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ReActions – November 2014

November 19, 2014 Volume 31
Featured Highlight

A Star on Earth

At the Energy Department’s Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: creating a star on Earth.

The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas — hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars.

Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

Click to watch “A Star on Earth”

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The Center for Nuclear Science and Technology Information offers cool classroom tools and suggested reliable resources to help you make lessons about fission and fusion understandable and fun.

Fusion is the process by which the Sun and other stars generate light and heat. It is a nuclear process where energy is produced by smashing together light atoms. It is the opposite reaction to fission, where heavy isotopes are split apart.

It’s most easily achieved on Earth by combining the isotopes of hydrogen: deuterium and tritium. Hydrogen is the lightest of all the elements, being made up of a single proton and an electron. Deuterium, often called “heavy water,” has an extra neutron in its nucleus. Tritium has two extra neutrons, and is therefore three times as heavy as hydrogen. In a fusion cycle, tritium and deuterium are combined and result in the formation of helium, the next heaviest element in the Periodic Table, and the release of a free neutron.

Deuterium is found one part per 6,000 in ordinary seawater, and is therefore is globally available, eliminating the problem of unequal geographical distribution of fuel resources. This means that there will be fuel for fusion available to all nations, as long as there is water on the planet.


The U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) is a collaborative national center for fusion energy research. The Laboratory advances the coupled fields of fusion energy and plasma physics research and, with collaborators, is developing the scientific understanding and key innovations needed to realize fusion as an energy source for the world. An associated mission is providing the highest quality of scientific education.

The Princeton Plasma Physics Laboratory  is a world-class fusion energy research laboratory dedicated to developing the scientific and technological knowledge base for fusion energy as a safe, economical and environmentally attractive energy source for the world’s long-term energy requirements.

Kelsey Tresemer is an engineer at the Princeton Plasma Physics Laboratory (PPPL) in Princeton, New Jersey. She’s worked on a variety of fusion-related projects, most recently the upgrade to NSTX to improve performance and confinement time. She is acting as a Port Integrator for the ITER project, based out of Cadarache, France, coordinating the union between diagnostics and structure in one of the diagnostic port plugs. She specializes in plasma-facing components and is working towards her Master’s degree in Nuclear Engineering with an emphasis on Nuclear Materials.  In a Q&A with the American Nuclear Society, Kelsey discusses what drives her passion about fusion research.

How long have you been working at PPPL?

I have worked at the laboratory about five years, but I was also an intern at the lab for a summer while in college.

What do you study and why? What questions are you trying to answer with your work?

Fusion is the same reaction which takes place inside the sun, where two hydrogen atoms are slammed together to produce a helium atom and high energy particles. We study that same process here on Earth at PPPL by creating a plasma, or superheated gas, and containing it with large magnetic fields.

My job involves researching how to provide protection and shielding from the plasma and high energy neutrons. Plasma is not very dense, but it is extremely hot, so any material it encounters will lose a few atoms from the surface to the plasma.  A dirty plasma will lose heat and energy faster than a clean one, so it’s something to avoid or be tactical about, such as only introducing favorable materials to the plasma. Additionally, a fusion reaction produces high energy neutrons which tend to travel large distances through normal materials unless there is shielding in place to stop them. I study all these interactions, research what materials are best suited to the different situations, design components with those materials, and supervise their installation. The hope is that once we solve this rather challenging issue of how to contain the plasma and its byproducts, we will be much closer to using fusion for energy production.

How did you become interested in this subject?

I was freshman in high school when I first learned about nuclear fusion. I had thumbed to the back of my physics book and was completely fascinated by the idea that you could release so much energy by simply combining two hydrogen atoms. The concept would mean that our society could create endless energy and not worry about pollution, radioactive waste, carbon emissions, or fuel shortages. Even as a teenager, I knew how dependent our world was on petroleum. I also knew that fuel source would not last forever. Fusion would be a perfect solution to that problem, providing energy for our planet for the next thousand years. This idea captivated my imagination and I remember thinking how amazing it would be to help work on making fusion energy a reality.

How much money do early, mid, and late career scientists in your field typically make?

It depends on your education, particular field, and whether or not you’re working for a government research laboratory or a private company. However, it is not uncommon for engineers right out of college to begin at $55K, hit mid-career at $100K, and finish at $150-175k a year. Private companies will typically pay higher salaries, but you may not be able to have as much input on what type of work you do.

Describe a typical work day for you.

My day starts with a morning meeting in which all the ongoing projects for the day are discussed by their respective job managers. It doesn’t take very long, but it helps to keep everyone organized and informed about the plans for the day. Many of our projects require some heavy construction, which can cause conflicts with other people wanting to move or work in the active space. This meeting helps everyone coordinate the work which needs to be done and keeps people safe.

Next, I check up on the techs who are working on the installation of a project I’ve designed and am managing. I walk out to the worksite and talk with the techs about any issues which have been discovered or to answer questions about the next steps in the installation process. If there is a problem, we discuss possible solutions until we find one that fits and then I return to my office to initiate updates to drawings, procedures, and documents so that the problem won’t be repeated again if the parts are ever remade.

