Notre Dame Chair in Astrophysics Timothy C. Beers collaborated with Anna Frebel, associate professor of physics at the Massachusetts Institute of Technology, on a review article about the formation of the heaviest elements in the universe. The article, about the cosmic origins of the rapid neutron-capture process (the r-process), was published Jan. 2, 2018, in Physics Today.
The article, “The formation of the heaviest elements,” describes how the r-process has built up elements heavier than iron, and that the process is now believed to take place primarily in neutron-star mergers.
The observation of a neutron star merger in August 2017 was named Science magazine’s scientific breakthrough of the year. The concept of the r-process was first suggested in 1957, when astrophysicists theorized that the universe’s heaviest elements are formed through a series of reactions, and later suggested this could possibly occur when two neutron stars collide. Though early research pointed to the possibility that the r-process originates in supernovae, Beers’ and Frebel’s paper describes that the supernova theory should be ruled out, following new observations of one ultrafaint dwarf galaxy.
The two researchers have combined forces with other astrophysicists worldwide to comb through thousands of old stars in their search to find more that are enhanced with r-process elements.