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arXiv · 1805.07901

Stability of the linear chain structure for $^{12}$C in covariant density functional theory on a 3D lattice

Z. X. Ren·S. Q. Zhang·P. W. Zhao·N. Itagaki·J. A. Maruhn·J. Meng
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Abstract

The stability of the linear chain structure of three $\alpha$ clusters for $^{12}$C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three $\alpha$ initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of $\sim$2.0 MeV to $\sim$2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency $\sim$3.5 MeV, but the fission still occurs when the rotational frequency approaches to $\sim$4.0 MeV.

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Z. X. Ren, S. Q. Zhang, P. W. Zhao, N. Itagaki, J. A. Maruhn, J. Meng. 2018-05-21. Stability of the linear chain structure for $^{12}$C in covariant density functional theory on a 3D lattice. https://doi.org/10.1007/s11433-019-9412-3

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