dimensions volume 04 particle A joint Fermilab/SLAC ... · B factory—a particle collider that generates large numbers of b mesons—and a light source. They will be joined next

september 07

issue 07

volume 04dimensionsof particle physicssymmetry

A joint Fermilab/SLAC publication

dimensionsof particle physicssymmetry

A joint Fermilab/SLAC publication

volume 04 | issue 07 | september 07

On the coverThis month, art and science meet in our story on the posters of particle physics. For more than 30 years, the trademark black and white posters of Angela Gonzales announced every major event, conference and workshop at Fermilab. The onion, at left, from a poster for a 1977 conference on “Parity Nonconservation, Weak Neutral Currents and Gauge Theories,” symbolizes the many layers of particle physics as it penetrates deeper and deeper into the fundamental nature of the physical universe. Inside front coverFermilab artist Angela Gonzales used reflected images of the laboratory’s signature prairie plants and Wilson Hall to symbolize matter and antimatter for a 1988 conference on “Proton-Antiproton Collider Physics.”

Office of ScienceU.S. Department of Energy

02 Editorial The world of particle physics is in a period of

great change. The laboratories are approaching the future in different ways, determined by their individual circumstances.

03 Commentary: Philip Burrows We can all do our parts to engage with our

local politicians, funding agencies, compa-nies, colleagues, relatives, and friends. Make good use of Gateway to the Quantum Universe and help get the message out.

04 Signal to Background Plugging an artsy roof; Fermilab’s fluttering

comma; nature’s particle bounty; the no-muss, no-fuss instant computing center; BaBar ’s six minutes of fame; nightclub physics; particle contest winners.

10 Fermilab’s Path to the Future A new report gives top priority to developing

the International Linear Collider, while laying out a plan for science that could be done along the way.

16 The End of the HERA Era Celebration, anticipation, and a little wistful

reflection: The final shift of the HERA accelerator brought more than 1000 people to Hamburg for a last hurrah.

24 The Art of the Unseen As technology evolves, posters are easier

to produce and pass around. But it still takes skill and imagination to illustrate the most abstract ideas of physics.

30 Day in the Life: HERAfest When 1800 people gathered to celebrate

the last days of a fabled collider, the crowd included Greek gods and goddesses and a giant bottle of steak sauce.

32 Gallery: Amy Lee Segami With an ancient art that involves floating

inks on water, an engineer captures the intricate swirls of nature.

36 Essay: Barbara Manning “Today, I am older, tire easily, and have grown

too large to crawl inside a computer system and fix it. Just as well; today’s computers are too small for that.”

ibc Logbook: HERA Start-up On October 19, 1991, at 6:50 p.m., Bjørn

Wiik logged the first collisions in the new electron-proton particle collider at the Deutsches Elektronen-Synchrotron in Hamburg.

bc Explain it in 60 Seconds: Theory A theory, in everyday language, differs little

from a guess or a hunch. But in science we reserve the word for a well-developed idea based on experimental evidence.

2

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

The challenge of changeThe world of particle physics is changing. In a few years’ time, most large particle colliders will have closed; the only one left operating will be the Large Hadron Collider at CERN outside Geneva, Switzerland. Although plans are under way for future facilities to address compelling scientific questions, nothing is set in stone, and start dates will depend as much on political factors as on scientific and technical ones.

Laboratories are approaching the future in different ways, determined by their individual circumstances.

The German laboratory DESY has just closed its proton-electron collider, HERA (see page 16). Even so, DESY sees a future strongly engaged in parti-cle physics. DESY scientists will collaborate in LHC experiments and continue to play leading roles in the International Linear Collider. DESY will also play a major role in photon science through the FLASH X-ray light source.

Change is also on the way at Japan’s KEK laboratory, which operates a B factory—a particle collider that generates large numbers of b mesons—and a light source. They will be joined next year by a new high-intensity proton accelerator at the J-PARC research complex. With the B-factory approaching its initial goal for data collection, KEK too will enter a new phase and will soon have to decide on its roadmap.

In the US, the Tevatron Collider at Fermi National Accelerator Laboratory and PEP-II at Stanford Linear Accelerator Center will shut down in the next few years.

SLAC will retain an active particle physics effort, including participation in the ATLAS experiment at the LHC and research and development for the ILC. It’s also expanding its photon science program with the Linac Coherent Light Source, which will use intense X-rays to probe materials, chemistry, physics and the workings of living things.

Fermilab confronts a challenging future. As a single-purpose laboratory dedicated to particle physics, its work has centered on the Tevatron. The lab is heavily involved in the LHC, has a strong program in particle astro-physics and is committed to making the ILC happen, as well as host it. But in the event that international political negotiations delay the ILC, Fermilab has proposed a plan (see page 10) to ensure a healthy future.

There is uncertainty ahead, but scientists are used to dealing with chal-lenges. The plans in place for particle physics laboratories promise exciting and productive years ahead.David Harris, Editor-in-chief

from the editor

symmetry

SymmetryPO Box 500MS 206Batavia Illinois 60510USA

630 840 3351 telephone630 840 8780 [email protected] (c) 2007 symmetry All rights reserved

symmetry (ISSN 1931-8367) is published 10 times per year by Fermi National Accelerator Laboratory and Stanford Linear Accelerator Center, funded by the US Department of Energy Office of Science.

Editor-in-ChiefDavid Harris650 926 8580

Deputy EditorGlennda Chui

Managing EditorKurt Riesselmann

Senior EditorTona Kunz

Staff WritersElizabeth ClementsHeather Rock Woods Kelen Tuttle Rhianna Wisniewski

Copy Editor Melinda Lee

InternsKen KingeryAmelia Williamson

PublishersNeil Calder, SLACJudy Jackson, FNAL

Contributing EditorsRoberta Antolini, LNGSPeter Barratt, STFC Romeo Bassoli, INFNStefano Bianco, LNFKandice Carter, JLabReid Edwards, LBNLSuraiya Farukhi, ANLJames Gillies, CERNSilvia Giromini, LNFYouhei Morita, KEKMarcello Pavan, TRIUMFPerrine Royole-Degieux, IN2P3 Yuri Ryabov, IHEP ProtvinoYves Sacquin, CEA-SaclayKendra Snyder, BNLBoris Starchenko, JINRMaury Tigner, LEPP Ute Wilhelmsen, DESYTongzhou Xu, IHEP BeijingGabby Zegers, NIKHEF

Print Design and ProductionSandbox StudioChicago, Illinois

Art DirectorMichael Branigan

DesignersAaron Grant Anilou Price

Web Design and ProductionXeno MediaHinsdale, Illinois

Web ArchitectKevin Munday

Web DesignKaren Acklin Alex Tarasiewicz

Web ProgrammerMike Acklin

Photographic Services Fermilab Visual Media Services

Pho

to: B

arba

ra W

arm

bein

, DES

Y

3

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

commentary: philip burrows

An engaging new way to get the message outIn August, the International Linear Collider reached an important milestone when two huge docu-ments were presented to the international particle physics com-

munity at a meeting in Daegu, Korea.The Reference Design Report and Detector

Concepts Report total four volumes and hundreds of pages. They describe, in scientific and techni-cal detail, potential for discovery with the ILC, the state of the design, and current thinking about how particle detectors could be laid out. More than 1500 scientists and engineers from around the globe contributed to the work that is documented in these reports. The detailed R&D, engineering, and design work comes together from many laboratories and universities around the world, all of them invested in making the ILC a reality.

Just as significant is a “companion docu-ment” presented at the same meeting of the International Committee on Future Accelerators in Daegu. A slender 38 pages, The International Linear Collider: Gateway to the Quantum Universe is less imposing. Prepared by a dedicated com-mittee over the past one and a half years, it also documents the work of the global ILC team, but with less emphasis on the technical details. That’s because Gateway is intended primarily for an audience outside the particle physics com-munity. It represents our attempt to distill the ILC science goals, the key features of the collider and detector designs, and the technological challenges, and put them in an accessible and easy-to-read format.

Gateway is written for government decision-makers, including elected representatives and administration officials who help set science policy; representatives of the businesses and industries that will ultimately produce the myriad components of the collider; scientists outside particle physics; educators at universities, col-leges, and high schools; and interested members of the public, on whose behalf we are pursuing the physics of the Terascale.

Considering these audiences, and mindful of the fact that they live in a number of different countries, we have tried to make Gateway to the

Quantum Universe attractive, approachable, and fun. Our hope is that readers can absorb the report in the time it takes to make a short journey by plane or train, aided by the many illustrations inside. We shall distribute copies this autumn through our international funding agencies, lab-oratories, universities, and national communities, and the document will also be presented via an attractive Web site.

