aardvark to name a less than one-third of the “pterodactyls”? “I really don’t few. These critters are radia- annual limit allowed by the know how they were named,” tion detection instruments, DOE for radiological workers. says John Larson, team co- designed and built in-house. As part of Fermilab’s care- leader. “But it’s a conversation “Everyone here knows what ful monitoring program, the starter; it’s not boring. You they are, but no one else in radiation detection “critters” get tired of hearing acronyms the world would,” says Butch keep a watch on radiation levels all the time.” Hartman, team co-leader. throughout the lab’s acceler- D. A. Venton The level of radiation at ator complex and beyond. The Fermilab is stringently moni- origin of the instrument

Letters

More travel stories Reading the September issue of symmetry, I was reminded of when Larry Rosenson of MIT told me the story some years ago of being stuck on a long ﬂight next to talkative woman. She insisted on telling him how great her son was. “He did this, he did that….” Larry tried everything he could think of to stop her chatter. Finally, he took out a book titled something like “Elementary Particle Physics.” The woman saw the title and said, “Oh, I see you are studying elementary particle physics. My son studied advanced particle physics.” Harvey L. Lynch, Stanford Linear Accelerator Center Make your own data card Thanks for the pictures of the pocket particle card [September issue]. I can’t wait to laminate the two halves together. Yes, you will be able to tell its a reproduction, but it still looks too cool! John Sandow, Harper College, Illinois

Letters can be submitted via [email protected]

8 Big jump needed to a ratio of one in 14. The ascent 252 (1998), 4064 citations), be top-cited from 50 to 2000 was a relatively which received all of its citations In the realm of the top-cited easy climb, with the ratio rang- in less than 8 years. papers in particle physics, life is ing from 1 in 1.8 (50+ to 100+) to Peak publication periods for indeed lonely at the top. Since 1 in 4.7 (250+ to 500+). papers in the 2000+ range are 1951, only 45 particle physics The three most highly-cited 1998–99, with 12; and 1973–74, research papers have climbed papers are Steven Weinberg’s with seven. In 1998–99, the 12 to the level of 2000 or more 1967 “Model of Leptons” (Phys. papers span a wide range of citations; and of those 45, only Rev. Lett. 19 1264 (1967), 4602 interests, from theoretical three—for a ratio of one in 15— citations); Makoto Kobayashi papers on strings and extra have reached the pinnacle of and Toshihide Maskawa’s 1973 dimensions (small and large), to 4000 or more citations. “CP-Violation in the Renormal- experimental papers on cos- symmetry | volume 03 | issue 08/09 | oct/nov 06 | oct/nov symmetry | volume 03 issue 08/09 In fact, that last part of the izable Theory of Weak mology and neutrino oscillations. climb is the hardest of all. The Interaction” (Prog. Theor. The 1973–74 period featured all second-hardest step is getting Phys., Vol. 49 No. 2 (1973), seven top-cited papers on the- the ﬁrst 50 citations. The spires 2792 citations); and Juan ory papers of the electroweak database lists some 235,000 Maldacena’s “Large N Limit of and strong interactions, which papers that have received fewer Superconformal Field laid the groundwork for the than 50 citations; only 16,643 Theories and Supergravity” Standard Model. crossed the threshold of 50, (Adv. Theor. Math. Phys. 2 231- Heath O’Connell, Fermilab

Top-cited papers in HEP Number of papers Ratio

4000 + 3 1 out of 15

Number of 2000 + 45 1 out of 3.4 Citations

1000 + 151 1 out of 4

500 + 612 1 out of 3.3

250 + 2,035 1 out of 4.7

100 + 9,494 1 out of 1.8

50 + 16,643 1 out of 14

up to 50 235,000

Papers with 2000+ citations

8 8

Number of 7 7 Papers

6 6

5 5

4 4

3 3

2 2

1 1 81 71 91 74 87 78 79 72 73 94 80 90 97 70 75 76 04 84 96 98 83 85 82 92 93 95 89 977 999 986 988 19 19 19 2001 19 1 19 19 1 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 1 1 2000 2002 2003 20 Journal Year

9 Photos: Sandbox Studio 10 CLOSE QUARTERS By Dave Mosher

During their stays at other labs, physicists learn that it’s a small world after all.

symmetry | volume 03 | issue 08/09 | oct/nov 06 11

Photos: Fermilab (3), MINOS Collaboration (1), KEK (1), IN2P3 (1) “ You really can’t work in a focused way if you’re distracted by amenities.”

