College of Science News
Trio of physics students honored for their work on IceCube neutrino project
A team of physics students from The University of Texas at Arlington have received an award for their contributions to the IceCube Collaboration, a particle experiment based at an observatory at the South Pole.
The team was honored with the IceCube Impact Award, which is given annually to junior researchers to recognize efforts dedicated toward improving IceCube’s particle detector performance. This year’s recipients are Grant Parker, a fourth-year doctoral student; Ben Smithers, a third-year Ph.D. student; and Ibrahim Safa, a former UTA undergraduate and now a Ph.D. student at the University of Wisconsin. Ben Jones, UTA assistant professor of physics and Neutrino Oscillations Physics Coordinator for IceCube, is faculty mentor for Parker and Smithers and was Safa’s mentor while he was at UTA.
Important contributions to the award-winning project were also made by Blake Watson, formerly a graduate student in Jones’ lab, and four colleagues in Germany.
The IceCube Neutrino Observatory, constructed at the Amundsen-Scott South Pole Station in Antarctica, is designed to search for neutrinos, which are subatomic particles having almost no mass. The project aims to address several big questions in physics, such as the nature of dark matter and properties of the neutrino. IceCube, which encompasses one cubic kilometer of ice, is a new kind of telescope, able to see high-energy neutrinos that can only come from deep space. It also observes cosmic rays that interact with the Earth’s atmosphere, which have revealed structures that are not presently understood.
“I am so proud of what our IceCube team at UTA has accomplished,” Jones said. “The Impact Award is a well-earned recognition of their hard work over the last few years, which has improved the precision of the experiment for studying experimental signatures of new physics in high energy neutrino oscillations. Congratulations to Grant, Ben, and Ibrahim for this well-deserved award, and for continuing to build UTA’s reputation as a neutrino physics research powerhouse on the world stage.”
The Impact Award was given to the UTA team for the analysis of data using software called SnowStorm, which was created by Jones, Safa, and Watson. SnowStorm was designed as a way of efficiently treating uncertainties when an analysis contains many parameters. It has primarily been used to treat the large number of uncertainties involved with the ice below the South Pole and is now being applied to other analyses in IceCube. Parker and Smithers joined the project to further develop the software and to be among the first in the collaboration to use it in new analyses.
“SnowStorm was developed to model the optical properties of the deep South Pole glacial ice,” Jones said. “Understanding these optical effects has been a longstanding challenge for IceCube, since the way light travels though the ice determines the telescope’s efficiency for detection of neutrinos, but the glacier has a complex optical profile connected with the climate history of the Earth over the last 100,000 years.”
Jones noted that the award-winning advances were motivated in part by realizing the sensitivity needed for the IceCube search for sterile neutrinos, which was co-led by UTA. The results were published in the journal Physical Review Letters in September in an article titled “eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory.” It is the world’s most sensitive search for these elusive new particles, Jones said.
Parker, who received dual bachelor’s degrees in physics and mathematics from Bard College at Simon’s Rock in Great Barrington, Massachusetts, in 2017, focuses on searches for new physics through data collected by IceCube. This involves developing software and performing analyses on massive amounts of data.
“Our team was awarded the first ever Impact Award in the group category, which has made the experience even more surreal,” he said. “To receive the first award of its kind within an experiment of 400 world-class scientists is an unforgettable moment in my life, as it is still easy for me to doubt my abilities and contributions this early in my career, making the experience quite validating on a personal level. It is a humbling experience to work with such innovative and passionate researchers, and I am overjoyed that the collaboration took the time to highlight the tremendous efforts of this team.”
Smithers, who graduated from the University of California at Santa Cruz in 2018 with a B.S. in Physics and a B.A. in Mathematics, helped develop a suite of Python scripts that incorporated the SnowStorm method into simulated IceCube events. These became the basis for a simulation set for a “global fit” to the data and is the work that led to the impact award.
“I feel incredibly proud to receive the Impact Award and I hope to keep doing cool science with the collaboration,” he said. “I think IceCube is important since it’s a big part of attempts to answer the most fundamental questions there are in science. Through IceCube we can better understand the weird and unexplained properties of neutrinos. Through them we might just discover there’s much more to physics than we know today.”
Parker is currently conducting an analysis looking for interactions between neutrinos and matter that is not described by the Standard Model of particle physics. The analysis is on track to set the tightest constraints on a particular interaction parameter in the world, he said. Smithers has recently focused on examining special kinds of events called “cascades,” which have a blob-like topology as viewed in IceCube, and so lack directionality for the most part. Because of this, they have been considered background events and have largely been ignored. Smithers is investigating whether cascades can be used to search for a hypothesized new kind of particle called the sterile neutrino.
“I know I speak on behalf of the Physics Department in saying how proud we are of our Ph.D. students, Ben Smithers and Grant Parker, and our alumnus, Ibrahim Safa,” said Alex Weiss, professor and chair of the Department of Physics. “This is a great honor for our students and for their mentor, Ben Jones. Congratulations to all; you have brought great credit to yourselves and to our department.”
UTA’s IceCube group is supported by funding from the U.S. National Science Foundation. Learn more about the IceCube Neutrino Observatory at https://icecube.wisc.edu/.