Now that the Reference Design Report is fin-ished, the ILC needs to change gears. We need to broaden our communications horizon beyond “internal” publications—such as ILC NewsLine, with its news, features, and weekly updates—to include a more diverse audience.

The assembly and honing of Gateway by 20 representatives of the global ILC community was the easy part. The next stage will require help from all of us who care about the future of particle physics.

We have an exciting science case and a com-pelling roadmap for the scientific journey that will lead us to uncover the mysteries of the Teras-cale. The first milestone will be the start of the Large Hadron Collider at CERN in 2008. We are all keen to see the discoveries that will surely be made there. The ILC will be our next major milestone, and we need to prepare for it and make it happen. We can all do our parts to engage with our local politicians, funding agencies, com-panies, colleagues, relatives, and friends. Make good use of Gateway to the Quantum Universe and help get the message out.Philip Burrows

Philip Burrows is a professor in the John Adams Institute for Accelerator Science at Oxford University. He served as chair of the Gateway to the Quantum Universe committee.

Pho

to c

ourte

sy o

f Phi

lip B

urro

ws

4

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

signal to background

The roof that would not seal; Fermilab’s fluttering comma; nature’s particle

bounty; the no-muss, no-fuss instant computing center; BaBar’s six minutes of

fame; nightclub physics; particle contest winners.

From rivets to ribbitsAn impromptu frog habitat van-ished with final repairs to the roof of Fermilab’s Meson Lab.

Leaks—lots of leaks—have plagued the lab’s 12 blue and orange concave arches since it opened 32 years ago. The building was created as a strik-ing aesthetic element of the Fermilab landscape, but the nearly 44,000 rivet holes pro-vided 44,000 possible places for water to find a way inside.

“This roof is notorious. It has challenged every director the lab has had,” says Erik Ramberg, head of the Meson test facility. “We’ll see if this one triumphs.”

The leaks forced scientists to move equipment, build indoor roofs four layers thick to pro-tect machinery, and even shut down parts of experiments.

Amphibians, meanwhile, were in heaven.

Ramberg says that in his five years working in the lab, he often heard croaking. “I saw a snake in there yesterday,” he says. “It has to be eating something.”

Workers recently took to the roof to patch holes in the steel and fill in cavities. Then they applied an elastomeric coating that hardened in the sunlight to form a flexible sheet. Finally, they restored the building’s original blue and orange colors.

Ramberg says he’ll miss the building’s quirks, such as the rain that would fall indoors the day after a snowfall. But he hopes the repairs stick, for both safety and financial reasons.

The building will soon become home to R&D projects for the proposed International Linear Collider. “This is a big milestone for us, because that facility will become a showcase for the laboratory over the next few years,” says Randy Ortgiesen, head of the lab’s Facilities Engineering Services Section. “We’ll have dignitaries coming from all over to tour it.”Rhianna Wisniewski

Pho

to: R

eida

r Hah

n, F

erm

ilab

5

Butterfly researchers come to Fermilab for rare speciesScientists usually search Fermilab for exotic particles, but two Alabama researchers recently sought another rarity—a butterfly called the Gray Comma.

The woodland butterfly with the comma-shaped marking under its wing was one of the last 10 butterfly species Paulette Haywood and Sara Bright needed to complete a book about the 125 butterfly species of the Southeastern United States. The pair has worked on the book for 12 years.

“The Gray Comma would have been difficult to find and docu-ment in the Southeast,” says Haywood. “So for us to be able to come to Fermilab and knock another species off our list was huge.”

The researchers were drawn to the laboratory by a Web site, run by Technical Division engi-neer Tom Peterson, that docu-ments Fermilab’s natural setting and its butterfly population.

Peterson, who has watched butterflies at Fermilab for 31 years, was happy to point out the butterfly’s habitat on the west side of the laboratory. “We’ve been careful, in our man-agement of the land here at Fermilab, to restore it in a way that’s friendly to nature,” he says. “And certainly that’s reflected in the variety of but-terflies, birds, and plants we find here.”

Haywood and Bright hope their book will help people understand how interconnected nature is and the importance of taking care of the environ-ment. “People love to look at beautiful butterflies,” Haywood says. “But they have to under-stand that to see those beauti-ful butterflies, there have to be places like Fermilab for them to live and thrive.”Amelia Williamson

Particles in the skyWhat is the universe made of? What are matter, energy, space, and time? How did we get here and where are we going?

In particle physics, the clas-sic place to look for answers is in giant accelerators where particles collide.

But nature also provides a wealth of data, in the form of neutrinos streaming from the sun and other stars, the faint afterglow of radiation from the big bang, and other space phe-nomena. Particle physicists increasingly turn to these non-traditional sources of infor-mation and collaborate with colleagues in astrophysics and cosmology to get a more complete view.

That collaboration is reflected in the spires database of pub-lications in high-energy phys-ics. Starting in the 1980s, large numbers of particle physi-cists began citing articles related to the sky. For much of that decade, two publications on the theory of inflation, the super-fast expansion of the early universe, ranked among the 50 most-cited papers in spires.

By the late 1980s, neutrino data gleaned by observing the

sky became a hot commodity. Interest was spurred by the first recordings of neutrinos emitted by a supernova, or exploding star, obtained by the Kamiokande-II and Irvine-Michigan-Brookhaven experi-ments. A few years later, parti-cle physicists eagerly absorbed results from the Cosmic Background Observer, a satel-lite that mapped the afterglow of the big bang; the announce-ment of those results was the second-most-cited publication in the spires database for 1993.

The last ten years have seen a flood of non-traditional papers on the spires top- cited lists (see www.slac.stan-ford.edu/spires/topcites/matrix.shtml). They include the discovery of oscillations of atmospheric neutrinos, evidence for an accelerating universe, and the puzzling deficit of cer-tain types of neutrinos from the sun. Together, the contribu-tions from all of these fields bring us closer to understand-ing the mysteries of the universe.Heath O’Connell

Illus

tratio

n: S

andb

ox S

tudi

o

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

6

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

signal to background

Computing center in a boxStanford Linear Accelerator Center’s newest computing center arrived in a standard 20-foot-long shipping container.

But nobody had to worry about pulling a muscle unpack-ing it. A crane lifted the 23,340 pound container off a flatbed truck and carefully placed it on a concrete pad behind the computing building.

Once hooked up to power, cooling water, and networking cables, it became a self-con-tained data center with 252 servers, expanding the lab’s scientific computing capacity by one-third.

SLAC is the first customer to test Sun Microsystems’ self-contained computer cen-ter, known as Project Blackbox. Randy Melen, leader of the lab’s high-performance storage and computing team, says it was the answer to the question, “How do you extend your data center without too much pain?”

Doors at each end of the insulated shipping container open onto a center aisle that

looks like a hall of mirrors, lined with shiny silver panels. Racks of computing equipment are hidden behind the panels and can be pulled out into the aisle for maintenance.

One thing: SLAC’s Blackbox is not black. It was painted white, to stay cooler in the California sun.Heather Rock Woods

BaBar is a video starSearch for “BaBar” on YouTube.com, and you’ll get a long list of links to a 1980s TV series based on an animated elephant. But a surprise is hid-den among the cartoons—a six-minute film shot in the Stanford Linear Accelerator Center’s BaBar control room.

The film was created by University of Tennessee grad-uate student Bradley Wogsland, who spent a year at the lab working with BaBar—a detector that records what happens when electrons and positrons collide.

Wogsland started taping comedy sketches as a kid and has posted nearly 400 videos on YouTube. Being a SLACer alternates shots of his family, the lab, and cultural references, including scenes from Lord of the Rings. He’s posted films of the SLAC library, deer lounging in the parking lot, and a col-league talking about a string of bicycle mishaps, titled Physicists Shouldn’t Ride Bikes.

Earlier this year he spent a shift operating BaBar and turned the camera on himself.

“I thought a lot of people would be interested to see how the control room works,” says Wogsland. “As a kid, I had no idea what went on inside a control room to take the data, and I wanted to know.”

The video pans around the room, showing various control screens and the data they contain: luminosity, instrumen-tal flux return, the alarm han-dler. A voice comes over the

intercom and says, “Attention: Automatic end run sequences activated.”

The video has garnered more than a thousand hits and a mixed bag of comments.

“Nice, we need more videos like this,” says one viewer.

“What the heck is a BaBar? In words I can understand,” says another. “R u making electricity?”

A third chimes in, “It really is like Star Trek in there.”

After launching a farewell video—a seven-second shot of his SLAC hard hat, with the theme song from The Good, the Bad and the Ugly playing in the background—Wogsland returned to Tennessee. But he has not hung up his camera.