A little after midnight, foreign voices and scents a short walk to work for a fraction of a motel room price of dinner drift from the kitchen and down the halls of tag. “Everything you need is less than a mile from your Dorm 1. Slavic dialogue stirs me from sleep and the aroma room,” Ross says about the on-site guest houses at various of cooked kielbasa sausage grabs my full attention. As laboratories around the world that he has stayed at. my eyes adjust to the darkness, the monotone surround- A bed close to the workplace is even more sacred to ings of a Fermilab dorm room begin to materialize: a small guests who defy normal circadian rhythms by working on desk, a slender dresser, a quaint painting of a Native round-the-clock experiments. For these physicists, sleeping American pot. The room is dull. It’s cramped. And the bed through most of the day and arriving at work around 11 is really, really small. p.m. is nothing out of the ordinary. “It’s not what a typical As a summer intern in Fermilab’s Office of Public business traveler is used to,” Peterson says. Affairs, I slept, ate, worked, and played in the same spaces Roommates’ schedules can be so contrasting that it’s as scientists. Although my stay may have been short, it common for a guest not to see fellow residents for presented convenient and unique opportunities to learn almost a week or, in extreme cases, never meet them at and write about high-energy particle physics. all. “When I stayed at DESY in Germany, there was one But for scientists staying for a few weeks, months, or other resident on the living room couch during the eve- sometimes years at a time, living on-site is much more nings. When I came in, I always saw him sleeping,” than a convenience—it is a boon to their inquiry-driven life- Peterson says laughing, “but I never actually met him.” styles. Every particle physics laboratory makes room for Even if guests are more like ghosts to one another, visiting scientists from around the world, and almost all most find a way to introduce themselves. As a Japanese particle physicists need a home away from home on a reg- postdoc at Fermilab, Hidekazu Tanaka says working from ular basis. Accommodations tend toward the austere, 8 a.m. to 11 p.m. prevented him from meeting residents but then so do the lifestyles of physicist travelers. in his dorm—until a severe thunderstorm rolled through the site. “There’s an alarm box in my room and it started No-frills necessities screaming at five in the morning,” he says. “I saw all the Working under tight budgets, scientists appreciate people in the dorm coming out of their rooms and asking affordable dorms, apartments, and guest houses—tem- each other, ‘What is going on?’” porary but comfortable homes that bring the world’s Confusing surprises also lie in wait at other labs. At best and brightest together under one roof. “No frills” is DESY in Germany, refrigerators are compartmentalized a response as common as an electron if you ask resi- and locked up to keep things tidy. Remembering the key dents about their abodes. to unlock food from chilly cubbyholes can be frustrating, “Many of the rooms don’t even have an alarm clock,” says Barbara Warmbein, an International Linear Collider says Tom Peterson of Fermilab. “I have to remember communicator at DESY. But food isn’t the only thing to take one with me. More than once I’ve asked my col- incarcerated at the lab. “The TV and VCR are behind glass leagues to wake me up by pounding on the door so people won’t take them. When you want to change because I forgot it.” channels, you have to get up and stick your fingers into During his ongoing 30-year career, the engineer with little holes in the glass,” she says. “It’s a little annoying.” peppery-gray hair has stayed at labs across the globe. Peterson finds the quarters close and the rooms drab, but Feeding international collaboration he insists scientists aren’t looking for a Hilton, much less Besides work, scientists have to eat, making the on-site a motel. “Physicists just need a convenient place to crash,” kitchen a prime place to bump into other members of he says. the high-energy physics community. Among the clanking Fermilab’s Marc Ross finds having a bed nearby helps of dishes and pans, it’s not unusual to hear three differ- 06 | oct/nov symmetry | volume 03 issue 08/09 keep him on task. “You really can’t work in a focused ent conversations in three different languages going at way if you’re distracted by amenities,” he says. While often once. “In KEK dorms around 6 p.m., everyone is in the more spacious, off-site vacancies frequently lack the kitchen stir-frying dinner in a wok,” says Alan Schwartz, convenience of on-site accommodations, which provide a University of Cincinnati physicist working in Japan. “If residents with fully-equipped kitchens, TV lounge areas, anyone hangs out in the dorms, it’s usually in the kitchen.” laundry facilities, furnished rooms and—most importantly— Schwartz, who is working on the Belle experiment at

13 Photos: SLAC (1), DESY (1), MINOS Collaboration (2), “ If anyone hangs KEK (1), Fermilab (1) out in the dorms, it’s usually in the kitchen.”

KEK, says there is an important aspect when it comes to Kicking back or kicking a ball scientists simply hanging out together. “When they get Labs may provide appealing spaces for discussing new together, they talk about science and share their ideas,” ideas in physics or simply the latest gossip, but they also he says, “so having common areas where people can welcome on-site sports and clubs to help scientists kick chat is important.” back. From soccer, baseball, golf, and ultimate Frisbee Because dorms mostly lack appealing spaces and res- leagues to rock and jazz bands, folk dancing, and model idents can get bored hiding away in bedrooms, cafeterias airplane clubs, something to do after work is just around at labs across the globe are hot spots for networking and the corner. sharing ideas. “But what you talk about in a cafeteria When it’s warm outside, soccer fever brings a lot of depends enormously on who you’re sitting with,” says Nan scientific visitors to the turf. “I love to play soccer at Phinney, an accelerator physicist at Stanford Linear Fermilab, but the mosquitoes are really annoying,” says Accelerator Center. “If you’re there for a two-day meeting, Ulrich Nierste, a theorist from Germany’s University of it’s probably going to be conversation about Science with Karlsruhe. But in a way, Nierste doesn’t mind the itchy a big S,” she says, “and you sort of continue working but in critters. “They keep you running very fast,” he says. a more relaxed fashion.” For Nierste, however, soccer isn’t just for kicks. “Having During lunch in lab cafeterias, Warmbein often sees sports is very important for a lab because you get to do conversing physicists hash out concepts on the closest something with colleagues that isn’t work,” he says. Just writing material they can find. “Napkins are a sought- like working together on an experiment, time on the field after thing for scribbling on and exchanging ideas,” she helps build long-lasting friendships and close networks says. “It seems like physicists are always talking about among labs across the planet. “Physicists move a lot science over lunch.” [from one work place to the next] and we’re pretty mixed Still, physics isn’t always on the minds of scientists up,” Nierste says. “But in a way, it’s like being part of one during a meal. “During the winter at CERN, you can’t sit big family.” down without someone talking about skiing,” Phinney When Giulia Zanderighi stayed at Fermilab, she wasn’t says. If she bumps into long-lost friends while visiting looking to break a sweat on the volleyball court. “But a lab, Phinney says the conversation is more natural and someone suggested I could play and I really got into it,” light-hearted. “Whenever I go to a lab for a big confer- she says. The CERN theorist’s favorite matches took ence, I’ll see people I haven’t seen in a long time and it’s place on Wednesday afternoons, when theorists faced off a big pleasure,” she says. “Sitting with your friends is with experimentalists. “I made quite a few friendships quite a lot of fun.” through it,” she says. “I sometimes see players at CERN; For Peterson, meeting up with his buddies for a bite to it makes the world smaller.” eat is a major highlight during trips. “Conversing over All of the amenities that make on-site life tick—includ- meals with colleagues is often the most enjoyable part of ing the cramped housing, common eating areas, and my visit,” he says. “I think it helps foster better communi- after-work clubs—strongly remind Peterson of a university cation.” Peterson can’t say for sure why, but he’s found environment. “I think all of the labs have tried to create a that people respond more quickly to emails and phone collegiate atmosphere,” he says. “There’s something about calls when they know the person on the other end of it that helps foster collaborative efforts.” the line. “Dining together really makes the business of Collaboration and collegiality can go too far, however. communicating easier,” he says. The college dorm tradition of “borrowing” food is honored But meals aren’t required to create important commu- around the world, as I learned one night when my seques- nication opportunities—simply grabbing a drink is a great tered kielbasa sausage went missing. I told myself it was excuse to chat. At Fermilab, workers meet over a drink for the good of science. 06 | oct/nov symmetry | volume 03 issue 08/09 and share laughs at the Users’ Center while coffee breaks in the cafeteria are a favorite among physicists at CERN. “A standing joke about CERN is that if someone goes to the office looking for a colleague and they’re not there, they’re in the cafeteria having coffee,” says Christoph Paus of CERN. “People love the cafeteria.”

