While science as a profession has made strides toward gender equality, some fields lag—notably physics and engineering. For female scientists, cracking the glass ceiling in these fields requires not just dogged passion and dedication but also a refusal to be cowed by long odds.

A prime example is Lia Merminga, a rare woman in the top echelons of physics. Today, she heads the accelerator division for TRIUMF, Canada’s national laboratory for particle and nuclear physics, but she learned much of her determination and perseverance—not to mention her technical knowledge and teamwork skills—at the Fermi National Accelerator Laboratory’s (Fermilab's) Tevatron accelerator when she was a grad student.

"The motto of our experiment was, 'often wrong, never in doubt,' " Merminga says. The team printed t-shirts with that motto, written in Greek, acknowledging the fact that many of the theories they tested were eventually proved wrong. "But for at least a period of time, we were never in doubt that they were correct."

Likewise, Merminga never doubted that she could excel in science. After earning her Ph.D. from the University of Michigan, Ann Arbor, in 1989, she joined the accelerator theory group as a visiting physicist at Stanford’s SLAC National Accelerator Laboratory in Menlo Park, California. Three years later, she joined the Center for Advanced Studies of Accelerators (CASA) at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. She worked her way up through the ranks and in 2002 became director of CASA's beam physics group. In 2008, TRIUMF recruited her to lead its accelerator program, making her one of the most senior scientists in Canada.

Today, Merminga manages her dream project: leading the design and construction of a new accelerator facility to produce rare isotopes for nuclear physics and medicine. "It has been a huge opportunity for me to expand as a scientific leader," she says.

When she comes home after work, her priorities change from nuclear physics to nuclear family. She's married to a fellow physicist, and they have a teenage son.

Science Careers sat down with Merminga at the February 2012 meeting of the American Association for the Advancement of Science (which publishes Science Careers) in Vancouver, Canada, to discuss her rise in physics, navigating the competing demands of being a scientist and being a mother, and the direction she hopes to take accelerator physics research.

These interview highlights were edited for brevity and clarity.

Q: How did you first become interested in physics?

L.M.: A friend of mine gave me the biography of Madame [Marie] Curie as a birthday present when I was 13. I was fascinated. Then, a physics teacher that I had in high school, who was superb, largely influenced me. She demanded excellence from us, and she gave excellence to her teaching. A woman who is so professional and who has such high standards—this was very inspiring to me.

Q: What attracted you to accelerator physics?

L.M.: Initially, I didn’t have any preconceived plans. I entered the physics department at the University of Athens. In my third year of undergraduate studies, I realized it wasn’t enough. I wanted to keep going.

My current husband became a postdoc at Fermilab and made me aware that they had a graduate program in accelerator science. I was fascinated by the fact that you are studying something that is quite deep. These are really very rigorous scientific questions but you have the opportunity to make progress in relatively short time scales compared to high-energy physics.

Q: Why do these questions fascinate you?

L.M.: I feel I am contributing something to the advancement of knowledge and to the improvement of quality of life—for example, by working on accelerators that produce medical isotopes.

Accelerator science touches upon many fields, and I find that very attractive. I can design and build accelerators that are used to study the most fundamental questions of our nature, to study the Higgs particle or dark matter and dark energy. And here at TRIUMF, I work on nuclear physics accelerators and the cyclotron, which is used for materials science and nuclear medicine. So, you can enable science on multiple fronts.

Q: What do you consider your major accomplishments to be so far at TRIUMF?

L.M.: To get people that used to work in separate divisions to work together and learn from each other. The division I am responsible for used to be split, and there are some historical differences and tensions between the two groups. I had to bridge those gaps and unite them. We’re making big progress.

Also, one of our challenges at TRIUMF is that our plans and our goals are typically more ambitious than our resources can support. But so far, we are quite successful in keeping our science program strong while building our new accelerator.

Q: What are your hopes for the accelerator division at TRIUMF?