“I’m creating lab demos for a physics class that I’m teaching this fall,” he says, “and posting them on YouTube so students can see equipment in use before they have to use it in the lab. The potential of this emerg-ing medium is enormous.”

The control room video can be viewed at http://youtube.com/watch?v=dj7gCZTEoq0. Ken Kingery

Editor’s note: We are collecting online videos related to particle physics to share with our readers. Please let us know your favorites at [email protected].

Pho

to: J

ohn

Wei

ssko

pf, S

LAC

7

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

A night of wonderMen and women wearing gaudy dresses, looking for customers under garish neon signs—this is a common sight in Kabuki-cho, Shinjuku, a famous enter-tainment and red-light district in Tokyo, Japan. Walking down an alley past bars and night-clubs, you will see a hand-writ-ten sign posted on a shabby building: “The Accelerator’s Night 3.”

This sleepless town is home to the “Accelerator’s Night,” a science seminar produced by Kenichi Kojima, who organizes group tours to such places as laboratories, factories, and his-toric places. His program is called “Shakai-ka Kengaku ni Ikou!” (Translation: Let’s go on a field trip!). More than 7000 people have registered online, creating a unique field-trip club for adults only.

What’s a science seminar doing in the red-light district? It started with a traffic jam.

For two years, Kojima has been organizing field trips to KEK, the international particle physics center in Tsukuba. On one of those excursions the bus got stuck in traffic. One of the tour guides, Satoru Yamashita of the International

Center for Elementary Particle Physics at the University of Tokyo, killed time by talking about accelerator science, par-ticle physics, and the International Linear Collider project for two full hours. “People on the bus enjoyed his talk very much, so I proposed that Dr. Yamashita have a semi-nar with his colleagues,” Kojima says. He arranged to hold the the first “Accelerator’s Night” at a Kabuki-cho night-club owned by a friend.

Yamashita says he was skep-tical that the seminar would find an audience, but “surprisingly, the place was packed. They are not only interested in the sci-ence but also fascinated by the machine itself. That really opened my eyes.” Novelist Aya Kaida was one of the seminar moderators. “The accelerators are such beautiful machines. I don’t think scientists are aware of that very much,” she says. “It is a shame to not show these beauties to more and more people.”

For one recent seminar the basement nightclub was crowded with about 70 attend-ees, some with physics back-grounds but most with no con-nection to the field. There were

many women in the room—un-usual for a physics talk in Japan. Three experts, including Yamashita, spoke about radiation physics, particle physics basics, and how an accelerator works. “People gathering here are very active in so many ways. It is very important for us to intro-duce our efforts to people like them,” says Junpei Fujimoto, a KEK scientist and seminar speaker. “A new project like the ILC especially needs more attention and understanding from the general public. Hope-fully, we can have seminars like this regularly in different cities.”

Yamashita thinks the semi-nars also give scientists valu-able practice in talking with the public. “We are learning so much from the audiences, such as where their interests lie and how we should attempt to gain more understanding,” he says.

Following a brisk question-and-answer session, the seminar finally ended more than an hour late, and the scientists set off running toward Shinjuku sta-tion to catch the last train home. Rika Takahashi, ILC Global Design Effort

Letters can be submitted via [email protected]

Imag

e co

urte

sy o

f Rik

a Ta

kaha

shi,

ILC

GD

E

RESULTS! The particles of our readers’ imaginations We asked you to use Roz Chast’s cover of the May issue of symmetry as inspiration to go beyond the elementary particles already discovered or theorized and tell us about the particles of your dreams. The dozens of responses were clever, funny, and insightful.

It was difficult to choose a few entries to highlight. Those that stood out most made us laugh or think, and sometimes both.

1st place The Lost File of Elementary ParticlesChuck Yoneda from Stanford Linear Accelerator Center entered The Lost File of Elementary Particles, which mixed scientific principles with humor, winning him first place and an autographed copy of Roz Chast’s cover for the May 2007 issue of symmetry. Runners-up received posters of the Chast cover. Chuck Yoneda, SLAC

signal to background

88

2nd placeLeaptonA particle created anytime someone jumps on the bandwagon in support of an elegant but unprovable theory. Julie Phillips (text) and Greg Kuebler (illustration), JILA, Boulder, Colorado

3rd place BloginoParticles created by non-abelian Blog-Blog inter-actions. Bloginos typically are produced in a very excited state and with a high degree of spin. Even though all their properties have not yet been determined, it is commonly agreed that they exhibit considerable truthiness. They also have the annoying ability to propagate into extra dimen-sions, away from the blogosphere, and generate lots of phone calls.Jacobo Konigsberg, Fermilab

Runners upRockonResponsible for such things as face-melting guitar solos, heart-pumping rhythms, screaming vocals, and hair bands. Observation of the rockon over the airwaves has been on the decline since 1995.Ike Hall, Fermilab

OreoWhen near a small child, the Oreo undergoes spontaneous fission, revealing a creamy center. Note: The center always ends up on one side, illustrating the principle of symmetry violation.John T. Collier, Winfield, Illinois

VelcronHolds together all the seemingly huge particles formed in high-energy collisions at the Tevatron. Since the lifetimes of these particles are so short, it must be the velcron that holds the pieces together until they run into a stronger force, at which time they detach. Comes in two species, the loop velcron and the hook velcron.Paul C. Czarapata, Fermilab

PostitonCarrier of the ultraweak force, the postiton was invented for those jobs for which the gluon is just too sticky. It comes in stacks, just like D-branes in string theory.Lance Dixon, SLAC

9

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

9

10

A new report gives top priority to developing the International Linear Collider, while laying out a plan for science that could be done along the way.

Fermilab’s path to the future

by Elizabeth Clements

Pho

to: F

red

Ullr

ich,

Fer

mila

b

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

11

F ermi National Accelerator Laboratory in Batavia, Illinois is home to the Tevatron, the highest-energy particle accelerator in the world. But in 2008, the

Large Hadron Collider, a proton-proton accelerator with seven times as much energy, will turn on in Geneva, Switzerland and become the center of particle physics research for years to come. By the end of this decade, the Tevatron will shut down, although its world-leading neutrino program will continue. This leaves the lab with a challenge: how will it maintain its central role as a place where particle accelerators produce groundbreaking discoveries in physics?

Any answer must be compatible with the goals of the global particle physics community, which has determined that the next big project should be the International Linear Collider, a 31-kilometer-long accelerator that will smash together electrons and their antimatter opposites, positrons. An international team of scientists has laid out a technically driven timeline in which construction would start in 2012 and take seven years. However, the multi-billion-dollar project will require international management and funding, and getting things organized could take some time.

In February 2007, Raymond Orbach, Under Secretary for Science for the US Department of Energy, raised the possibility that the ILC might take longer to build than the physics community had hoped. Speaking at a meeting of the High Energy Physics Advisory Panel, he asked the US particle physics community to “re-engage” in a dis-cussion of the future of particle physics. If the ILC does not turn on until the middle or end of the 2020s, Orbach asked, “What are the right investment choices to ensure the vitality and continuity of the field during the next two to three decades, and to maximize the potential for major discovery during that period?”

In response to Orbach’s request, Fermilab Director Pier Oddone appointed a steering group to propose a plan for the future of the lab. The plan, Oddone said, should support research and development for the earliest pos-sible start of the ILC, while at the same time proposing options in case it’s delayed. He also asked the group to recommend steps toward even higher-energy colliders than the ILC, in case results from Europe’s Large Hadron Collider indicate a need for those higher energies.

The steering group, led by deputy lab director Young-Kee Kim and composed of particle physicists and accelerator scientists from across the nation, convened in late March. Kim held meetings and town-hall sessions at laborato-ries and experiments from coast to coast, asked for input from the particle physics community, and opened the group’s meetings to anyone who had an interest. Responses included 17 expressions of interest and several letters. The group found strong community support for the idea that a US laboratory should maintain a strong accelerator-based program of particle physics.

After just four months of intense discussions, focused study and vigorous debate, the steering group concurred on a plan.

12

Priorities confirmedThe plan reiterates that the LHC and the ILC are Fermilab’s top priorities. That’s where the physics of the Terascale—a term that describes particle collisions with energies mea-sured in trillions of electronvolts—will be discovered. So Fermilab should continue to participate in the LHC and play a leading role in the effort to make the ILC a reality as soon as possible. In fact, the lab’s goal is to host the ILC, and it has already been meeting with local residents to discuss the possibility of building the collider there.

If the ILC is delayed by a couple of years, the group recommends that Fermilab develop a more intense proton source for its current neutrino program, using the existing accelerator complex. This project would be called Super NuMI, or SNuMI.