14 FNAL The ﬁrst particle physics experiment with leadership almost equally split between China and the United States would be located deep beneath the mountains of Southern China, looking for mysterious neutrino interactions.

By Kendra Snyder, Brookhaven National Laboratory with additional reporting from Beijing by David Harris

Illustrations: Sandbox Studio 16 Buried deep in the mountains of southern China, a new neutrino experiment would rely on a series of Chinese nuclear reactors and the brains of scientists from several countries. The proposed Daya Bay neutrino experiment is one of many particle physics projects with an international backing, an increasing necessity as experiments grow in size, price, and complexity. Yet unlike its predeces- sors, Daya Bay is the first particle physics experiment with leadership almost equally split between the United States and China, a move some hope will strengthen the scientific relationship between the two economic powerhouses. “We expect this to be the largest international collaboration in basic science in China and the biggest US-China collaboration,” says Yifang Wang, deputy director of the Institute of High Energy Physics (IHEP), Beijing. Lawrence Berkeley National Laboratory physicist Kam-Biu Luk, one of two scientific spokesmen for the Daya Bay project, says, “Science is getting a lot of attention in China. They are investing more and more in basic research as well as in technology. This is a good time to work with China, and it may create a lot of opportunities for the United States in the future.” With almost two miles of underground tunnels and eight identical 100-ton detectors, the Daya Bay project awaits results from an important US review conducted in the middle of October. In the mean time, US and Chinese scientists, technicians, and engineers, along with their counterparts from Hong Kong, Taiwan, Russia, and the Czech Republic, are working to make the project a reality, and ultimately answer some of the most puzzling questions about one of nature’s most elusive particles—the neutrino.

Small particle, big questions 06 | oct/nov symmetry | volume 03 issue 08/09 Neutrinos are uncharged elementary particles produced naturally from the sun and cosmic rays. The particles morph, or oscillate, among three ﬂavors— electron, muon, and tau—as they travel through space, people, buildings, and even Earth itself, interacting rarely with other matter. Scientists have char- acterized two of these oscillations in detail, and are seeking to measure details of the third, the switching of tau-type neutrinos to electron-type neutrinos. A crucial quantity related to this oscillation—known as the mixing

17 HUNAN JIANGXI FUJIAN

GUANGXI GUANGDONG

• Canton

Daya Bay

• Hong Kong

Far Detector

Near Detector

Ling Ao Nuclear Power Plant

Near Detector

Daya Bay Nuclear Power Plant

1 km

“We expect this to be the largest international collaboration in basic science in China and the biggest US-China collaboration.” —Yifang Wang, IHEP, Beijing

18 HUNAN JIANGXI FUJIAN angle θ13 (pronounced “theta-one-three”)—is not yet known. As long as this mixing angle is not zero, or incredibly close to zero, the Daya Bay project is poised to measure it to a level about an order of magnitude better than previous experiments, and well enough to resolve numerous mysteries of neutrinos. “Neutrinos are very hot right now,” says Brookhaven National Laboratory physicist Laurence Littenberg, a Daya Bay collaborator. “It was only in GUANGXI GUANGDONG the last decade that we learned they have mass, and there’s still so much that we don’t know about them.” Knowing the actual value of the mixing angle θ13 would help scientists understand more about neutrino behavior and possibly the early history of the universe. One of the most perplexing questions has to do with the • Canton matter we’re made of. The big bang should have created equal amounts of matter and antimatter, and they should have annihilated each other completely. Yet today, the universe still contains plenty of matter while the antimatter has disappeared. Some scientists believe that this puzzling Daya Bay phenomenon is tied to the properties of neutrinos. “At the moment, we don’t know why the universe is dominated only with matter,” Luk says. “It’s a good thing, because I don’t have to worry about shaking hands with a friend and being annihilated. It’s the reason that every- • Hong Kong one and everything exists. This is very exciting and important, and I would love to be part of the team that ﬁnds out why we are here.”

A mountainous experiment Still in the planning stage, the Daya Bay experiment would look for the third type of neutrino oscillation by studying antineutrinos, the antimatter counterparts of neutrinos. Antineutrinos are produced in nuclear reactions at power stations such as the cluster of reactors in southern China. “This Far Detector is a good opportunity to begin non-accelerator particle physics, which is not well-developed in our country,” says Wang. Groups of detectors, eight in all, each weighing 100 tons, will sit beneath granite mountains at different distances from the reactors. A set of detectors near the nuclear power stations will measure the flux and energy of the electron antineutrinos emerging from the reactors, and a set of far detectors will be positioned about 2 kilometers away. The largest fraction of electron Near Detector antineutrinos are expected to “have disappeared” at that distance, having turned into tau antineutrinos. The detectors cannot detect the tau antineutrinos, but they will measure the fraction of electron antineutrinos that did not disappear. Placed on multi-wheeled carriages, the detectors can Ling Ao be exchanged in the tunnel system to cancel systematic errors. Nuclear Described as “liquid onions,” each detector will contain three layers. In the Power Plant center will be 20 tons of organic liquid scintillator that contains gadolinium, a heavy metal. Next is a layer of liquid scintillator without gadolinium. The Near Detector outer layer uses mineral oil to act as shielding. When an antineutrino interacts with an atom inside the detector, it produces a positron and a neutron. The energy from the positron is deposited in the scintillator, which creates a burst Daya Bay Nuclear of light. About 30 microseconds later, a second burst of light is produced as Power Plant the gadolinium captures the neutron and amplifies the signal. Photomultiplier tubes that line the mineral-oil-filled outer detector tank record the light 1 km produced in this reaction. Both light flashes must be present to indicate an electron antineutrino event. In order to find a value for the mixing angle, scientists will compare the number of electron antineutrinos produced in the reactors and the number expected to arrive at each detector to how many events are actually 06 | oct/nov symmetry | volume 03 issue 08/09 detected. “Basically it comes down to how many antineutrinos disappear,” Luk says.

