Speaker
Stephanie Lyons
(National Superconducting Cyclotron Laboratory)
Description
The r process is known to produce roughly half of the abundance of the isotopes of heavy elements. Models of the r-process depend upon theoretical calculations of various nuclear properties such as those from QRPA and Hauser-Feshbach. Sensitivity studies have shown that the final abundance distributions of r-process nuclei are greatly impacted by uncertainties in nuclear masses, neutron-capture rates, as well as beta-decay properties. More specifically, beta-decay half-lives and beta-delayed neutron branching ratios depend on an accurate knowledge of the $\beta$-decay strength function. For this reason, $\beta$-decay intensities for 69,71Co were determined using the technique of total absorption spectroscopy at the National Superconducting Cyclotron Laboratory at Michigan State University. This technique allows us to overcome the so-called ``pandemonium effect, which can cause beta-feeding intensities to high-lying excitation energies to be missed in traditional beta-decay studies. The high Q-values of both 69Co and 71Co allow for the study of beta-decay properties over a broad energy range. The resultant beta-decay intensities and deduced Gamow-Teller strength distributions will be presented and compared to theoretical calculations, including QRPA.
Primary authors
Artemis Spyrou
(NSCL/MSU)
Sean Liddick
(NSCL/MSU)
Stephanie Lyons
(National Superconducting Cyclotron Laboratory)
Co-authors
Aaron Couture
(Los Alamos National Laboratory)
Alex Brown
(NSCL/MSU)
Alex Dombos
(NSCL/MSU)
Alicia Palmisano
(NSCL/MSU)
Dr
Ann-Cecilie Larsen
(University of Oslo)
Dr
Ben Crider
(National Superconducting Cyclotron Laboratory)
Chris Prokop
(Los Alamos National Laboratory)
Darren Bleuel
(Lawrance Livermore National Laboratory)
Dr
Farheen Naqvi
(University of Notre Dame)
Georgios Perdikakis
(Central Michigan University)
Lucia Crespo Campo
(University of Oslo)
Prof.
Magne Guttormsen
(Department of Physics, University of Oslo, Norway)
Mallory Smith
(National Superconducting Cyclotron Laboratory)
Matthew Mumpower
(Los Alamos National Laboratory)
Peter Moller
(Los Alamos National Laboratory)
Rebecca Lewis
(NSCL/MSU)
Prof.
Rebecca Surman
(University of Notre Dame)
S Valenta
(Charles University Prague)
Shea Mosby
(Los Alamos National Laboratory)
Stephen Quinn
(NSCL/MSU)
Sunniva Siem
(University of Oslo)
Therese Renstrom
(University of Oslo)