Should the ILC timeline stretch even more, the group calls for building a new facility, called Project X for the time being. Project X would combine a new linear acceler-ator with the lab’s existing accelerators to generate high-intensity beams of protons for experiments that address fundamental questions:

Are there undiscovered principles of nature? New symmetries, new physical laws?

Do all the forces become one?

How did the universe come to be?

What are neutrinos telling us?

What happened to the antimatter?

If the global community decides to build the ILC outside the US, the group proposes that Fermilab pursue SNuMI or, alternatively, Project X, if resources and timing permit.

The group stops short of suggesting that Fermilab seek formal approval of Project X. But it recommends starting the initial research and development now, in a way that will also expedite development of the ILC and the industrial base needed to build it. Oddone estimates that this R&D will cost about $50 million, take a few years, and require the equivalent of 30 to 40 full-time employees spread across various labs and universities. With this level of effort, an engineering design could be ready by the end of the decade, at which point the physics community would know enough about progress on the ILC to decide whether or not to proceed with an interim plan.

Project XThe proposed Project X is a linear accelerator 700 meters long—roughly the length of seven football fields—that would be constructed in the center of the Tevatron ring. With 8 billion electron volts (GeV) of energy, it would generate an intense beam of protons that feed into an existing accelerator ring and then into the lab’s Main Injector.

The core technology for Project X is almost identical to that for the ILC; in fact, it would operate as a sort of mini-ILC, one-hundredth the length of the real thing. Both would use cryomodules—vessels that contain niobium cavities, cooled to near-absolute zero—to accelerate particles, although Project X would accelerate protons and the ILC electrons. Project X would require about 36 cryomodules;

the ILC calls for about 2000. Steering group members say Project X could help test the design for the ILC and estab-lish an industrial base in the US for building its components.

The report concludes that the engineering required to build Project X would advance research and development for the ILC. Project X could also accelerate electrons, if necessary, for specific ILC-related studies, says Fermilab accelerator physicist David McGinnis.

Project X would train highly skilled technicians and engineers needed to build the ILC. Maury Tigner, an ILC physicist at Cornell University who served on the steer-ing group, says that if Project X trains people and keeps the ILC program going, that’s a good alignment between the two.

In addition to building a new linear accelerator, Project X would require a number of modifications to one of Fermilab’s rings and its Main Injector. Although any cost estimate made without an engineering design is extremely rough, the group expects Project X would cost on the order of $500 million in today’s dollars, about 10 percent of which would be spent over the next two years for research and development.

The intensity frontierBoth the LHC and the proposed ILC will smash particles together at much higher energies than ever achieved before, creating particles that could not have been observed in earlier machines. This approach to finding new physics is known as the energy frontier.

Project X would explore a different arena known as the intensity frontier: Rather than pour more energy into the particles it generates, it would generate more particles, and thus a more intense beam—10 times more intense than those used in today’s neutrino experiments. This would open a pathway to discovery in neutrino science and in an area known as precision physics.

Neutrinos are among the most mysterious particles in the universe. Every second of our lives, trillions of them stream through our bodies; but since they barely interact with other forms of matter, we take no notice. The sun

13

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

Fermilab Steering Group’s proposed planThe Steering Group recommends the following plan for the accelerator-based particle physics program at Fermilab.

• Fermilab’shighestpriorityisdiscoveringthephysicsoftheTerascalebyparticipatingintheLHC,beingoneof the leaders in the global ILC effort, and striving to make the ILC at Fermilab a reality.

• FermilabwillcontinueitsneutrinoprogramwithNOνA as a flagship experiment through the middle of the next decade.

• IftheILCremainsnearthetimelineproposedbytheGlobalDesignEffort,Fermilabwillfocusontheabove programs.

• IftheILCdepartsfromtheGDE-proposedtimeline,inadditionFermilabshouldpursueneutrino-scienceandprecision-physics opportunities by upgrading the proton accelerator complex.

• IftheILCstartmustwaitforacoupleofyears,thelaboratoryshouldundertaketheSNuMIproject.

• IftheILCpostponementwouldaccommodateaninterimmajorproject,thelaboratoryshouldundertakeProject X for its science capability and ILC alignment.

• IftheILCisconstructedoffshore,inadditionFermilabshouldpursueneutrino-scienceandprecision-physicsopportunities by upgrading current proton facilities while supporting the ILC as the highest priority.

• ThelaboratoryshouldundertakeSNuMIataminimum.

• Alternatively,thelaboratoryshouldundertakeProjectXifresourcesareavailableandILCtimingpermits.

• Inallscenarios,

• R&DsupportforProjectXshouldbestartednow,withemphasison

• expeditingR&DandindustrializationofILCcavitiesandcryomodules,

• overalldesignofProjectX.

• R&Dforfutureacceleratoroptionsconcentratingonaneutrinofactoryandamuoncollidershouldbeincreased.

• ThelaboratoryshouldsupportdetectorR&Dandtest-beameffortsforeffectiveuseoffuturefacilities.

Recommendations taken from Fermilab Steering Group Report, 2007

Pho

to: F

red

Ullr

ich,

Fer

mila

b

14

Project X would connect an ILC-like linear accelerator to Fermilab’s existing Main Injector and Recycler rings to produce high-intensity proton beams.

Project X schematic

Photo: Cindy Arnold, Fermilab

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

15

is a rich source of neutrinos, and the source of another puzzle: Although only one type of neutrino emerges from the sun, it can morph into two other types during its jour-ney to Earth. The neutrino is also at the heart of a theory called “leptogenesis”—the idea that all visible matter comes from neutrinos. If this theory is correct, the report says, “we owe our existence to neutrinos from the big bang.”

Project X could shed light on leptogenesis and illuminate the ordering, or hierarchy, of the three neutrino types, with their three slightly different masses. This information is key to understanding the role of the neutrino in unifi-cation—the idea that all the forces and particles might, at some fundamental level, merge into one.

Fermilab’s accelerators already generate a beam of neutrinos that travel 735 kilometers underground to a detector in Minnesota’s Soudan Mine. In the future, the lab might also provide neutrinos to detectors in the pro-posed Deep Underground Science and Engineering Laboratory, located in South Dakota’s Homestake Mine.

Another project under way at Fermilab, called NOνA, calls for upgrading the existing accelerator and building two new neutrino detectors—one on site and the other 810 kilometers away, at Ash River near the Canadian border. This experiment would look for evidence that muon neutri-nos are changing into electron neutrinos, says John Cooper, the Fermilab project manager. It’s under review at the Department of Energy, and could start operating in 2011.

Project X would greatly increase the intensity of the beams available for these experiments.

It would also provide particle beams for a new generation of precision experiments. These are experiments that try to detect the nearly invisible footprints of very-high-energy phenomena by observing their effects on processes at lower energies.

The discovery that one kind of neutrino can convert into another—known as “flavor violation”—has led physicists to ask whether this also occurs in the charged leptons, the electron, muon and tau. Several theoretical models predict that such conversions should happen.

Project X could produce large numbers of muons for experiments that look for muon-to-electron conversions with 10,000 times more sensitivity than before. Combined with results from neutrino experiments and from the LHC, these experiments might provide support for lepto-genesis or unification.

Project X could also generate beams of kaons that are incredibly pure and intense, allowing experiments that look for rare decays of these particles. These decays offer

a unique way to probe why matter came to predominate over antimatter in the universe.

Sally Dawson, a physicist at Brookhaven National Laboratory, served on the EPP2010 National Academy panel whose 2005 report recommended priorities for US particle physics; she was also a member of the Fermilab steering group. She says she believes the phys-ics goals of Project X fit into the panel’s priorities, and could potentially complement the discovery possibilities of the LHC and ILC.

University of Chicago physicist Mel Shochet, who chairs the High Energy Physics Advisory Panel to the Department of Energy and the National Science Foundation, also participated in meetings of the steering group. He says results from the LHC may be available by 2010, the point at which a decision to build Project X would be made. Depending on the results from the LHC, he says, Project X could become a high priority for the scientific community.

Another steering group member, Tom Himel, an ILC leader at the Stanford Linear Accelerator Center, says he hopes the ILC will be built as soon as possible, making Project X unnecessary. However, he says it would be irresponsible for Fermilab not to propose an interim plan in case of a delay.

What’s nextBefore its formal presentation to funding agencies, the report will make its way through the US particle physics advisory system—Fermilab’s Physics Advisory Committee, the Particle Physics Project Prioritization Panel, and HEPAP.

Kim says Fermilab’s Accelerator Advisory Committee gave the steering group’s plan strong support. While the committee appreciated the broad scope of the plan, it endorsed Fermilab’s effort to make clear that ILC, not Project X, is the lab’s top priority.

