Researchers from Argonne National Laboratory have revealed new insights into how stars produce heavy elements, with findings published in Astronomy & Astrophysics on September 27, 2024.
While stars are primarily composed of light elements like hydrogen and helium, they engage in nucleosynthesis deep within their cores, leading to the formation of heavier elements through the fusion of these light nuclei.
The study sheds light on the neutron capture processes that are crucial for the production of various heavy metals in stars. There are three types of neutron capture processes: the s-process (slow), r-process (rapid), and i-process (intermediate). Each plays a role at different stages of a star's lifecycle, with the i-process particularly important for producing specific heavy elements such as lanthanum and barium in growing white dwarfs.
The researchers measured nuclear reactions that influence lanthanum production in the i-process, confirming that rapidly growing white dwarfs are viable sites for this process. The presence of lanthanum, alongside elements like barium and europium, aids scientists in understanding the conditions under which the i-process occurs.
This discovery marks a significant step toward pinpointing the astrophysical locations of stars that exhibit i-process signatures.
Additionally, researchers have identified a new asteroid, 2024 PT5, which will orbit Earth from September 25 to November 25, 2024. Dubbed a 'mini-moon,' this event is expected to recur in 2055.