Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE)

Very neutron rich nuclei decay almost exclusively by β[beta] decay followed by the emission of a delayed neutron. The Versatile Array of Neutron Detectors at Low Energy(VANDLE) measures the energy of neutrons emitted after beta decay using the time of flight(TOF) technique. This work studied beta-delayed neutron emission in the region of the doubly magic nucleus ¹³²Sn[132Sn] using an upgraded version of VANDLE to better determine the properties of neutron rich nuclei. These properties are important for nuclear structure models, nuclear energy and security, as well as the astrophysical rapid neutron capture process which occurs in this region. The experimental campaign took place in the spring of 2015 at Argonne National Laboratory, using beams from the Californium Rare Isotope Breeder Upgrade(CARIBU) facility, and measured multiple isotopes. The results for two of these isotopes will be presented in this work, ¹³⁵Sb[135Sb] and ¹³⁶Sb[136Sb].