Fermilab Director Pier Oddone says he remains deter-mined to build the ILC as soon as possible. He says he’s confident the proposed plan provides the flexibility that Fermilab needs to remain a leader in the world particle physics community, no matter how events unfold, and his next objective is to secure funding for Project X research and development.

If the US particle physics community endorses Fermilab’s proposed plan and the Department of Energy funds it, R&D on Project X could start in late 2008, keeping Fermilab on the pathway to discovery.

Fermilab Deputy Director Young-Kee Kim, far left, chaired the Steering Group charged to propose a plan for Fermilab’s future in the event of a delayed ILC. Open meetings like the one held at Fermilab on June 12 involved many particle physicists.

Photo: Reidar Hahn, Fermilab

16

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

17

The end of The

heRA eRACelebration, anticipation, and a little wistful reflection: The final shift of the heRA accelerator brings more than 1000 people to hamburg for a last hurrah.

By david harris

18

June 30, 2007, 8:00 p.m.Laughter punctuates the excited conversations, a mix of German and English. Drinks are passed around and children dart among the legs of the hundred or so scientists gathered together for one last time. The sky’s blue is deepening: only 90 minutes until sunset. A photographer tries to wrangle the merrymakers into formation while the light is still good. It is the final group photo of the HERMES collaboration, which is responsible for running one of the experiments on HERA, the Hadron-Electron Ring Accelerator, at the Deutsches Elektronen Synchrotron laboratory in Hamburg, Germany.

Tonight, HERA and its experiments are to shut down after 15 years of collecting data. More than 1000 physicists and engineers have gathered at DESY to say goodbye. Each part of the facility is celebrating and commemorating in its own way, while collecting data until the last possible minute. The HERA beams must be turned off at 11 p.m. to ensure that they can power down before midnight and avoid paying surcharges to the electricity supplier for running into the next calendar month.

HERA has already produced a remarkable suite of results that changed the way physicists think about the interiors of subatomic particles. HERA provided a detailed view of the proton and showed how the proton is much more than a simplistic collection of three quarks, two “up” and one “down.”

The last shift is a time to reflect on these achievements, to talk about what is still to come from the data, and to enjoy the com-pany of friends and colleagues, some of whom will not see each other again.

Photos: David Harris and DESY

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

8:30 p.m.: heRmeSOnce the photographs are taken, Jim Stewart, the spokesperson for HERMES, reminisces about his 13 years on the experiment.

“It’ll take a while to realize it is over,” Stewart says, obviously moved to see everybody gathered. “Some of these people I haven’t seen in ten years.”

With the end imminent, many collaborators wanted as much time with their machine as possible. Stewart says people would come to the laboratory to work shift after shift in the control room during the last six months of running.

Seven floors underground, in the HERMES control room, Pasquale Di Nezza, Vitaly Shutov, and Wolfgang Lorenzon work the last data-taking shift.

“We’re very proud to be the last ones,” says Di Nezza. “We’ve all been here more than ten years.”

In that time, the scientists have seen a lot happen, Shutov recalls: “A smart professor broke three interlocks and stopped the whole accelerator. Three times in a row in one shift!”

With the end of the last shift less than two hours away, Shutov says that he will miss “friends, first of all and most of all.” For him, as for others who have worked a long time on the experiment, it’s more than just a job: “You are working, fighting, running, and finally you realize it is an essential part of your life.”

Back above ground, Stewart is enjoying the party, but notes, “It’s a very weird feeling. Yesterday I was sad as the ending festival was going on. Today I’m getting used to the idea that the way I work will change.” He will stay at DESY to conduct more data analysis, dismantle the detector, and tend his on-site paprika crop, another sign of attachment to the lab and the experiment.

Another experiment at the accelerator, HERA-B, closed down in 2003, but many of its collaborators have come back for this event. HERA-B was designed to look for a phenomenon called CP violation. In essence, it asked whether B mesons—particles that include a bottom quark—were the same as their antiparticles, apart from their opposite charge.

HERA-B raced hard to try to beat two other experiments, BaBar at the Stanford Linear Accelerator Center and Belle at KEK in Japan, that were built as “B factories” to produce large numbers of B mesons. In the end, the B factories beat HERA-B to the dis-covery that CP violation does occur for these particles. However, the development work done at HERA-B helped create new types of detectors, including one that’s at the heart of an experiment at the Large Hadron Collider at CERN, the European particle physics lab near Geneva, Switzerland. In addition, HERA-B helped more than 100 students complete PhDs.

Once the B factories began producing B mesons in large quantities, HERA-B turned to examining other particles, including charm quarks, and produced many competitive results, some of which are still being published. Michael Medinnis from the HERA-B collaboration joked earlier that their experiment was “the only HERA experiment not to discover the pentaquark,” a five-quark particle that seemed to have been spotted in various experiments around the world until later evidence effectively ruled it out.

When HERA-B switched off on March 3, 2003, Bernhard Schmidt made the final entry in the logbook: “…in fact, at 6:45 the darkness was quite complete. And nobody around to say good-bye…Sleep well, old lady :-).”

19

The oRiginS of heRAThe concept of the HERA accelerator was born more than a decade before it took its first data.

Around 1977, both CERN and DESY proposed electron-proton colliders to the European Committee on Future Accelerators. ECFA suggested that the two proposals be weighed against each other, and against international plans, before proceeding. A com-mittee led by Chris Llewellyn-Smith and Bjørn Wiik recommended that CERN build an electron-positron collider. Following that, ECFA suggested DESY build an electron-proton collider. The formal proposal was developed in 1981.

HERA used a novel financing arrangement for the time, asking that one-third of the required 600 million Deutschmarks in fund-ing come from outside Germany. This initially met with skepticism. However, after some negotiations, the Italian national laboratory INFN committed 100 million Deutschmarks. Volker Soergel, formerly the director-general of DESY, said this was “a very forceful and shocking statement to the others. It made the plan to raise 200 million DM not so unrealistic.”

Ferdinand Willeke, responsible for overseeing the HERA accelerators, said, “This was very successful, and has been called the HERA model ever since.”

The project proceeded under Wiik’s leadership until the first collisions between protons and electrons were produced on October 19, 1991. HERA would later also run in a mode that collided protons with positrons.

As with all accelerator projects, there were teething problems. This was DESY’s first experience with superconducting magnets, one of which failed during strenuous testing. Willeke commented that the incident was very useful in understanding magnet quenches, in which a magnet heats rapidly, and was, he joked, “an experiment our friends at CERN recently repeated with large success,” referring to a similar problem that occurred during magnet testing for the Large Hadron Collider earlier this year.

However, once the accelerator and detectors were operating, results came immediately. The ZEUS experiment saw five events of a type called “deep inelastic scattering” on the very first day of running, May 31, 1992, and published their first paper on proton structure by September that year.

9:45 p.m.: h1In contrast with HERMES, the last shift of the H1 experiment is quiet. The H1 end-of-run party is scheduled for a few days time. The parking lot is nearly empty and the setting sun seems symbolic.

Four floors underground, the control room still has more than its complement of workers. Two people are assigned to the final shift, Mira Krämer and Tobias Zimmermann, but another four young postdocs hang around “for the fun of it,” as DESY’s Thomas Kluge says. “We were promised champagne, as well.”

“I feel happy and also relaxed,” he says. “I like the atmosphere right now. It’s nice to gather together and store the last moments of beam.”

H1 and ZEUS are the two large, general-purpose experiments at the accelerator. As Franz Eisele of DESY tells the story, about 25 names were suggested for the experiment, but none of them had majority support. Somebody in a cafeteria discussion sug-gested calling the experiments H1 and H2. The H1 collaboration

20

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber 0

7sy

mm

etry

| vo

lum

e 04

| is

sue

07 |

sept

embe

r 07

accepted that arrangement, but the other collaboration didn’t like H2 and wound up calling itself ZEUS. Although the H1 collabo-ration reconsidered their name, nothing ended up replacing the cafeteria suggestion.

The H1 detector was optimized for observing any previously unseen particles that might be produced, including the top quark, which remained undiscovered until Fermilab’s Tevatron found it at a higher energy than HERA could reach. H1 made much prog-ress in understanding the structure of the proton; produced and studied particles containing bottom and charm quarks; helped test QCD, the theory of the strong force; and collected detailed measurements of particle reactions involving the electroweak force.

Throughout its running time, H1 saw spectacular events con-taining possible new particles during the production of W bosons, but their meaning could not, in the end, be clarified and remains an enticing mystery. Eisele says, “These events were our biggest hope, and also our biggest disappointment.”

