Energy Determinations in Medium and Heavy Nuclei
The problem of energy determinations in nuclear reactions has been discussed in each of the three preceeding mass conferences. Perhaps the only justification for another such talk is found in the fact that the new generation of cyclotrons and their associated equipment provided a wide variety of beams at considerably higher energies and really quite good resolutions. Further, in some laboratories this good resolution is matched to the resolving power of a reaction products analysis system. The available energy permits the study of reactions having large negative Q-values and large Coulomb barriers, such as (α,t) and (α,6He), and the acceleration of heavy ions with a high energy per nucleon opens up the possibility of mass determinations far from the region of stability. New techniques of instrument calibration are required since the old standard 210Po(α) and threshold measurements are no longer suitable. Further, the available accuracy suggests that the effects of electron binding energies, thermal motions of the target nuclei, and target thickness should be re-explored. In fact it is time to ask once again what the measured Q-value determines.
KeywordsLine Shape Heavy Nucleus Target Nucleus Target Thickness Atomic Electron
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