Nuclear Techniques ›› 2014, Vol. 37 ›› Issue (08): 80502-080502.doi: 10.11889/j.0253-3219.2014.hjs.37.080502


Theoretical investigation on the triggered gamma-ray emission from long-lived isomer in 178Hf

WANG Feipeng1 SHEN Shuifa1,2 YAN Yupeng2   

  1. 1(Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei 230031, China) 2(School of Physics, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand)
  • Received:2014-01-13 Revised:2014-03-28 Online:2014-08-10 Published:2014-07-22

Abstract: Background: 178Hfm2 isomer is considered the most suitable candidate to study the depletion of its stored energy induced by low-energy X-ray in recent decades. Purpose: The aim is to research whether there exist potential gateway states which may trigger gamma-ray emission from the K?=16+ isomer with low-energy photons. Methods: The projected shell model is at first used to study the multi-quasiparticle and collective excitation states of 178Hf. Results: The results show that the 16+ isomer lies well separated in energy from other states. But when the configuration-constrained (diabatic blocking) calculations, with inclusion of ?-deformation, are performed to study the multi-quasiparticle excitation states of 178Hf, it appears that three levels can be the most likely candidates for photodeexcitation of the 16+ isomer. Conclusion: The Potential Energy Surface (PES) calculations in the present work suggest that this nucleus is rigid to axially asymmetric shapes.

Key words: Triggered gamma emission, Multi-quasiparticle states, Potential Energy Surface (PES)