In the afternoons, I usually have at least one more meeting, which can involve anything from a cost and scheduling review in which I give the status of the jobs I am supervising, to a meeting broadcasted from France about neutronics analysis results which might change the design of a particular part or assembly. In the spare moments, I read papers about designs of shielding materials and components, have interesting discussions with my coworkers about which materials to use in different applications, check drawings for accuracy, write specifications and requisitions for the procurement department, and perhaps even devote some time to writing research papers for submission to conferences. No two workdays are ever exactly alike and it’s hard to be bored when you’re an engineer.

What process do you follow to find answers?

One of my favorite things is when I get a knock on my office door and see someone there with a problem for me to solve. When I first started working as an engineer, I would simply dive into the deep-end of a problem without any plan, but after collecting advice from the many veteran engineers around me, I have a bit more technique. 1) When someone comes to me with a problem or even and idea for something that they need me to look at, the first thing I now do is get as much information as I can from the source. I will wring information out of the physicist and then I will go look at the problem, in person. Sometimes I take pictures of the problem, talk to the techs that found the problem, and even go talk to the designers who created the drawings of the part. 2) I sit down with a pad of paper and begin outlining a plan. I start with the information I’ve gathered and begin putting together an initial plan. 3) I am lucky enough to work with some of the brightest and best minds, with decades of accumulated experience, so my final step is to gather them together for a review. At this point, I have a general outline of the problem, a few ideas of how to fix it, but what I need is final approval to make sure the whole scope of the issue is covered. I invite a selection of technical experts to a review from departments all around the lab, and we discuss the plan. They review my ideas, add some of their own, approve my path forward, and then I can start the real work. Research and problem-solving is not done alone; it’s accomplished by a whole group of people, each with their own field of expertise.

What is the role of technology in your job?

These days, if you have an idea for an experiment, it’s actually prudent to build the device first inside a computer system than to physically create it from steel and copper. We use computers every single day, sometimes for simple presentations and office work, but often to run very complicated and technically intricate analysis programs which require that you know a little bit of programming. Computers and being able to write and run analysis programs is rapidly becoming a big part of my job.

How do you think scientific research, which contains a lot of technical language and data, can be more accessible to the general public?

When you work in any scientific field, every day, every week, for years, it’s hard to remember that your neighbor next door might not know what a stellerator or a plasma is, so I believe it’s extremely important that scientists practice communicating their ideas in such a way that anyone can understand them. I also believe that science needs to support the jobs of trained scientific journalists, people who understand that gap between the public and the sciences, and who are willing to act as a bridge between them. Having the interest and support of people is what keeps funding flowing into scientific research, so it is very important to invite the general public to learn about what we do and why we do it.

What do you enjoy most about being a scientist?

I’ve mentioned before how I love it when someone comes to me with a problem to solve, but that really is what I love about working as an engineer. There is something very satisfying about taking a problem or challenge and fixing or improving it. It doesn’t matter if it’s simply figuring out which type of bolt to use or if it’s completely redesigning an intricate system in a plasma experiment, I love the feeling of looking back on the project and knowing I was a part of making it better.

What do you enjoy the least?

Paperwork! Another big part of my job is simply keeping track of all these parts, assemblies, drawings, procedures, and schedules which guide my work. This means I spend a decent part of my day updating and writing. It’s not my favorite thing to do, but it pays to be good at it because it winds up being the framework upon which you hang your design.

At the Energy Department’s Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: creating a star on Earth.

The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas – hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars.

Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.



This activity is intended for use in high school and introductory college courses to supplement the topics on the Teaching Chart, Fusion: Physics of a Fundamental Energy Source, produced by the Contemporary Physics Education Project (CPEP). CPEP is a non-profit organization of teachers, educators, and physicists which develops materials related to the current understanding of the nature of matter and energy, incorporating the major findings of the past three decades. CPEP also sponsors many workshops for teachers.

Energize Your Classroom Isotope Discovery Kit $589.95

Shelve the dry textbooks and one-dimensional charts. Using the Isotope Discovery Kit, you can energize your classroom and make science come alive!

Developed by nuclear engineer and ANS member Bill Wabbersen, the Isotope Discovery Kit, provides 9th–12th grade students with an understanding of isotopes and their relationship to the line of stability through an engaging hands-on group activity that they won’t soon forget.

Anatomy of an Atom Classroom Activity $1.00

The Anatomy of an Atom die cut sheet is a fantastic activity for Boy Scouts and Girl Scout workshops! This activity designed for middle and high school students, makes creating an atom mobile fun and easy.  String not included.

Full color, 2-sided,  11” X 8.5” card stock

Teacher Resource Guide Detecting Radiation in Our Radioacitve World Free Download

The Detecting Radiation in Our Radioactive World resource guide may be reproduced for non-commercial purposes.

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