Feature: MSU is Poised to Investigate the Origin of the Elements
Boasting the world’s most powerful continuous-wave cyclotron, MSU scientists can now begin to unlock the secrets of the universe.
Have you ever looked up into the sky on a clear night, gazed at the stars, and wondered where it all came from? Most people are at least vaguely aware of the Big Bang, the cataclysmic explosion that brought our Universe into being, about ten to fifteen billion years ago. However, this is not the full story. The Big Bang originally only produced mostly hydrogen gas, some helium, and small traces of lithium and other light elements. But the periodic table that we all studied in freshman chemistry lists over 100 elements. The air that we breathe is composed mainly of nitrogen and oxygen, and the ground that we stand on contains all kinds of elements, most importantly silicon and iron. True, the stars including our Sun are mainly composed of the hydrogen made in the Big Bang. These stars shine because they burn their hydrogen in nuclear fusion reactions. And these stars make up more than 90 percent of all visible matter. But the stuff on Earth and other planets is decidedly different! So the big, fundamental question is: Where did all of this matter come from? What is the origin of the elements?
Years of astronomy research with modern instruments, like MSU’s soon to be completed SOAR telescope in Cerro Pachon, Chile, have produced great progress in answering this question. We now know that these heavy elements are most likely “cooked” in the interior of stars at incredibly high densities and temperatures. An even more interesting source of the heavy elements can be found in the explosion of supernovae, the universe’s most brilliant fireworks that mark the end of a certain class of stars. Understanding these processes is the goal of nuclear astrophysicists, who work at the interface between astronomy and nuclear physics.
All atoms that make up the elements consist of nuclei and their associated electron clouds. The nuclei of the atoms in turn are composed of neutrons and protons. Adding more protons to a nucleus results in an atom of a different element. This type of transmutation of the elements, the ancient alchemists’ dream, can be accomplished under the extreme conditions in the interior of stars or during the explosion of a supernova. It involves complicated sequences of nuclear processes, in which protons and neutrons are captured by nuclei to form even bigger nuclei. These reactions compete with others in which bigger nuclei decay into smaller ones. To understand this complicated interplay of reactions that lead to the creation of the elements, one must know the nuclear physics properties of all nuclei involved. This task is complicated by the very short lifetimes—less than a billionth of a second—of some of the nuclei involved. Somewhat surprisingly, though, these nuclei, their properties, and their reactions can also be studied under terrestrial conditions in modern cutting edge nuclear physics laboratories. And this is where MSU’s National Superconducting Cyclotron Laboratory (NSCL) comes in.
The cyclotron laboratory was founded at MSU in 1959 and became a national-user facility, the NSCL, in 1980. It has produced many results at the leading edge of the worldwide nuclear science effort and helped us gain a thorough understanding of the nuclear structure and the reactions of nuclei. The research conducted here has been widely recognized and led to the current ranking of MSU’s nuclear science group as number two in the entire nation, only slightly behind MIT. Its annual budget of over $15 million is mainly financed by the U.S. National Science Foundation and provides the largest individual federal grant to Michigan State University.
This summer the NSCL is ready to take the next step. After an extensive overhaul and a $20 million upgrade of the facility the NSCL is ready to study the origin of the elements in our Universe.
The NSCL is located on MSU’s south campus, next to the Chemistry Building and across the street from the Michigan State University-Detroit College of Law. About 120 full-time MSU employees, plus 40 graduate and 60 undergraduate students, work here. Among them are leading scientists from around the world that were attracted to MSU by the NSCL’s international reputation as a first rate science facility. Teams of scientists from many countries around the world come here to take part in experiments and make use of the world-leading research opportunities provided at the NSCL, right here on MSU’s campus. At the NSCL, MSU’s graduate and even undergraduate students have the unique opportunity to study fundamental questions side-by-side with some of the world’s leading scientists.
The NSCL’s new rare isotope production facilities allow us to study the kinds of processes that enable stars to produce the elements around us, one atom at a time! The 116 known elements have a total of less than 300 stable isotopes. (Isotopes are nuclei with different numbers of neutrons.) A total of about 6,000 isotopes, however, are postulated to exist. And less than half of them have been discovered so far. The processes that produce the heavy elements proceed along certain paths in the nuclear isotope landscape and necessarily must involve many neutron-rich isotopes not yet discovered. The origins of the elements can thus only be understood if the missing isotopes are found and their properties studied. This is the core mission of the new NSCL facility that has started operation this summer and that was inaugurated on July 27th.
During the next decade, this facility will provide a flood of new data that are sure to advance our basic understanding of the origin of the elements. Understanding the basic question of where all matter comes from is contributing more than just increasing our knowledge in the field of nuclear science. It is a fundamental part of mankind’s aspiration to explore the frontier of the unknown. And as such the quest to find the origin of the elements is an essential part of our culture. The very same question has provided a common thread through the ages dating back to the ancient Greeks who theorized the world to be composed of only four fundamental elements. New knowledge of the origins and of the methods utilized to solve this mystery should be a basic component of every student’s education, even a liberal arts education.
The 20 faculty members who lead the nuclear science effort at MSU are also among our best teachers. They teach basic and advanced physics and chemistry to many thousands of students each year and are uniquely qualified to merge brand-new insights into fundamental questions with more traditional textbook wisdom. It is through this classroom contact that every MSU student can benefit from the interaction with the world-class researchers at the NSCL.
In addition to contributing to basic science and education, the technology developed at the NSCL has led to important spin-offs for medical use. For example, the NSCL has built a compact superconducting cyclotron for use in the cancer radiation therapy at Detroit’s Grace Harper Hospital. The NSCL’s design for a new proton cancer therapy accelerator is the basis for a cancer treatment facility to be located at the PSI laboratory in Switzerland. This is yet another example where basic research of fundamental questions seemingly removed from our daily needs, and simply driven by human curiosity, has contributed to the production of useful devices that improve the quality of our lives.
What does the future hold for the NSCL? The new facility will produce world-class research opportunities for the next decade. But our nuclear and accelerator scientists are already planning ahead for a project further down the road, on an even grander scale.