L.M.: Ultimately I want TRIUMF’s accelerator division to be one of the top-ranking accelerator divisions around the world. There are certain prerequisites in order to accomplish that goal. Mainly, routine things need to be streamlined so they don’t require extra resources and effort or time, so we can focus on frontier research and breakthroughs.

Q: What was it like moving from a postdoc at SLAC to becoming a staff scientist, then director of the Center for the Advanced Studies of Accelerators at Jefferson Lab?

L.M.: I’ve been very lucky in my career. At Jefferson Lab, we were looking for somebody to be in charge of CASA, and the efforts we made to attract an outside person didn’t lead anywhere. Finally the division director, Swapan Chattopadhyay, asked me if I would consider taking the job. Now, I had no managerial experience before. So he was sticking his neck out big time doing that. He was the first one to recognize me as a scientific leader and give me the opportunity to grow in that direction.

Q: There are very few women at the highest levels of administration in physics and accelerator physics. What has your experience been like?

L.M.: My field is male-dominated; there is no question about that. I feel that men tend to be almost too assertive. There were times that I walked away from a meeting and cried because I perceived that somebody did not treat me respectfully. Not recently, but when I was younger and less established.

I feel it is very important to be good technically. And then nothing else matters. If you know your stuff, then you are okay. That’s my experience.

Q: Have you noticed a difference in how people treat you due to your gender?

L.M.: I’ve always had this feeling that people looked at you and tried to associate you with a familiar female figure in their life—either their mother, daughter, or wife. And that those associations don’t allow for straightforward interactions that focus on the technical aspects of the subject we’re dealing with.

Q: As you’ve moved up in the professional ranks, has that treatment changed?

L.M.: Certainly things are a lot better now than they used to be when I was 35. I’m also more mature as a scientist and as a manager. Probably it is no surprise that people listen to me more carefully and respect my guidance now.

Q: What is it like raising your son and building a career?

L.M.: There are many days in the week that I think I don’t do a very good job either as a mother or as a scientist. When I am away, I worry about how he is doing, has he done his homework, and does he miss me. On the other hand, I would not have it any other way. I believe that seeing his parents pursuing what they really love might be one of the best lessons he could get from us. I’m hoping this will stay with him and guide his own choices.

Q: Why do you think women are underrepresented in physics in particular?

L.M.: I used to go to my son’s classes in elementary and middle school and give lectures. At that stage, boys and girls are equally as excited in scientific subjects. I think between middle and high school, we lose a large fraction of the girls.

One factor is that boys tend to be more aggressive in the classroom, and they are not as afraid to ask questions. I went to an all-girls high school where I didn’t experience this sort of competition. I think this gave me the assurance and self esteem to say, “I’m also good, and I can pursue physics and math.”

Q: How would you describe the challenges facing young women in graduate school now?

L.M.: Overall, things aren’t equal, exactly. I think it is getting better because I think men are accepting women in the workforce and in graduate schools. But I would not be surprised if young women are facing similar problems every once in a while.

On average, I don’t feel I’ve been discriminated against. If I’m invited to give a talk somewhere and I’m chosen because they want to have gender equality—by and large, I want to take this opportunity. And I try to do a very good job. But I will use the opportunity to be out there and say, "Yes, women can be as good as men, and better. We are also a significant force in this field."

Q: Do you have advice for young women who are interested in a physics career?

L.M.: When I was young, I heard a woman who gave a talk, and I think she was at a very high level at the National Institutes of Health at the time. She said she had two pieces of advice to young women starting up in scientific and engineering fields. One of them is, “Stay focused.” And the other is, “Don’t take no for an answer.”

I found both of them to be crucial to my success—especially “don’t take no for an answer.” This may not have to do with my being a woman, but if you come up with an idea somehow the tendency is that people want to turn down the idea. They say either, “We tried it and it didn’t lead anywhere,” or, “It’s not going to work.” Don’t stop. Don’t. Just keep pushing. Not all ideas are good, but don’t stop at the first "no." To be determined and to persevere is very important.