$\beta$-delayed neutron spectroscopy of $^{133}$In

The decay properties of <math><mmultiscripts><mi>In</mi><mprescripts/><none/><mn>133</mn></mmultiscripts></math> were studied in detail at the ISOLDE Decay Station. The implementation of the Resonance Ionization Laser Ion Source allowed separate measurements of its <math><mrow><mn>9</mn><mo>/</mo><msup><mn>2</mn><mo>+</mo></msup></mrow></math> ground state (<math><mmultiscripts><mi>In</mi><mprescripts/><none/><mrow><mn>133</mn><mi>g</mi></mrow></mmultiscripts></math>) and <math><mrow><mn>1</mn><mo>/</mo><msup><mn>2</mn><mo>−</mo></msup></mrow></math> isomer (<math><mmultiscripts><mi>In</mi><mprescripts/><none/><mrow><mn>133</mn><mi>m</mi></mrow></mmultiscripts></math>). With the use of <math><mi>β</mi></math>-delayed neutron and <math><mi>γ</mi></math> spectroscopy, the decay strengths above the neutron separation energy were quantified in this neutron-rich nucleus for the first time. The allowed Gamow-Teller transition <math><mrow><mn>9</mn><mo>/</mo><msup><mn>2</mn><mo>+</mo></msup><mo>→</mo><mn>7</mn><mo>/</mo><msup><mn>2</mn><mo>+</mo></msup></mrow></math> was located at 5.93 MeV in the <math><mmultiscripts><mi>In</mi><mprescripts/><none/><mrow><mn>133</mn><mi>g</mi></mrow></mmultiscripts></math> decay with a <math><mrow><mi>log</mi><mi>f</mi><mi>t</mi><mo>=</mo><mn>4.7</mn><mo>(</mo><mn>1</mn><mo>)</mo></mrow></math>. In addition, several neutron-unbound states were populated at lower excitation energies by the first-forbidden decays of <math><mmultiscripts><mi>In</mi><mprescripts/><none/><mrow><mn>133</mn><mi>g</mi><mo>,</mo><mi>m</mi></mrow></mmultiscripts></math>. We assigned spins and parities to those neutron-unbound states based on the <math><mi>β</mi></math>-decay selection rules, the <math><mrow><mi>log</mi><mi>f</mi><mi>t</mi></mrow></math> values, and systematics.