Zhaowen Tang, of Los Alamos National Laboratory’s Dynamic Imaging and Radiography group, received a prestigious Early Career Research Program funding award from the Department of Energy’s Office of Science. The program, now in its 13th year, is designed to bolster the nation’s scientific workforce by providing support to exceptional researchers during crucial early career years, when many scientists do their most formative work.
"Supporting early career scientists is a priority for the Laboratory and is vital to continuing our world-class research," said Director Thom Mason. "I congratulate Zhaowen on this recognition and look forward to seeing the accomplishments he makes throughout his career."
Tang’s project, "Understanding the 10 seconds neutron lifetime discrepancy," was selected for funding by the Office of Nuclear Physics. His research will look at neutron lifetime at the one-second level, which is necessary to improve predictions of the elements generated from the Big Bang.
Neutron lifetime and the Standard Model of particle physics
The Standard Model of particle physics describes how all known elementary particles behave under three of the four known forces of the universe: the electromagnetic, weak and strong interactions. Under this theory, the free neutron decays 100% of the time into a proton, electron and antineutrino, with a lifetime of about 15 minutes.
In combination with other experiments, the neutron lifetime can provide constraints on many extensions of the Standard Model. There are primarily two different methods to measure the neutron lifetime: experiments based on cold neutron beams and experiments using ultracold neutron bottles. The results of these two methods differ by 9.6 seconds, which corresponds to a chance of 1 in 3.5 million that the two results are compatible with each other.
Two possible explanations for this large discrepancy are: unaccounted effects in the interpretation of data (systematic error) in one or both of the methods, or a new mode of decay of the neutron that produces thus far unknown and undetected particles.
Tang’s new project aims to measure the neutron lifetime to the one-second level using an alternative method with completely different systematic errors compared to previous measurements. A result that agrees with the bottle experiments would suggest that there are unaccounted systematic errors in the beam measurements and a result that agrees with the beam experiments can be interpreted as a discovery of a new hidden decay mode of the neutron.
"I am extremely honored at the selection, and I am excited to take this experiment from the R&D phase to execution," said Tang, who joined the Laboratory in 2014. "I feel very fortunate to work at Los Alamos, where scientists are allowed to pursue new ideas and are supported through many internal funding opportunities, which allows us to work on projects ranging from fundamental science to weapons physics."
Tang has a wide portfolio of research interests, including proton radiography, neutron decay and dark matter searches. He has been the principal investigator for multiple Laboratory-funded research projects, Seaborg Institute and science campaign projects. He has authored or co-authored more than 30 papers with over 600 citations and has given numerous invited talks at multiple conferences and workshops.
Tang received his doctorate in physics from Indiana University, and his bachelor’s degree in physics from the University of Texas-Austin.
About the Early Career Research Program
The DOE Office of Science Early Career Research Program provides an annual funding opportunity for researchers in universities and DOE national laboratories. Established in 2010, this program supports the individual research programs of outstanding scientists early in their careers and stimulates research careers in the disciplines supported by the DOE Office of Science.
See all of the 2022 Early Career Research Program Awards (pdf).