Beta-decay of 33Mg using Total Absorption Spectroscopy

Low mass X-ray binaries that transiently accrete matter onto their neutron stars are excellent laboratories for studying dense matter physics. These systems alternate between outburst and quiescence phases and monitoring the surface temperatures of neutron stars in quiescence reveals a great deal of information about their structure and composition. But infering these properties requires a complete understanding of different nuclear reactions that heat or cool the crust. Urca cooling is a source of neutrino cooling in the crust that strongly depends on the ground-state to ground-state beta decay transition strengths. The 33Mg - 33Al transition is predicted to be the strongest Urca cooling agent for crusts composed of X-ray burst ashes. This relies partly on the strong ground state branch measured in high-resolution beta-delayed gamma-spectroscopy of 33Mg. However, recent measurements of a negative parity ground state in 33Mg makes this a first forbidden decay and the strong transition strength is questioned in the literature, citing Pandemonium effect as a possible reason. We try to resolve this anomaly using Total Absorption Spectroscopy that is mostly free of this Pandemonium effect. I will present preliminary results from the beta-decay of 33Mg experiment performed at NSCL.