Made of stars: The origin of heavy elements from neutron star mergers or massive stars
|Date||5 February 2020|
The detection of gravitational waves and electromagnetic light from the binary neutron star merger, GW170817, offers a new window into previously inaccessible questions. In this colloquia, I will focus on one of these; what the origin of the so-called r-process elements that make up half the elements heavier than iron? These include elements of high value (e.g. gold) and even some necessary for advanced life on Earth (e.g. iodine). I will highlight how the physical conditions created in neutron-rich material ejected through these mergers provide the ideal location for the synthesis of these elements, while the energy released in their decay powers an electromagnetic signature that may be straightforward to detect. An open question remains if mergers produce some, most or all of the heavy elements, and I will discuss both mergers and alternative suggestions, along with how future observations may enable us to discern the origin of every element on the periodic table.