Decay of low-lying 12C resonances within a 3alpha cluster model

TL;DR

This paper models the decay of low-lying 12C resonances into three alpha particles using a 3alpha cluster approach, revealing how decay mechanisms change with distance and employing complex scaling for accurate continuum wave functions.

Contribution

It introduces a detailed computational approach combining hyperspherical adiabatic expansion and complex scaling to analyze 12C resonance decays.

Findings

Decay mechanisms differ between states, with direct decay dominating in 1+ resonances.

Sequential decay is prominent in 3- resonances.

Accurate large-distance wave functions are essential for understanding decay processes.

Abstract

We compute energy distributions of three $\alpha$-particles emerging from the decay of $^{12}$C resonances by means of the hyperspherical adiabatic expansion method combined with complex scaling. The large distance continuum properties of the wave functions are crucial and must be accurately calculated. The substantial changes from small to large distances determine the decay mechanisms. We illustrate by computing the energy distributions from decays of the $1^{+}$ and $3^-$-resonances in $^{12}$C. These states are dominated by direct and sequential decays into the three-body continuum respectively.