10:15 p.m.: ZeuSTo get to ZEUS, you drive into the parking lot of a racecourse and event center, park in the back and walk through the security gate to the distinctive above-ground hall that tops each of the HERA experiments. ZEUS physicists could watch events at the racetrack from the rooftop, just as HERMES physicists could watch football matches at the nearby stadium, at least until it was given a roof.

But tonight, nobody cares about anything beyond the ZEUS grounds. The final-shift party is in full swing, and getting to the control room means wading through a congregation of excited, happy revelers. Down in the control room, Roberto Carlin is alone. His shiftmate, Paulo Bellin, has wandered off to check out the party, and Carlin is kept company by colleagues around the world who are hooked in by webcam. Physicists from Fermilab, Geneva, and London are watching from afar, being part of the last shift in their own way.

Carlin is very happy. He says he is on shift by chance; the person who was supposed to be there didn’t show up in Hamburg. “There was a flood to sign up—I was the first to volunteer,” he says proudly.

In the early days of ZEUS, the room was much more crowded. “The beginning was really tough,” Carlin says. Physicists had to spend so much time waiting for the beam to stabilize—often through the night—that they brought in a bed so they could catch some sleep. “We started with four on shift, and the control room was so crowded it was hard to find a place to stand,” he says. “Now it’s quiet and easy to run. But it was time to switch it off—it’s an old lady.”

10:30 p.m.: Upstairs, panic sets in. It seems that the red wine has run out and the partiers are not pleased. But Tobias Haas, incoming spokesperson for ZEUS, springs into action and finds the secret stash. He is dashing about keeping things running, helping set up the projection screen and loudspeakers for the slide show and later karaoke, pouring drinks, and ensuring every-body is having a good time.

Haas’ role might seem a little strange: he is coming in as spokesperson even though the experiment has stopped collecting data. However, he is not concerned. “We will be quite busy for the next five years. My job will be to make sure all this data is ana-lyzed. This is not so easy, as LHC is starting up and that is a strong attraction, especially for young people. However, I’m optimistic: we have data, while others are just promising data.”

21

22

HERA results have shown their value in many ways. One is particularly important at this point in the development of particle physics. The LHC will observe a wealth of particles and collisions, and disentangling them will take a deep understanding of simpler and lower-energy processes. HERA data has allowed the predic-tion of many particle production rates and interaction strengths for processes that will occur in the LHC. This will help physicists interpret data, and also helps show them where to look in the first place. As in all long-running particle physics experiments, the leg-acy of HERA will further reveal itself over years to come.

10:45 p.m.: heRA mAin ConTRol RoomAs people start arriving at the main control room for the 11 p.m. shutdown, an announcement spreads that the final beam dump will happen at 11:30 p.m. The physicists are keen to squeeze every last piece of data out of the machine, and realize they can stop later than scheduled and still have time to power down safely.

Mark Lomperski from the University of Washington is the head of shift in the control room. As the room fills, he says, “This is where one sees it really was a family that built this machine.”

When Ferdinand Willeke enters and moves through the room, he is treated like a celebrity. On August 20, 1988, he had pushed the button to start up the accelerator. Now, nearly 19 years later, he will push it once more to stop the beams for the last time.

11 p.m. passes and a young Russian scientist, Yevgeny Negodin, takes over as shift leader. He is “really impressed” to unexpectedly take that role for the last few minutes.

As the crowd mills about, they tell old stories, catching up with old friends. One physicist pulls out the early logbooks, and a few of his colleagues dig to find their first-ever logbook entries, from back when logbooks were still kept on paper.

11:05 p.m.: The number of people in the control room passes 100, according to a shout from the back of the room.

The process of building an accelerator is long and complex, requiring much patience. Willeke reflects on his 25-year career in particle physics and the challenges along the way. “You just have to take a deep breath and say, ‘This is one step done,’ and the details begin and you do a lot of work over a large amount of time,” Willeke says. With HERA closing down, he says he hopes “the sacrifice will not be for nothing. I hope this will free some resources to go into the ILC,” or International Linear Collider.

Willeke is already dreaming of building the ILC, but that is far in the future. In the meantime, he is leaving one week after HERA closes to work on an accelerator at Brookhaven National Laboratory, Long Island, New York.

11:15 p.m.: A 15-minute countdown is announced. Willeke pulls out more old logbooks and chats with Albrecht Wagner, director-general of DESY. People ready their cameras.

11:20 p.m.: The room is suddenly quieter.11:25 p.m.: “We lost the positrons!” Shouts erupt around the room,

followed by groans, and then laughter. Willeke jokes, “Something suspicious is happening in the south [part of the machine]. I hope somebody from ZEUS didn’t fall into the beam!” Fortunately the proton beam is still running.

Michael Bieler, the technical coordinator for the shift, is on the phone asking the experiments to shut down their high-voltage power supplies, and trying to diagnose the reason for the lost beam.

A countdown begins.

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07sy

mm

etry

| vo

lum

e 04

| is

sue

07 |

sept

embe

r 07

23

heRA AT A glAnCeLocationDeutsches Elektronen-Synchrotron, Hamburg

Data collection1992–2007

ExperimentsH1, HERA-B, HERMES, ZEUS

Tunnels6.3 kilometer circumference ring, 25 meters below the suburbs of Hamburg

Collision modesProtons against electrons or protons against positrons

Construction partners45 institutes and 320 companies from around the world

ExperimentersMore than 1200 from 25 nations

EnergyProtons, 920 GeV; electrons/positrons, 27.5 GeV

Cost€700 million

11:29:44 p.m.: Willeke pushes the button and applause breaks out. Wagner shakes hands with Willeke, offering his “greatest thanks.”

11:30:36 p.m.: The first champagne cork pops in the control room. One sentimental physicist goes to the terminal and sneaks a message onto the electronic notification system: “Thank you HERA. R.I.P.”

July 1, 12:05 A.m.: The ZeuS pARTyBack at ZEUS, the party continues and collaboration members take elevators down into the cavern for a last photograph with their detector.

Elisabetta Gallo, the spokesperson for ZEUS, points out the national groups saying one last goodbye to the sections of the detector they created. The Italian contingent has trouble cramming everybody into the muon system electronics room.

The accelerator tunnel opens and people go to explore. During the evening they will say their goodbyes, with the keenest among them partying and dancing until dawn before heading into down-town Hamburg.

But for now, Gallo looks wistfully across the cavern and says, “It’s very sad, but a bit happy.”

ThE arT of ThE UnsEEn

They’d look right at home in a movie theater: A retro, hand-painted Godzilla stomps through blazing rubble amid swarms of airplanes. A woman throws her head back and screams as malevolent birds watch from a gnarled tree. A boxy cartoon robot casts an ominous shadow.

For all their B-movie flair, these posters go beyond mere entertainment. They advertise talks on serious scientific topics at the Stanford Linear Accelerator Center in California. Godzilla represents political attacks on science; the screaming woman, the dangers of avian flu; and the robot, the long reach of advancing technologies.

“It’s a lot of fun,” says Terry Anderson, head graphic designer with SLAC’s InfoMedia Solutions group, whose posters have become a cherished part of lab culture. “I get to play Hollywood for a little while.”

Posters are a tradition in particle physics, a way of announcing confer-ences, workshops, and other events that bring the community together. Over the past 25 years they have evolved from pen-and-ink drawings, laboriously produced and printed, to eye-popping computer graphics that can be turned out in a matter of hours. Once available only through the mail, posters can now be downloaded from the Internet.

by Ken Kingery

As technology evolves, posters are getting easier to produce and pass around. But it still takes skill and imagination to illustrate the abstract ideas of physics.

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber 0

7

Background illustrations by Sandbox Studio

The role of graphic artists at high-energy physics labs has also changed. Two decades ago, they might have spent 90 percent of their time creating charts and figures for scientific papers and conference presentations. Now that scientists can do much of that work themselves with the aid of graphics software, artists are free to pour their energies into other areas, such as interpreting physics for the public.

“People in the world of physics are used to the blurred boundaries that separate what you can actually see and what you can envision in your mind’s eye,” Anderson says. “The result is a large range of possibilities that any artist would love to explore.”

At the same time, artists say they sometimes struggle to find the proper balance between fact and imagination: How can they grab the viewer’s attention while getting the science right? That can be tricky, involving topics that may be hard to comprehend, let alone visualize.

“Lots of topics are very theoretical and raise questions such as, ‘What does a Higgs boson look like?’” says Greg Stewart of SLAC’s InfoMedia Solutions group. “It’s a challenge, but I enjoy the challenge.”

