New Mechanism of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>α</mml:mi></mml:math>-Particle Production in Heavy-Ion-Induced Fission

Abstract

Detailed studies have been made of the multiplicity, energy, and angular distributions of $\ensuremath{\alpha}$ particles emitted in coincidence with fission fragments from the $^{165}\mathrm{Ho}$ + $^{56}\mathrm{Fe}$ (${E}_{\mathrm{lab}}=465$ MeV) reaction. Approximately 90% of the $\ensuremath{\alpha}$ particles are evaporated from the two fully accelerated fission fragments. The remaining $\ensuremath{\alpha}$ particles have a strongly enhanced emission probability in the direction perpendicular to the scission axis, suggesting the contact or neck region between the fragments as the source of these particles.