Inside the underground labyrinth that leads to the Large Hadron Collider (LHC) at CERN, the physics institute that straddles the border of Switzerland and France, Bilge Demirköz, a 28-year-old high-energy physicist from Istanbul, guides a tour to a painted green wall and a matching unmarked door. "We are about to go into the world's largest manmade cavern," she says, her voice echoing through the fluorescent-lit tunnel. It's the end of July, and just hours from now this door will be closed to visitors for good.
Demirköz opens the door and leads the tour onto a narrow gangway that's stationed at one end of ATLAS, the largest of the four detectors built to study particle collisions inside the LHC. The 46-meter-long detector looks like a giant rotary engine, and although it is about the size of a space telescope, it is designed to look at the absolute smallest pieces of the universe. Demirköz gestures toward the bladed shaft in front of her, which stands 25 meters high. "You are now looking at the muon detector--the glorious, the huge muon detector," she says. Later she adds: "I know that some people look at it as playing with big toys. For me it's really spiritual."
Her empirical faith has led Demirköz to search for answers to some of the most daunting questions in the universe. Currently, she does so as a research fellow at CERN. Next week, CERN will take a giant step toward studying some of nature's deepest and most fundamental questions when it sends its first beam of protons around the LHC. The protons will travel 27 kilometers along the ring-shaped underground tunnel. In October or soon after, 14 years after the project's initial approval and 10 years after construction began, a beam will be introduced traveling in the opposite direction, and ATLAS will tell scientists what happens when the protons collide at 7 TeV, a much higher energy than any manmade particle collision in history. Demirköz will be watching from close up.
The pursuit of physics
Demirköz grew up in Istanbul, Turkey, steeped in the region's poetry, especially the modern poet Nazim Hikmet and the ancient Mevlana (Rumi). She was attracted to math at an early age, picking arguments with teachers when she was 6. When she was 14, she traveled to Geneva for a mathematics competition. Afterward, her high school math team toured CERN, and Demirköz decided then and there that this was work she wanted to do.
Demirköz left her native country in 1997 to study math at the Massachusetts Institute of Technology (MIT) in Cambridge. But she quickly switched her focus, declared a major in physics, and pursued math and music as minors. "At the time, I was definitely more successful in mathematics than I was in physics. But after taking a lot of graduate courses in mathematics, I began to think that at some level mathematics is an artifact of our own imagination," she says. She went on to do a master's degree at MIT, also in physics, and last year she obtained her Ph.D. in particle physics from the University of Oxford in the U.K. Now, she says, "I'm in physics because I'm trying to understand something that is bigger than me."
In 2001, she visited CERN again, honoring her earlier promise to herself, and soon her trips to Geneva became routine. At first, she worked on the Alpha Magnetic Spectrometer, a particle physics detector intended for the international space station. She joined the ATLAS group in 2004, incorporating her work on the semiconductor tracker into her Ph.D. thesis. She moved to Geneva in 2005.
Today, Demirköz is one of 1900 CERN scientists working on the ATLAS experiment, which will look for particles that theory predicts but are as yet undiscovered, such as the Higgs boson. "It's an experiment in which we really explore the deepest and darkest questions about nature," she says. She is part of a team of 200 physicists focusing on the detector's trigger mechanism, a multitiered system that decides which events should be recorded. She has a very cool title: Triggermeister. "What connects the detector readout to physics is the selection process of the events, and that's the trigger. For me, it was an obvious choice.”
Starting in October, two bunches of 100 billion protons will whip around the 27-kilometer LHC tunnel, in opposite directions, at nearly the speed of light. Every 25 nanoseconds, the two beams will cross paths, resulting, hopefully, in about 20 proton-proton collisions. The ATLAS detector is like a giant traffic camera that photographs the intersection of the proton beams.
Atlas's Triggermeisters--Demirköz is one of three--establish the selection criteria for the trigger to make sure that the data recorded are the data "that we are really looking for," she says. It's an important job; if the wrong criteria are chosen, the most important events could be missed.