Strengthening ties The Daya Bay project is far from the ﬁrst physics collaboration involving both US and Chinese scientists, engineers, and technicians. The United States and China partnered with various other countries to work on the

19 “Science is getting a lot of attention in China. They are investing more and more in basic research as well as in technology.” —Kam-Biu Luk, Lawrence Berkeley National Laboratory

Beijing Electron Spectrometer (BES) and its current upgrade, BES-III, at IHEP, Beijing. Chinese physicists and technical staff work with their US counterparts on particle detector components at the CERN research laboratory in Switzerland, in preparation for experiments at the Large Hadron Collider. And the two countries will soon team up to produce particle detectors for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. “Even though the United States and China have a long history of collaboration, many people are unfamiliar with working with China and some are a little scared of doing so,” says Brookhaven’s Littenberg. “But I think Daya Bay will open those doors. Once we pioneer the techniques and establish this relationship, it will make it possible for more collaborations.” The Daya Bay experiment is the first collaboration where the countries will equally share leadership and responsibilities, possibly a sign of things to come. “The US and China have been trying to get more and more scientific exchanges between them, and this is another step in that direction,” says Randy Johnson, the US Department of Energy (DOE) program manager for the Daya Bay project. The DOE has an office in Beijing to keep track of the ever-growing activity and, in May, the National Science Foundation followed its lead. Upon opening its Beijing office, the NSF noted that China ranked fourth in the world in the year 2000 in research and development, with $48.9 billion in expenditures. Two years later, the country ranked third, behind the United States and Japan, spending an estimated $72.0 billion on R&D. “The Chinese are certainly interested and eager in science,” says the Daya Bay US project manager Bill Edwards, an engineer at Lawrence Berkeley National Laboratory. “We fight to keep the status quo in terms of funding in the US. And the Chinese seem much more willing to spend a greater portion of their budget on science than the US.” China has the Daya Bay project on a fast track, with hopes to start dig- ging the experiment’s tunnel system this spring. The Chinese Academy of Sciences has already made a financial commitment, with other Chinese funding agencies and regional governments following suit. The DOE has supplied R&D money for Daya Bay, but the project first must pass the review of its science goals before it receives further US support. Upon a successful review, the project would proceed through the “Critical Decision” stepping stones. “We passed CD-0 in the fall of 2005, and we hope to have a CD-1 review in early 2007, to evaluate the design and cost range of the project,” Edwards says. Because of a later start in the United States and the extensive scientific approval steps, full US funding isn’t expected for at least a year or two. This “phasing problem” worries some collaborators that the United States won’t be financially able to contribute within the timescale set out by the Chinese. “The Chinese don’t have the extent of project management experience that the US has,” says US Daya Bay chief scientist Steve Kettell, a Brookhaven National Laboratory physicist. “Our system is thor- ough and deliberate. It’s really phenomenal how quickly the Chinese were able to pull everything together. Now we’ve got to try to catch up.”

20 A bright future If recent events are any indication, the future scientific relationship between the United States and China looks bright. And Daya Bay would only help solidify it. Every year, the People’s Republic of China-United States Joint Committee for Cooperation in High Energy Physics meets to discuss ways to further Chinese-US cooperation in high-energy physics. “The US-PRC [effort] is a good way to promote collaboration and understanding because it continues despite any changes in government,” says Hesheng Chen, director of IHEP, Beijing. In June, the group held a special workshop in Beijing, bringing together scores of Chinese and US scientists to discuss Daya Bay and other opportunities for collaboration between the countries, including cosmic-ray studies in Tibet. Another possibility is a US-Chinese charm physics project involving the BES-III spectrometer in Beijing. The project is meant to be a continu- ation of research currently done at the CLEO experiment at the Cornell Electron Storage Ring (CESR), a more than 25-year-old facility that might soon be phased out. “Unfortunately, on CLEO we didn’t make the luminosity that we hoped for, and we weren’t able to pull off all of the measurements that we originally wanted to do,” says Rensselaer Polytechnic Institute physicist Jim Napolitano, who is spearheading the collaboration and also is involved with Daya Bay. “BES-III should have more than a factor of 10 times the intensity of CLEO, so we hope to bring our expertise there.” A group of US and IHEP scientists will meet with the NSF about the potential collaboration in November, and the DOE has already provided funding to the University of Hawaii for work on the experiment’s detector. As for Daya Bay, if the experiment passes the DOE physics review conducted in October, the project leaders hope to move through the series of critical decision steps as quickly as possible. The tentative project timeline sets construction to start in 2007, with data collection beginning in 2010. “This kind of experiment is challenging,” says Daya Bay spokesman Luk. “Having more manpower from different regions will be beneficial. The Chinese have a good site, and the US has a long history of experience in high-energy and low-energy experiments. It’s really a win-win situation.” And despite the language barriers, the time-zone differences, and the basic challenges of coordinating experiments with colleagues halfway across the world, many scientists agree that establishing a US-Chinese scientific relationship will be essential to the future of particle physics. “Whether it’s charm physics at BES-III, neutrinos at Daya Bay, or cosmic rays in the mountains of Tibet, learning how to work with China toward the goal of increasing our understanding of the world is an opportunity we can’t skip out on,” Napolitano says.

“Learning how to work with China toward the goal of increasing our understanding of the world is an opportunity we can’t skip out on.”

—Jim Napolitano, Rensselaer Polytechnic Institute 06 | oct/nov symmetry | volume 03 issue 08/09

21 T he E uropean S trategy f or P article P hysics

Recommendations approved by CERN Council establish policy for Europe to “maintain and strengthen its central position.” By Judy Jackson

23 The CERN Council’s European strategy for particle physics is available online at http://council- strategygroup.web.cern.ch/ council-strategygroup/