Joanna Griffin, a graphic arts designer at Jefferson Laboratory in Newport News, Virginia, says, “As an artist you want it to be visually appealing. That sometimes comes into conflict with the science, but you try to strike a good balance.”

Back in the dayIn the early days of particle physics, simple posters in two or three colors required a pen, ink, complicated stencils known as Leroy templates, and plenty of time.

“I had posters that sometimes I worked on for one or two weeks,” says Anna Gelbart, who recently retired after 26 years as a graphic arts designer at triumf, the Canadian national laboratory in Vancouver, BC. “Everything had to be drawn from scratch.” (See her “Rare Decay Symposium” poster, facing page.)

Once created, the poster was sent to a professional printer. One common form of reproduction, lithography, required a series of steps: First, light-sensitive chemicals were applied to a metal plate and a negative image of

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber 0

7

the poster placed on top. Then the plate was exposed to light; wherever the light penetrated, the chemicals disappeared, leaving an image of the poster behind. When ink was applied to the plate it stuck until pressed onto paper during actual printing. Color posters required a separate plate for each color, although they could be applied in rapid succession.

Today, a skilled designer can create a poster in a matter of hours with the aid of programs such as Photoshop and Illustrator. Small quantities may be printed on-site, while larger orders can be placed digitally and delivered by off-site printers in just two days. “The process is a difference of night and day between the old school and new school,” says Anderson. “Mass production used to be an art. Now it’s just production.”

The ability to produce posters in a matter of hours has also raised expectations, and led to ever-quicker turnaround times. “Five years ago people would like posters finished in two weeks. Then it became one week, and today it’s within the hour,” says Fred Ullrich, manager of Visual Media Services at Fermi National Accelerator Laboratory in Batavia, Illinois. “I’m not saying people are demanding; it’s just the way the technology works. Everything is instant, right now, and the time factor is an issue that we’re really struggling with.”

To keep up with the demand, some departments have hired designers specifically trained in the new graphic design techniques. Both JLab’s Griffin and SLAC’s Stewart were hired within the past two years. “I’ve always loved science, and this is a great marriage of what I like to do for fun and my love of physics,” says Stewart. “I never had a clue art work like this was going on at particle physics institutions, but it makes perfect sense.”

Engaging the publicSome of Terry Anderson’s most engaging posters advertise colloquia and lectures for lab employees and the public. Deadlines are often tight;

he may be approached with a title on a Wednesday for a poster that’s due on Friday. This actually gives him a certain amount of freedom. With no time for committee meetings or discussions about what should appear on the poster, Anderson relies solely on his own imagination and skills.

“Most posters have to be so visually accurate that you never get the free-dom to play,” says Anderson. “But the colloquium series allows for that sort of freedom. And most scientists enjoy the art; it makes them feel like stars. Some first-timers can’t wait to see what we create for them.”

To illustrate a public lecture entitled “The Violent Universe,” for instance, Anderson began with a serene picture of the night sky. A red fist bashes through it, tearing a gash that bursts into flame. “The idea was to symbolize violent forces with the fist,” says Anderson, “and to have the fist viciously breaking through the stereotypical peaceful image of the universe.”

Lawrence Krauss, a physics professor and author from Case Western Reserve University, recalls the Godzilla poster that announced his “Science Under Attack!” colloquium at SLAC. “The only input I had in the poster was hearing the general idea and asking if I would mind if it was sort of science fiction-like,” Krauss says. “The final piece was a surprise, and I loved it.” He adds that even when a poster does not quite nail the physics concepts, “if it’s not blatant, and it gets people to the lecture, they will hear what I have to say.”

Looking aheadToday, the Internet is triggering a new round of poster evolution. Now that every conference and event has its own Web site, there’s no longer a need to list the names of the organizers or other details on the poster, and this allows more creative freedom.

“We use the website to convey as much information as possible, which allows us to keep our e-mail announcements and posters fairly uncluttered,” says University of Texas postdoctoral fellow Kurtis Williams. “Hopefully, this makes them less likely to be deleted, discarded, and forgotten.”

Although more posters are being displayed online, and a growing number are available for download, most conference organizers still distribute hard copies to every major institution where potential attendees might see them, on the theory that people are much more likely to hang onto a poster if it is delivered to them.

Meanwhile, graphic designers are exploring new ways to reach audiences—for instance, by creating movies and animations that show physics phenom-ena, from free-electron lasers and particle colliders to elementary particles, in new and exciting ways. These short films may be what’s needed to catch the attention of a culture accustomed to high-tech special effects.

“Advertising has become much flashier, and tool sets used in movies and television are now readily available for anyone,” says Stewart, who is

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber 0

7

working on a long animation of SLAC’s Linac Coherent Light Source, which is now under construction. It allows the viewer to fly over the completed building and shows how a free-electron laser beam is created.

“Beyond the attractive quality of being able to capture the imagination and attention of the audience, movies and animations can show information to the audience,” says University of California, Berkeley Professor Bernard Sadoulet, who presented a SLAC colloquium on the Cryogenic Dark Matter Search. “We try to show very visually what the laws of physics are telling us, and it often works quite well.”

Although these new technologies show promise, don’t expect them to replace posters at particle physics labs any time soon. “People still like seeing posters sitting up in real space and not on a computer screen,” says Anderson. “The artistic side of posters activates a different part of the brain. They’re like a dessert—or like a scientific appetizer.”

day in the life: HERAfest

on June 29, 2007, when Albrecht Wagner told an assembly of nearly 1800 people to go to lunch and return at 2 p.m. for a surprise,

nobody could have expected what was coming. Wagner, director-general of the Deutsches Elektronen-Synchrotron in Hamburg, was master of

ceremonies at HERAfest, which marked the closing of the Hadron-Electron Ring Accelerator after 15 years of operation. For two days, participants heard talks highlighting the history and achievements of HERA and its four experiments, HERA-B, HERMES, H1, and ZEUS. While those talks were entertaining and often amusing, they paled in comparison to Wagner’s surprise.

At 2 p.m. exactly, the crowd, which had been enjoying German delicacies and beer, turned to see a truck carrying a pantheon of Greek gods and goddesses, Hera herself played by a 6-foot drag queen in high heels, with servants and attendants in waiting. Other actors played Zeus and Hermes; lacking a tie to Greek mythology, the H1 experiment was represented by a bottle of Heinz-brand sauce.

After parading through the DESY site, the procession mounted the stage at the front of the enormous tent set up for the event. There the DESY staff performed a show—part cabaret, part pantomime—that had the audience laughing uproariously, even those who didn’t speak fluent German.

As day turned to evening, the festivities continued. The tent was transformed into a human table-football arena, and Greek-god-themed cocktails were served to those dancing among gold-painted human statues until well after midnight.Text: David HarrisPhotos: David Harris, Barbara Warmbein and Christian Motzek

30

31

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber 0

7

31

with the Painting

With an ancient art, an engineer captures the intricate swirls of nature.

gallery: amy lee segami

FLOW

To artist and engineer Amy Lee Segami, water is no ordi-nary substance—it is her canvas. Using her knowledge of fluid mechanics, Segami paints on water in a contempo-rary version of the ancient Asian art form of Suminagashi.

“Ever since I was a kid, I was very much drawn to the creativity and expression in drawing and painting,” Segami says. But her father insisted that she train in a technical field, so she got a bachelor’s degree in mechanical engi-neering and a master’s degree in mechanical aerospace engineering from the Illinois Institute of Technology.

After graduating, Segami worked for five years in engi-neering development for pharmaceutical companies. But in 1989, she started to re-evaluate her life and felt there was something missing. To balance her life and return to her Chinese heritage, Segami started taking art and culture classes. One of her classes was a Chinese brush painting class, which is where she learned of Suminagashi.

Suminagashi originated in Asia more than 2000 years ago and was practiced by Japanese Shinto priests in the 12th century. Suminagashi artists would drip black ink in water and let it flow freely before transferring the image onto paper. Segami was immediately drawn to Suminagashi because of its resemblance to experiments in fluid mechanics, in which she could add smoke to air or dye to water to show how the air and water were moving. She says Suminagashi is a natural fit because it com-bines the two things she loves—science and art.

Her contemporary version of the ancient art form uses many bright colors and creates a more deliberate artistic expression by incorporating properties of fluid mechanics. Segami drips acrylic paint on the surface of water and then uses a variety of tools, such as traditional Chinese brushes, feathers, acupuncture needles, and sticks, to create turbulent and laminar flow patterns that give her

32

AboveMomentum38 × 12 inches, 1990 Acrylic on rice paper

RightProbability of Certainty20 × 32 inches, 1996Acrylic on museum board

RightMaxwell Mist32 × 40 inches, 1991Acrylic on museum board

33

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

art a three-dimensional quality. Adding color to the patterns shows how the water is moving and “makes the invisible visible,” Segami says. Once she is happy with the painting, she carefully lays a piece of rice paper on top of the water to capture the image. “The color is moving, and the water is moving, so you have to catch it really fast,” she says.

