Prof. Dr. Stefan Tapprogge
Institut für Physik, ETAP
Institut für Physik
Mittwoch, den 02.05.2018
um 13:00 Uhr s.t. im Lorentz-Raum 05-127, Staudingerweg 7
Kaffee und Tee ab 14:00 Uhr
Talk had to be canceled due to illness!
Kyle Wendt, Lawrence Livermore National Laboratory, US
Title: The quenching puzzle of $beta$-decay $beta$-decay, where a neutron turns into a proton (or vice versa), is the dominant decay mode of atomic nuclei. This decay process offers a unique window to study the fundamental laws of the universe, to probe the origin and synthesis of the elements of matter, and to understand the evolution of stars. For more the 4 decades, $beta$-decay has presented a challenging puzzle for theoretical nuclear physics. Theoretical predictions of $beta$-decay rates of for all but the lightest nuclei are systematically larger than observed rates. This is often attributed to an apparent quenching of the axial-vector coupling constant, $g_a$, in the nuclear medium compared to the decay of the free neutron. The mechanism behind this quenching is a source of controversy and contention, and has thus far eluded first-principles calculation. I will present recent efforts to address this controversy and provide a pathway to solve this decades old puzzle.