Image courtesy of CERN Council

At a special meeting in Lisbon on July 14, the CERN a press briefing after the Lisbon meeting. “This means Council unanimously adopted a 17-point European not thinking in terms of labs and universities, but aiming Strategy for Particle Physics, based on the premise that for global coordination and collaboration.” “Europe should maintain and strengthen its central posi- As part of the planning process, the Strategy Group tion in particle physics.” held an open forum at the Laboratoire de l’Accélerateur In its vote, the Council adopted a set of draft recom- Linéaire at Orsay, near Paris, in January 2006, to hear mendations prepared by the CERN Council Strategy from all interested members of the European particle Group, a 36-member committee created and charged by physics community. In May, they met again at DESY the CERN Council in June 2005. The statement, signed Zeuthen, near Berlin, to draft the recommendations that by all CERN member states, now has the force of a res- would be presented to the Council for adoption. olution establishing the policy for the European future In another difference from the EPP2010 process in of the field. the United States, which included European and In that respect, the European statement differs from Japanese committee members, the European Strategy a US report, Revealing the Hidden Nature of Space and Group included only Europeans. This all-European mem- Time: Charting the Course for Elementary Particle Physics, bership was dictated by the difference in the process issued earlier this year by the EPP2010 committee from the American analog, explained a member of the headed by economist Harold Shapiro. The EPP2010 doc- committee. Rather than presenting their particular pro- ument made recommendations to policy makers, while fessional or scientific points of view, members repre- the CERN statement commits the governments of CERN sented the governments of their member states, whose Council member states: it IS policy. commitment would be required in order for the draft Members of the Strategy Group stress the distinction, statement to become policy. “It’s not who wrote it that’s sometimes difficult for non-Europeans to grasp, between important,” a participant explained. “It’s who signed it.” CERN the Council and CERN the laboratory. The former However, the European process included international has responsibility for coordinating all major activities in participation. In response to formal invitations from the particle physics in Europe, including but not limited to the Strategy Group, members of the international particle management of CERN the laboratory. It is the CERN physics community, including directors of the world’s par- Council that initiated the strategic planning process and ticle physics laboratories, provided their views and per- adopted the strategy statement. spectives, and international representatives contributed to Each of the 20 CERN Council member states has two working groups during the Zeuthen “drafting” meeting. official delegates. According to the Council’s Web site, Despite differences in the European and US pro- one represents “his or her government’s administration cesses, Fermilab director Pier Oddone noted the synergy and the other national scientific interests. Each Member between the two sets of recommendations in a talk at State has a single vote and most decisions require a an International Linear Collider Workshop in Vancouver, simple majority, although in practice the Council aims for Canada in August. a consensus as close as possible to unanimity.” “There is a remarkable degree of coherence,” Oddone The Strategy Group, chaired by physicists Ken Peach of said, “which tells us that the communities across the world Oxford University and Torsten Åkesson of Lund University, agree on the future tasks of particle physics.” was born of the necessity for coordinated strategic planning A press release issued by the Council put the European at a time when the Large Hadron Collider at CERN is strategy in a global context: “The Council took the initia- about to begin operations; and when other projects, includ- tive to launch the strategy process…recognising that the ing the proposed International Linear Collider, are under LHC is a unique facility for the world’s particle physicists, consideration. The European Strategy defines how Europe and considering that this was the right time to address the will address these and other programs and initiatives. issue of how European particle physics will engage with “We need to secure European leadership in particle other regions of the world to develop the next generation physics,” said CERN Council president Enzo Iarocci at of particle physics facilities.”

24 The European strategy for particle physics Particle physics stands on the threshold of a new and exciting era of discovery. The next generation of experiments will explore new domains and probe the deep structure of space-time. They will measure the properties of the elementary constituents of matter and their interactions with unprecedented accuracy, and they will uncover new phenomena such as the Higgs boson or new forms of matter. Longstanding puzzles such as the origin of mass, the matter-antimatter asymmetry of the Universe and the mysterious dark matter and energy that permeate the cosmos will soon beneﬁt from the insights that new measurements will bring. Together, the results will have a profound impact on the way we see our Universe; European particle physics should thoroughly exploit its current exciting and diverse research programme. It should position itself to stand ready to address the challenges that will emerge from exploration of the new frontier, and it should participate fully in an increasingly global adventure.

General issues Organizational issues 1. European particle physics is founded on strong national institutes, 11. There is a fundamental need for an ongoing process to define and universities and laboratories and the CERN Organization; Europe should update the European strategy for particle physics; Council, under Article maintain and strengthen its central position in particle physics. II-2(b) of the CERN Convention, shall assume this responsibility, acting as a council for European particle physics, holding a special session at least 2. Increased globalization, concentration and scale of particle physics once each year for this purpose. Council will define and update the strategy make a well coordinated strategy in Europe paramount; this strategy will based on proposals and observations from a dedicated scientific body be defined and updated by CERN Council as outlined below. that it shall establish for this purpose.

12. Future major facilities in Europe and elsewhere require collabora- Scientific activities tions on a global scale; Council, drawing on the European experience in 3. The LHC will be the energy frontier machine for the foreseeable future, the successful construction and operation of large-scale facilities, will maintaining European leadership in the field; the highest priority is to prepare a framework for Europe to engage with the other regions of the fully exploit the physics potential of the LHC, resources for completion world with the goal of optimizing the particle physics output through of the initial programme have to be secured such that machine and the best shared use of resources while maintaining European capabilities. experiments can operate optimally at their design performance. A subse- 13. Through its programmes, the European Union establishes in a broad quent major luminosity upgrade (SLHC), motivated by physics results sense the European Research Area with European particle physics having and operation experience, will be enabled by focussed R&D; to this end, its own established structures and organizations; there is a need to R&D for machine and detectors has to be vigorously pursued now and strengthen this relationship for communicating issues related to the strategy. centrally organized towards a luminosity upgrade by around 2015. 14. Particle physicists in the non-Member States benefit from, and add 4. In order to be in the position to push the energy and luminosity frontier to, the research programme funded by the CERN Member States; even further it is vital to strengthen the advanced accelerator R&D pro- Council will establish how the non-Member States should be involved in gramme; a coordinated programme should be intensified, to develop the defining the strategy. CLIC technology and high performance magnets for future accelerators, and to play a significant role in the study and development of a high- intensity neutrino facility. Complementary issues 5. It is fundamental to complement the results of the LHC with measure- 15. Fundamental physics impacts both scientific and philosophical thinking, ments at a linear collider. In the energy range of 0.5 to 1 TeV, the ILC, based influencing the way we perceive the universe and our role in it. It is an on superconducting technology, will provide a unique scientific opportunity integral part of particle physics research to share the wonders of our dis- at the precision frontier; there should be a strong well-coordinated coveries with the public and the youth in particular. Outreach should be European activity, including CERN, through the Global Design Effort, for its implemented with adequate resources from the start of any major project; design and technical preparation towards the construction decision, to be Council will establish a network of closely cooperating professional com-

