Undergrads enlighten with Dark Matter research
By Katy Brown
College of Liberal Arts and Sciences
It’s a tremendous opportunity when undergraduate students are able to contribute their research skills to an internationally recognized experiment. Physics professor Martin E. Huber has been offering physics and electrical engineering students experience in his lab designing and testing Superconducting Quantum Interference Devices (SQUIDs) since 1991. These SQUIDs play a key role in an experiment called the Cryogenic Dark Matter Search II (CDMS-II), a collaborative effort among several institutions and universities across the United States. The CDMS-II researchers are attempting to detect Weakly Interacting Massive Particles (WIMPs), a type of “dark matter.”
“Dark matter is a term used to denote several types of hypothetical particles whose electromagnetic radiation is so low that they have yet to be detected by any means, but whose existence is indicated by their effect on visible matter,” Huber explained. “Should this experiment be successful, it could prove the existence of WIMPs and thus validate much of recent cosmological theory.”
Huber’s lab plays the important role of developing and evaluating series arrays of SQUIDs, the only devices sensitive enough to act as a preamplifier in the WIMP detectors. Huber is particularly proud of the level at which the interns participate in the collaborative experiment. “Each of the 12,000 SQUID chips that comprise the one hundred and 20 SQUID arrays in the primary scientific experiment has been characterized by one of my undergraduate interns. These are not test devices; these are the actual science devices,” Huber said.
Huber will be traveling to the experiment site, located deep in a northern Minnesota mine, at the end of February. He will work with other collaborators to move the experiment, including the large quantity of SQUIDs into full operation by the end of March. The experiment has already proven successful as early research results, published in Physical Review Letters and Physical Review D, have set world-record upper limits on the possible flux of dark matter candidates.
Each semester, eight to 10 students work in Huber’s lab. Diversity of backgrounds and views is important for Huber, as it gives the students a broader perspective of the personal interactions in science. First generation, nontraditional, and foreign students all contribute to the lab. “Despite national under-representation of women and some minorities in physics and engineering, such students have always held a prominent place in my lab, often far outnumbering national averages,” he said. Every year an average of two interns are involved in the UCDHSC Undergraduate Research Opportunities Program. Although a large percentage of students are from physics and electrical engineering, students from other departments, including mechanical engineering, mathematics, computer science and even arts and media, have found the lab a welcoming place to pursue their goals.
Students can begin their research experience testing the CDMS-II chips, but they soon take on additional projects tailored to their experience and interests. The internships are flexible: some interns are paid, others are volunteers, and yet others earn class credit through independent study or senior design projects.
One of Huber’s priorities is for the students to have a realistic experience working in a lab. He keeps activities structured by holding weekly lab meetings that are run efficiently and professionally. “I want to give the students not only the technical experience of working in a lab, but also planning skills that are crucial to research. This is something that is not formally taught,” Huber said. Because the projects are ongoing and the lab staff changes sometimes every semester, Huber requires that excellent recordkeeping be a priority. Wall-to-wall, the lab’s shelves are stocked with well-organized record books -- an indication that the students take him seriously.
“What helps in the learning experience for these students is that I have a hands-off management style and high expectations,” Huber explained. “I disagree with the standard procedure of using undergraduate researchers only in positions requiring little responsibility or skill. My students excel because they are challenged to perform at their peak.”
Regardless of his hands-off approach, the students are getting hands-on experience that employers and graduate schools favor. Sulistiyo Indah, a December 2005 graduate, still volunteers in the lab while looking for a full-time job. In her most recent interview, the prospective employer impressed upon her that her lab work as an undergraduate student would be invaluable in starting her career, as companies do not always see that kind of real-world experience in their candidates. “I’m very excited about finding a job now,” said Indah. “This lab experience has been really beneficial for me.”
A new phase of the CDMS-II collaboration is just beginning. Proposals are in the works for even larger detectors that may not only find dark matter, but measure its attributes as well. Whether through this collaboration or other experiments, Huber expects there will be opportunities for many other undergraduates in the years to come.
Photos: At top, left to right: Triet Nguyen, Duan Phan, and Sulistiyo Indah review the closed-loop response of the integrator circuit on a high-frequency spectrum analyzer. Center photo: Bruce Hines, an undergraduate physics student who works in the lab on a UROP grant and who will graduate in May, prepares a SQUID for testing. Bottom photo: Ken Anderson, another UROP student, tests the integrator circuit board that processes the signal from a SQUID. Story edited by Martin Huber.