Throughout her training, teachers have told Demirköz that as a woman she would have a hard time in math and physics. "I was told many times in high school, many times in university, and a couple of times as a graduate student. Only after I obtained my Ph.D. did I find the confidence to not bother with such people. I would just walk away," she says.
Courtesy, Bilge Demirköz
Bilge Demirköz in Uskudar, Istanbul, carries the Olympic flame on 6 July 2004, helping it along on its way to Athens. In physics too, she is eager to work on projects that require collaboration to succeed.
Developing that confidence took time, she says, because, being a woman, she was under constant scrutiny. Others assumed that, as a woman, she had been admitted to fill a quota. It was up to her to prove otherwise.
But role models can help with that, and at ATLAS, role models for women are not hard to find. "It means a lot to see a woman taking ATLAS into the data-taking phase," says Demirköz, referring to Fabiola Gianotti, the next spokesperson for ATLAS.
Still, Gianotti hopes to see more women in top spots in science. "More and more women from the new generations are undertaking a career in physics," Gianotti says. "If research in physics is what they really want to do, they should pursue their aspirations and goals with determination and enthusiasm. They should not give up; there is no insurmountable obstacle."
Loss and action
On 30 November, Engin Arik, an experimental high-energy physicist from Turkey's Boazii University, an ATLAS collaborator, and one of Demirköz's mentors, was traveling to Isparta for a workshop on designing the Turkish accelerator with two of her students, Őzgen Berkol Doğan and Engin Abat. Also on the plane were physicists Şenel Boydağ, Iskender Hikmet, and Mustafa Fidan, all from Doğuş University. The plane crashed, killing all 57 people aboard. Demirköz was friends with all of the physicists. "Surely, to cope with the death of six physicists, three of whom were very close to me, hurt me deeply. I was a wreck," she says.
It was not the first time she had lost a mentor. Gian-Carlo Rota, her mathematics and philosophy professor at MIT, died when Demirköz was only 19. She decided, with a friend, to pay homage by helping to write up his lecture notes. "Repeating what he had said and written was a way of keeping the promise not to lose his memory," she says.
She approached Arik's death in the same way, paying homage by taking action. After Arik's death, the ATLAS Women's Network established the Engin Arik Fellowship, which allocates funds to support Turkish students to work at CERN in the Summer Student Program. Demirköz contacted banks and other organizations in an effort to expand the program. This year, the number of fellows grew from one to three, with Turkey's Akbank sponsoring the other two, thanks to Demirköz's efforts. "Professor Engin Arik cared deeply about her students," Demirköz says. "The future was everything to her, and the future lay 'not within her grasp,' she said, 'but in her students' vision.' "
Inspiration, talent, and an empirical worldview
Last winter, Demirköz was in a serious skiing accident. "I nearly died," she says. She lost consciousness for a moment and as she came to, "I was not really awake, and I was not sleeping either, but I could hear voices. I could not open my eyes, and I could not feel my body, but I was in a lot of pain. It must have lasted probably 15 seconds, but to me it felt like a lifetime."
That moment, she says, reminded her why she finds physics special. Mathematics, she says, is a lonely, isolated pursuit, like a dream state, something a person can do without any contact with the outside world. But physics is "not just a construction of your own brain," she says. "With physics, you start using your five senses. You start exploring the world and communicating with other people; communication is the essence of beating that loneliness."
It is also, she says, a key career skill. Demirköz advises women in Turkey who are interested in science to focus on language. "Language is often a barrier in how well you can explain yourself and your work. Especially when you work in a large collaboration like ATLAS or any other LHC project, language is even more important, as your work depends on your communication skills."
Demirköz was one of 567 young physicists accepted to attend this year's prestigious meeting with Nobel laureates, held in June in Lindau, Germany. At the event, these young researchers were reminded to meet and mingle with the laureates, as their next invitation to the meeting would come only after winning their own Nobel. About one-third of the young researchers attending the meeting were women. All of the laureates were men.
"There have only been two women who won the physics Nobel Prize. I surely hope that the number will increase so that we will have more role models for young girls to follow," Demirköz says. Perhaps she will be one of them? "Inspiration combined with young talent can produce great results," she says.