ready for a new assessment by Council around 2010. munication officers from each Member state, which would incorporate 06 | oct/nov symmetry | volume 03 issue 08/09 existing activities, propose, implement and monitor a European particle 6. Studies of the scientific case for future neutrino facilities and the R&D physics communication and education strategy, and report on a regular into associated technologies are required to be in a position to define the basis to Council. optimal neutrino programme based on the information available in around 2012; Council will play an active role in promoting a coordinated European 16. Technology developed for nuclear and particle physics research has participation in a global neutrino programme. made and is making a lasting impact on society in areas such as material sciences and biology (e.g. synchrotron radiation facilities), communication 7. A range of very important non-accelerator experiments take place at and information technology (e.g. the web and grid computing), health (e.g. the overlap between particle and astroparticle physics exploring other- the PET scanner and hadron therapy facilities); to further promote the wise inaccessible phenomena; Council will seek to work with ApPEC to impact of the spin-offs of particle physics research, the relevant technology develop a coordinated strategy in these areas of mutual interest. transfer representatives at CERN and in Member states should create a 8. Flavour physics and precision measurements at the high-luminosity technology transfer forum to analyse the keys to the success in technology frontier at lower energies complement our understanding of particle physics transfer projects in general, make proposals for improving its effectiveness, and allow for a more accurate interpretation of the results at the high- promoting knowledge transfer through mobility of scientists and engineers energy frontier; these should be led by national or regional collaborations, between industry and research. and the participation of European laboratories and institutes should be 17. The technical advances necessary for particle physics both benefit promoted. from, and stimulate, the technological competences available in European 9. A variety of important research lines are at the interface between par- industry; Council will consolidate and reinforce this connection, by ensur- ticle and nuclear physics requiring dedicated experiments; Council will ing that future engagement with industry takes account of current best seek to work with NuPECC in areas of mutual interest, and maintain the practices, and continuously profits from the accumulated experience. capability to perform fixed target experiments at CERN.

10. European theoretical physics has played a crucial role in shaping and Source: The European strategy for particle physics, CERN Council, 2006. consolidating the Standard Model and in formulating possible scenarios for future discoveries. Strong theoretical research and close collaboration with experimentalists are essential to the advancement of particle physics and to take full advantage of experimental progress; the forthcoming LHC results will open new opportunities for theoretical developments, and create new needs for theoretical calculations, which should be widely supported.

25 deconstruction: ILC cryogenics

charged particles by transferring energy from electromagnetic Cavities propel waves to the particles, speeding them up. Superconducting cavities are made of material that can conduct electric currents without resistance at a very low temperature. To cool such a cavity close to absolute zero, engineers design cryogenic vessels that submerge cavities in a bath of liquid helium. The proposed International Linear Collider will use 16,000 superconducting cavities made of niobium, and scientists around the world are working on the cryogenic system needed to keep the cavities cool.

7 7

4 4 3

3 5

Vacuum—air at greatly reduced pressure—is a great insulator, Liquid nitrogen keeps the temperature of the copper shield at conducting much less heat than air at normal pressure. This 80 K. The nitrogen ﬂows through a thin pipe that winds around cryogenic vessel operates at a vacuum of 15 torr, a pressure the copper structure. Since copper is a good heat conductor, about 50 times lower than normal atmospheric pressure. only a few windings are necessary to carry away excess heat.

Up to 40 layers of aluminized Mylar ﬁlm, a material also used for helium balloons, cover the copper shield and the titanium cylinder. The resulting blanket, known as superinsulation, reﬂects heat transferred in the form of infrared radiation.

26 1 2

This cryogenic vessel, used for testing, cools a single ILC Protecting the inner, coldest part of the cryogenic vessel from cavity to 1.8 Kelvin, or minus 456 degrees Fahrenheit. The heat are three shells separated by vacuum. The outer shell cavity, about three feet long, sits in a cylinder ﬁlled with liquid of the vessel, made of stainless steel, is at room temperature, or helium (LHe), which keeps the cavity ultracold. A steady about 300 K. The innermost shell of the vessel, made of tita- stream of liquid helium enters the cylinder from below and nium, is at 1.8 K, the temperature of the liquid helium coolant. An exits it at the top, carrying away excess heat. As the helium intermediate shell, dubbed the copper shield, reduces the heat absorbs heat, some of the liquid evaporates and turns into ﬂow between the outer and inner shells. The shield is cooled gas (GHe), rising to the top. Together with warmed-up liquid to 80 K. The vacuum between the shells reduces the transfer of helium, the gas returns to a cryogenic system that cools the heat due to air and helium gas inside the cryogenic vessel. helium back to 1.8 K.

1 2

7 7

6 7

When cooling the cavity from room temperature to 1.8 K, the Electromagnetic waves accelerate a particle beam straight length of the cavity shrinks by a few millimeters. Yet the exact through the center of the cavity. To produce the best particle positioning of each cavity is extremely important to make an acceleration, the interior surface of the cavity must be highly accelerator with thousands of cavities work. A ﬁberglass rod, polished and without impurities. Pumps remove the air from which ﬁts precisely into a hole at the bottom of the titanium interior of the cavity to keep the surface clean and to minimize cylinder while conducting almost no heat, allows for positioning the scattering of the beam by air molecules. The vacuum in- 06 | oct/nov symmetry | volume 03 issue 08/09 the cavity with greatest accuracy. side the cavity has a pressure of only a millionth of a millitorr.

Text: Kurt Riesselmann Graphic: Michael McGee and Dirk Hurd, Fermilab

27 gallery: quark park Science in the Park

Photos by Elle Starkman, above and bottom right Stellarator Princeton Plasma Physics Laboratory Aluminum tubing, styrofoam Text by Patti Wieser, Artist: Rein Triefeldt Princeton Plasma Physics Laboratory Scientist: Rob Goldston, Plasma Physics

This 16-foot structure represents an experimental fusion device called a stellarator, or star generator. The bright pink styrofoam sculpture has the cruller-doughnut shape of the plasma to be produced by the National Compact Stellarator Experiment (NCSX), scheduled to begin operation in 2009. Pink depicts the color of the plasma—the hot, ionized gas used as fusion fuel—although fusion plasmas would be most visible to those able to see X-rays.