Segami usually does not know in advance exactly what she wants to paint—only that she wants to express a certain dynamic of flow. The idea comes into the painting as she is creating it. She says her paintings are not rigid representations of reality, but are suggestions. The intricate flow patterns Segami sees in nature are inspiration for her artwork. “The beautiful swirls, the movement—the flows have such a complex design,” she says. “I want to share the insight, the feeling, and the pleasure that science can be beautiful.”

Segami says her paintings are a balance of probability and certainty. While she is certain about the properties of fluid mechanics and how the water will react, she is never really sure how well the colors will illustrate the flow patterns.

Although she spends most of her time working on her paintings, Segami is still involved in engineering and is currently working with BASIC International Inc., helping to market a technology that produces energy from waste.

Art and science are similar in many aspects, Segami says. They both involve creativity, innovation, and discov-ery. She hopes her paintings will help people realize that art and science fit together. “People often think of art and science as two completely different things, but they truly balance each other,” Segami says. “While art and science can each do their own task, together they can do amazing things, especially when it comes to creativity and innovation.”

Segami’s artwork will be on display at the Fermi National Accelerator Laboratory art gallery through November 1. The art gallery is open to the public before and after events in the “Arts, Lectures, and Film” series.

Text by Amelia WilliamsonPaintings by Amy Lee Segami

gallery: amy lee segami

34

AboveRing Leader32 × 40 inches, 1992Acrylic on museum board

AboveTesla Coil 32 × 40 inches, 1994Acrylic on museum board

BelowPassion16 × 40 inches, 1991Acrylic on museum board

35

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

Computers, disco, and double-knit The late 1970s were a special time for me. The radio played disco, George Lucas released the first of the Star Wars movies and Alice Waters, at her Berkeley restaurant, Chez Panisse, was shaping a cuisine featuring fresh, local ingredients. I lived in Los Gatos with my husband and three young daughters. Just out of technical school, I was hired by Digital Equipment Corporation (DEC) as a computer field-service technician. What a trip! I couldn’t believe my good fortune; I would have access to companies and organizations that the ordinary citizen on the street did not have.

I discovered I was the only female in a group of 34 service technicians, confirming my suspicion that affirmative action played a role in getting the job. I did not mind; I was starting a career that would be much more interesting than working on an assembly line. The DEC technicians dressed in suits and ties; I followed their example by acquiring a wardrobe of double-knit pantsuits and blouses with floppy bows. I was sent to work at places like the US Geological Survey, Sunset magazine, Lockheed Missiles & Space, Ridge Vineyards, Stanford University and Hospital, and The Nielsen Company.

Our maintenance contract with Stanford Linear Accelerator Center required us to respond within two hours of a service call, 24/7, when the beam was on. After assisting with several service calls, I finally got to perform preventive mainte-nance on the PDP-8e systems in the lower tunnel. Although the computers were the size of large microwave ovens, sometimes they were stacked with their peripherals in bays more than five feet tall, forcing us to crawl inside or stoop to make repairs. I would take off my jacket and neckwear for these jobs, and even had my hair bobbed so it would fall back into place after being

upside down. The PDP-8e was a 12-bit computer with 32KB of memory—less than 1/100,000th the storage space of the smallest iPod nano now available—and operated with eight basic instruc-tions. Today it seems unreal that such limited computing power could have guided a beam of electrons. As I recall, most of the other DEC computers at SLAC were from the larger, 16-bit PDP-11 family.

Once in the tunnel, I was warned to be careful when using the restrooms. The architects never envisioned women working down there, so there were no separate facilities, and the closet-sized bathrooms had no locks on their doors. My outfit also seemed out of place; it was so hot that many of the scientists and technicians wore loose khaki shorts and sandals.

Having finished the preventive maintenance in the lower tunnel, I got to go upstairs for a glimpse of the klystron gallery. It was a jaw-drop-ping experience. I had never seen a klystron, a device that generates microwaves used to acceler-ate particles in the beam below. Here were hun-dreds of them, in a line nearly two miles long. I was in awe of the work the entire complex performed.

One day, as acting supervisor, I reminded a technician that he needed to complete preven-tive maintenance on a particular PDP-11. He returned about three hours later. Scott was a big, charming man, a veteran of stage and stand-up comedy. He rolled his eyes, shrugged his shoulders and put on a pathetic face. “I went right to where the computer was. It wasn’t there,” he said. “The **%#! building wasn’t even there! I drove around a couple of hours trying to locate the correct hut. Do you think SLAC will com-plain about not complying with our contract if we can’t find the system?” This produced a hearty round of laughter; SLAC was notorious for moving computers around. I suggested that he call the information center, get the group’s new phone number and ask for directions. Of course my advice worked, and there were no repercus-sions from getting the job done a day late.

Looking back, my seven years with DEC were a highlight of my work life. Those fond memo-ries include the actual work I did at SLAC and the experiences and stories of other technicians who performed vital jobs there. Today, I am older, tire easily, and have grown too large to crawl inside a computer system and fix it. Just as well; today’s computers are too small for that.

Barbara Manning lives in Fremont, California, and works part-time as a human resource consultant.

Barbara Manning wears a work outfit in this family portrait from about 1980. Her oldest daughter, Robin Decker, left, is a consultant with Johnson Controls working at Fermi National Accelerator Laboratory in Batavia, Ill.

36

sym

met

ry |

volu

me

04 |

issu

e 07

| se

ptem

ber

07

essay: barbara manningP

hoto

cou

rtesy

of B

arba

ra M

anni

ng

ep timing ok

separated with trans. bump (0.5 mm vertical separation)

on october 19, 1991, at 6:50 p.m., Bjørn Wiik logged the first collisions in the new electron-proton particle collider at the Deutsches Elektronen-Synchrotron in

Hamburg. The legend among DESY accelerator physicists is that the “father” of the Hadron Electron Ring Accelerator (HERA) jokingly called the rate at which the first collisions occurred “the lowest luminosity ever recorded.”

HERA was the first and only accelerator to collide two different types of particles: electrons and 2000-times-heavier protons. By steering electrons traveling close to the speed of light into a beam of oncoming protons, scientists were able to search for new subatomic forces and map the proton’s interior with unprecedented precision.

Making electrons and protons collide at high rates was a huge challenge. Two completely different and independent accelerator rings were necessary to accelerate the particles. Ferdinand Willeke was responsible for commissioning the proton ring in 1991. When protons had been accelerated and stored at high energy for the first time, the electron team quickly injected the electrons. “Then it all went really fast, or at least that’s what it seemed like to us,” says Willeke. “When the luminosity experts from one of the experiments told us that they had a signal we were all thrilled. It wasn’t half as hard as we had expected.”

HERA operators filled 55 collision logbooks before they switched to electronic logs in 2001. On June 30, 2007, the HERA accelerator produced its last collisions.Barbara Warmbein, DESY

Document courtesy of DESY

Evening shift, October 19

Proton beam ~ 72 μA ≅ 1010

Electron beam ~ 2 × 109

Translation

Brought electrons and pro-tons into the right transversal position with the ± 7 m position monitors. Adjusted timing so that the two bunches meet in WWP-Nord [the North Hall, home of the H1 experiment]⇒e gamma coincidence rate rises by a factor of 2!

⇒first e-p collisions in HERAOct. 19, 1991 at 6:50 p.m.

logbook: first HERA collisions

A theory, in everyday language, differs little from a guess or a hunch. But in science

we reserve the word for a well-developed idea based on experimental evidence.

Scientific theories summarize and codify what we know about a subject. In physics they take the form of a set of mathematical equations. These describe phenomena that have already been observed and predict the out-comes of new experiments.

A theory can be well tested in one area, and still leave open questions in areas where it has not yet been tested.

In particle physics we call our well-established theory “the Standard Model.” Particle physicists try to add new features to this theory that don’t contradict anything that has already been tested, but at the same time predict the outcomes of future tests. We call this “model building.” It is guided by mathematical ideas and by our questions about features of the existing theory that seem to beg for further explanation. This process provides “straw-man” options for experiments to probe. As experimental data confirm or refute those options, theories are extended and made more precise.Helen Quinn, Stanford Linear Accelerator Center

SymmetryA joint Fermilab/SLAC publicationPO Box 500MS 206Batavia Illinois 60510USA

Office of ScienceU.S. Department of Energy

symmetry

explain it in 60 seconds