New particle detector used to study another pathway to carbon creation in stars – The Source

Washington University in St. Louis is part of a collaboration that has provided new insight into one of the universe’s primordial reactions that made all life on Earth possible.

The Texas Active Target (TexAT) particle detector is the centerpiece of a collaborative experiment to test whether other particles — specifically stray neutrons — might be involved in carbon creation. (Image courtesy of Texas A&M)

Carbon, known universally as the building block of life, is generally believed by scientists to have formed inside the cores of stars. Now scientists are using an experimental device to test whether the element could have been produced under additional circumstances.

A research collaboration involving physicists from Texas A&M University, the University of Washington and Ohio University uses a particle accelerator known as TexAT in combination with powerful neutron beam lines at the John E. Edwards Accelerator Laboratory in Ohio to see if carbon can be produced more efficiently if a sufficient neutron flux is also present in carbon-producing regions in stars.

Lee Sobotka, professor of chemistry and physics, both in Arts & Sciences, first proposed the idea of ​​using a time projection chamber to determine the influence of neutrons on the triple-alpha process in 2017.

“This experiment married a very special tool – an active-target time-projection chamber – with a low-energy accelerator capable of producing near-mono-energetic neutrons,” said Sobotka, also a fellow at the McDonnell Center for the Space Sciences at the university. “It is a one-of-a-kind union that has provided the answer to a question first posed 55 years ago about making the seed for heavy element synthesis.”

Charity (left) and Sobotka

The team concluded in a recent study published in Nature Communications that the role neutrons play in carbon creation is much smaller than previously thought. Sobotka and Robert Charity, a research professor of chemistry in the arts and sciences, are co-authors of the new study, along with physics graduate student Nicolas Dronchi and Viktoria Ohstrom (a 2021 University of Washington alumnus), now a graduate student at the Massachusetts Institute of Technology.

The experiment is a flagship product of the Center of Excellence for Nuclear Training and Academic Research (CENTAUR), a $10 million, multi-institutional effort led by Texas A&M and funded by the U.S. Department of Energy/Administration national nuclear security. WashU has been part of CENTAUR since 2018.

Sobotka will give a talk about these findings at 4 p.m. Thursday, May 5 in the Louderman Building, Room 458. Learn more about Texas A&M University research.

Irene B. Bowles