APRIL 3, 2019
During an introductory nuclear physics course her sophomore year, Elizabeth Mae Scott developed a need to understand things from their most basic, original structure. The course showed her how math becomes a language that physicists use to describe the world around them.
“Fundamental physics is a way to pry at the cosmos. It’s really fun to try to understand the tenets of how things work, to push the boundaries of how we describe our universe,” she said.
Scott earned bachelor’s degrees in physics and mathematics from Tulane University. Now a graduate student in nuclear physics at UT, she continues to push those boundaries as part of a collaborative experiment called Nab at the Spallation Neutron Source at Oak Ridge National Laboratory.
When a neutron decays, it decays into three particles: a proton, an electron, and an antineutrino. The relationship, or correlation, between the electron and the antineutrino is known as the parameter a, or “little a.” Scott and her collaborators at the Nab experiment aim to measure that parameter with a precision of 10-3, which would make their measurement the most precise ever.
The experiment will either confirm the the physics theory that explains how the building blocks of our universe interact—known as the standard model—or it will reveal where the model breaks down, which will let scientists start to refine it. Either outcome has implications for physicists, who use a in numerous equations and experiments. A change in the standard model would mean a change in our fundamental understanding of the universe.
To collect data, Scott uses a custom seven-meter-long magnetic tube to guide decay products from the neutron source to the experiment’s detectors for measurement. The magnet is specifically designed to guide the decay products along its magnetic field in much the same way that a river current carries objects downstream, but with far more precision. To minimize variation, Scott maps the magnetic field by setting a probe inside the magnet and using a laser tracker to track its position, making micro adjustments as needed. Seven meters above the lab floor, with her hands on the threaded rods holding the probe, she carefully maneuvers the probe inside the magnetic tube and takes precise measurements.
“We have to understand everything that can affect our measurement, said Scott. “The more accurate our map of the magnetic field is, the more that helps us. So while there are steadier areas of the magnet where our measurements are anywhere from 5 to 20 centimeters apart, in the crucial areas we’re measuring millimeter by millimeter,” Scott said.
While she gathers data for her thesis Scott has begun searching for postdoctoral positions, hoping to stay in the field of neutron physics. She enjoys the science as well as the community of scientists and colleagues. Ultimately, she wants to return to where she first found her inspiration: the classroom.
“Mentoring has been rejuvenating for me, which is why I want to teach. I want to help others find what I found exciting about physics. When I see that initial spark of interest in someone, I’m going to feed that fire.”
Scott also hopes to get more women into STEM fields, regardless of whether they pursue physics.
“I’m from West Virginia, and growing up as a girl in a rural community, it was not expected for me to like science. But getting more women into science is beneficial for all involved,” she said.
“Rural communities like [those in] Appalachia can benefit from having more of their young people in science, the physics community can benefit from having scientists with different diverse backgrounds, and young women can feel empowered by getting involved with physics and math. It empowered me. I personally know how it can make you feel confident in the world, and I want to give more people that.”
Original Source: CATALYST newsletter from the University of Tennessee, Office of Research and Engagemet
CONTACT: Raphael Rosalin (865-974-2152, firstname.lastname@example.org)