The Latest Total Absorption Results from MTAS

Measuring accurate total $\beta$-feeding patterns is important for understanding reactor decay heat, reactor antineutrino production, and to the freeze out component of the r process in relation to the relative abundances of elements in the galaxy. Total $\beta$-feeding patterns include all decay branches, including ground-state to ground-state decay, feeding to excited states, and $\beta$-delayed neutron branches. Over the last decade measuring $\beta$-feeding patterns using total absorption spectroscopy has become an important complement to high precision $\gamma$ measurements. Total absorption spectroscopy involves detectors with extremely high efficiency which minimizes beam-time use and overcomes the pandemonium effect in order to extract total $\beta$-feeding patterns for nuclei abundantly produced in nuclear fission. It also allow extraction of the ground-state to ground-state feeding and $\beta$-delayed neutron branches. The Modular Total Absorption Spectrometer (MTAS) is the worlds largest total absorption spectrometer that is capable of extracting total $\beta$-feeding patterns. We will present new results of several nuclei that were measured at the HRIBF at Oak Ridge National Laboratory and at Argonne National Laboratory.