result from neutron-pumping the inversion in situ seems incompatible with maintaining the Mössbauer effect, although there are still avenues to explore.

Heating may be reduced by two-stage neutron-gamma pumping, in which neutron capture occurs in a parent-doped converter, where it generates Mössbauer radiation that is then absorbed by ground-state nuclei in the graser.Two-stage pumping of multiple levels offers