28 here’s a new scientific path in Princeton, T New Jersey. Out of the loam of a vacant lot, a cluster of quasicrystals winks at some pink plasma. Tectonic plates shift, and neurons connect in a hippocampus curve of bamboo. In one corner, colorful cells that detect and transmit smells to the brain sparkle in the sunlight. Quark Park is a new—though temporary— 15,000-square-foot sculpture garden. Its art and plantings reflect research in fusion energy, mountain range formation, robotics, neuroscience, and other areas of science. Alan Goodheart, Peter Soderman, and Kevin Wilkes, who conceived, designed, and organized Quark Park, sum up the garden as a celebration of “the mysteries of science and art, and the contributions of Princeton area scientists and designers.” In 2004, the trio developed the award-winning Writers Block at the same loca- tion, a concept that brought together writers and designers. “We want the visitors of the park to have a moment of enjoyment, a glimpse of beauty, and a sense of the dimensions of contemporary science,” says Wilkes, a Princeton architect. “We want all members of the public, children of all ages, people of all ethnicities, to be able to find a moment of delight and hope in this park. We want children to connect to the realm of science in a way that is fascinating and intriguing without having to resort to a blackboard and a textbook.”

a b o v e The Weather Garden Birch trees, stained glass, bamboo, sun, wind, rain

Artists: Holly Grace Nelson and Matt Kiefer Scientist: George Philander, Geosciences

Weather, always difﬁcult to predict, is a chaotic system. To cre- 06 | oct/nov symmetry | volume 03 issue 08/09 ate order and understanding, scientists pose selective questions and answer them in idealized contexts. The Weather Garden represents this approach, featuring an orderly sun garden (photo), a path under raining arches, and a cloud garden with a fog system. An oculus ﬁlled with stained glass symbolizes the sun. “A true gardener acknowledges nature’s constraints and within them creates an island of order in a sea of disorder,” says Philander.

29 gallery: quark park

l e f t Augmented Lithophone Granite, steel, microphones, loudspeakers

Artist: Jonathan Shor Scientist: Perry Cook, Computer Science and Psychoacoustics

This lithophone sculpture is made of 17 resonant granite columns that ring when struck, resembling a stone xylophone. A piezoelectric contact microphone at each “bar” transfers the vibrations to a box containing digital signal processing equipment, which adds delays and re- verb to the sounds and simulates a cave- like environment. Viewers are invited to “play” the lithophone by striking the granite posts. Cook composed a musical rendition of Shor splitting stone; a re- cording of the piece is played constantly around the sculpture.

More than a dozen well-known scientists participated in the project, including Shirley Tilghman, molecular biolo- gist and president of Princeton University; Rush Holt, physicist and US Representative from New Jersey’s 12th Congressional District; Freeman Dyson, scientist and author; Paul Steinhardt, theoretical physicist; and Rob Goldston, director of the Princeton Plasma Physics Laboratory. They served as the artists’ muses, and the collaborations have yielded a stunning collision of art, archi- tecture, and landscaping that reﬂect scientiﬁc concepts. The garden paths form a labyrinth, shaded by cano- pies of aluminum, wood, and plants. At the center is the Inner Circle, an urban piazza that serves as the locus of parties, receptions, dances, and tours of the garden, as well as a place for people to pause and chat. Quark Park’s grand opening was September 8. Open to the public and for community events, the garden will operate through Thanksgiving. Once it closes, each installation belongs to the artist, who may keep, sell, or donate his or her piece.

More information about Quark Park and the scientist-artist teams is at www.princetonoccasion.org/quarkpark/

l e f t Sensation: Interior View Multi-colored cast resin discs, steel, wires

Artist: Nancy Cohen with help from James Sturm, Electrical Engineering Scientist: Shirley Tilghman, Molecular Biology

Discussions with Tilghman about research in molecular biology, in particular the Nobel Prize-winning research by Richard Axel and Linda Buck, inspired this installation. The sculpture symbolizes how odors are recognized and remembered. The multi-colored discs represent the neurons in the nose that detect different odorant molecules, and the wires correspond to the axonal connections that pass through the skull to the olfactory bulb in the brain. The wires light up, and each color indicates the response to a different odor.

30 l e f t Hippocampus Bamboo, concrete, ﬁberglass, steel

Artists: Steve Weiss and Dolph Geurds Scientist: Tracey Shors, Neuroscience

Shors’ research focuses on understanding how memories are formed and stored in the brain. She says that brains, especially neuron projections called dendrites and nerve ﬁbers known as axons, resem- ble tree branches. Hippocampus symbolizes the area of the brain that plays a part in learning. Geurds and his staff placed tall bamboo in concrete, creating a hippocampus-like shape. Weiss created two 30-inch-tall masks of cement reinforced with ﬁberglass and steel that represent a man and a woman. Boxwood tree roots shooting out of the mask tops mimic branching dendrites in the brain.

r i g h t t o p Sundial Steel, wood

Artist: Allan Kehrt Scientists: Freeman Dyson and Rush Holt, Physics

Architect Kehrt teamed up with Dyson, professor emeritus at the Institute for Advanced Study, and US Representative Holt, former assistant director of the DOE Princeton Plasma Physics Laboratory. His installation, a vibrant wood shadow maker set on an 800-pound steel base, is about the sun, fusion, and nuclear energy. The chili-pepper-red gnomon soars above nearby cornstalks and casts a shadow on a ﬂat panel marked with the day’s hours.

right center Motion in the Ocean Material: Glass, wood

Artist: Robert Kuster Scientist: Naomi Ehrich Leonard, Mechanical and Aerospace Engineering

Leonard’s research focuses on feedback—the responsive behavior of groups. She uses mathematical concepts of synchrony and interconnection to model and analyze natural collectives, and to design robotic collectives. Motion in the Ocean contains 2000 clear blown-glass bubbles ranging from 5 to 10 inches in diameter, a school of 25 glass fish, and a fleet of four glass robotic underwater gliders. The bubbles create the underwater world. The schooling fish and gliders are reminis- cent of a well-choreographed dance of animals—or robots—that move as a group. Individual animals respond to the motion of others nearby, representing the concept of feedback.

right bottom Forbidden Geometry Indiana limestone, granite, glass

Artist: Christoph Spath 06 | oct/nov symmetry | volume 03 issue 08/09 Scientist: Paul J. Steinhardt, Physics

Quasicrystals are a new class of materials whose atomic arrangements exhibit symmetries that do not fit the definition of crystals. Correspondingly, quasicrystals have physical properties different from crystals. One “forbidden” geometry observed in quasicrystals is the five-fold symmetry, depicted in this installation. Says Steinhardt, “The sculpture shows a cluster with four types of interlocking units that could be continued to fill Quark Park and beyond in a pattern with icosahedral symmetry.”

