Total absorption spectroscopy of the Z<20 neutron-rich nuclei

FRIB Decay Station Initiator was implemented to study the decay of neutron-rich isotopes near doubly magic 54Ca. The two-focal plane arrangement of the FDSi enabled complementary measurement of beta decay strength distributions using high-resolution gamma-ray, neutron time-of-flight, and total absorption spectroscopy detection techniques [Cox24]. For the first time, the total absorption spectroscopy was performed on nuclei in this region of the nuclear chart. We used a decay of 49K to benchmark the performance of the detection system and searched for gamma-ray decay from neutron unbound states. The analysis results for the decay of potassium isotopes will be presented.