Shape Of C-13 Studied By The Real-Time Evolution Method

Background: Recently, Bijker et al. [Phys. Rev. Lett. 122, 162501 (2019)] explained the rotation-vibration spectrum of C-13 by assuming a triangular nuclear shape with D'(3h) symmetry.Purpose: The purpose of this work is to test the shape and symmetry of C-13 based on a microscopic nuclear model without assumption of nuclear shape.Method: We have applied the real-time evolution method to C-13. By using the equation-of-motion of clusters, the model describes the 3 alpha + n system without any assumption of symmetry.Results: REM described the low-lying states more accurately than the previous cluster model studies. The analysis of the wave functions showed that the ground band has approximate triangular symmetry, while the excited bands deviate from it.Conclusion: This work confirmed that the ground band has the intrinsic structure with the triangular arrangement of three alpha particles.