31 essay: joe willie

Photo courtesy of Joe Willie Ken Cecire,Education Specialist andQuarkNet flares, known for disrupting telecommunications. analyze it. andmy studentsandIwould download thedata hour.muon ratesevery Onceamonth,Iwould my classroomandprogrammed ittomeasure rays, my new students and I placed a detector in 2002. To conductlong-termstudiesofcosmic activity, andtimeofday. muon rates and barometric pressure, geomagnetic discovering connectionsbetween cosmic-ray experiments, own their ran and time” “detector for up signed They hypotheses. own their on sunnydays. muons strikethegroundoncloudydaysthan fewer that example, for We found, rays. cosmic recorded and sky the in points numerous at another teacher, we pointed the muon telescope a deviceIbuilt,dubbedthe“Willie Wheel” by paddle-shaped telescopeto“mapthesky.” Using fall, my physics students and I began to use my space. from Earth the hitting muons) (mainly particles charged instead of light, the instrument detects high-speed telescope; optical an to resemblance faint a only bears telescope muon a that discovered also I electron. the of version unstable heavier, me. to appealed immediately idea The use. classroom for telescope muon a building involved that teachers science school high It announcedathree-weeksummerinstitutefor 2000. of spring the in QuarkNet called gram pro outreach an about Rochester of University between cosmicraysandsolarflares? become ahotspotformonitoringthecorrelation NewYorkHow doesahighschool inupstate problem The solarflare In October 2003, scientists reported large solar in School High Mendon Pittsford to moved I I challenged mystudentstopropose andtest When that Ireturned toNaplesHighSchool a is muon a that learned I summer, That the from flier a to back goes story The

32 particle a hosts university the spring, Each program. ( Experiments Classroom Inventing director of the Physicists And Rochester Teachers and Rochester of University the at professor physics McFarland, mentor,Kevin QuarkNet a significantresourceforcosmic-raystudies. become had program Research Muon Mendon Storm;”Irealizedthatthe the “HalloweenSolar rates following a flare that my students dubbed muon in decrease dramatic a showed data Our graphs of our data to schools around the world. the flares. had operatedamuondetector atthetimeof includes hundreds of schools in several countries, if anyoneintheQuarkNet community, which activity wouldbeoncosmic-rayrates.Heasked ple werespeculatingwhattheeffect ofsolar to all QuarkNet teachers an email in which peo staff teacher from Hampton University, forwarded Office of Science of the Department of Energy. QuarkNet is funded by the National Science Foundation and the affiliated with QuarkNet, is at www.pas.rochester.edu/particle/. Information on affected by the highly variable weather in upstate New York. Bristol Mountain or tending to his garden, which he notes is also When not chasing cosmic rays, he can be found skiing down School. High Mendon Pittsford at physics teaches Willie Joe Joe Willie discovery. next our to forward looking I’m and significant contributions to cosmic ray research, complex, technological world. help them meet the challenges of an increasingly vides students with skills and insights that will demystifies modernscientificresearch andpro close-ended goals, never can. I feel our project and instructions “cookbook” using labs, school high traditional that way a in research real dents experience the thrills and agonies of doing minutes. five every Internet the on rates muon posts now system automated our capability, detection our in increase 100-fold a of Because operation. began detector the 2004, of fall the In data. of stream huge a such process to calling engineersatFermilab tofigureouthow frequently detector, new the for gramming acquisitionpro Melville, tookcharge ofthedata the “motherofallpaddles.” Onestudent, Jeff high school teachers tobuildthisnewdetector, withagroupofotherstudentsand laborated an oldFermilab experiment. detector from usingmaterialthathecouldobtain McFarland encouraged us to build a larger muon My students presented their results to my my to results their presented students My sending were I and students my days Within I amthrilledthatmystudentsandhavemade My greatestsatisfactionistoseemystu col students my of year, two Thefollowing conference. Impressed by our results, results, our by Impressed conference. particle , the University of Rochester program

particle -

) ) - - - -

symmetry | volume 03 | issue 08/09 | oct/nov 06 logbook: cosmic microwave background

of the early universe implies that the universe is The big-bang theory immersed in a bath of microwave light, a cooled- down remnant of early high-temperature radiation, invisible to the naked eye. In 1964, Arno Penzias and Robert Wilson first observed this microwave radiation, giving credibility to the big- bang scenario. On November 18, 1989, NASA launched the Cosmic Background Explorer (COBE) satellite to measure the microwave radiation across the sky. The first results arrived quickly. Based on a mere nine minutes of observing data, one of the COBE instruments produced the detailed “blackbody” spectrum predicted by cosmologists, reinforcing the validity of the big-bang theory. NASA’s John Mather led the team of scientists working on the instrument on board of COBE that measured the microwave spectrum. He presented this chart in January 1990, at a meeting of the American Astronomical Society, receiving a standing ovation. The result ushered in a new era of precision cosmological measurements, and Mather received the 2006 Nobel Prize in Physics. George Smoot, of the US Department of Energy’s Lawrence Berkeley National Laboratory, is the co-recipient of the 2006 Nobel Prize. He led the collaboration operating the second main instrument on COBE, which measured tiny fluctuations in the cosmic microwave background spectrum coming from different directions, just as has been predicted by theory. David Harris

Graphic courtesy of NASA explain it in 60 seconds

(electrons, protons, and other charged parti- Acceleration of particles cles) is achieved by propelling them with electromagnetic waves. The energy of the waves is transferred to the particles as the particles travel through special cavities made of copper or superconducting material. To understand how this works, imagine a surfer riding a wave. If the surfer paddles at the right speed and gets on a wave at the right time, the surfer will be accelerated to the speed of the wave. If the initial speed of the surfer is wrong, the wave will just pass the surfer by; if the timing is wrong, the surfer will lose speed. An electron traveling through a cavity “ﬁlled” with radio-frequency waves acts very similarly. If the particle enters the cavity at the right time, it will gain energy from the wave. If it arrives at the wrong time, it will gain less energy, be decelerated, or be lost. In a particle accelerator, particles travel through multiple cavities to go from low speed to almost the speed of light. The trick is to tune the cavities so that the waves are in sync with the particles and provide maximum acceleration at each point along the accelerator. Andrew Hutton, Jefferson Lab

Symmetry A joint Fermilab/SLAC publication PO Box 500 MS 206 Batavia Illinois 60510 symmetryUSA

Ofﬁce of Science U.S. Department of Energy