Using the data which we've sorted to date, I looked into the gamma-gamma coincidences and have identified a number of nuclei e.g. 50Cr, 52Mn, 55Fe which would be consistent with fusion-evaporation reactions involving the sulphur-32 projectiles and aluminium-27. Such reactions would yield a 59Cu comound system and these channels would be populated as a result of the evaporation of a combination of alphas, protons and neutrons.
These lines are intense and the conicdences are very clear and clean. I think this suggests that the beam is hitting some aluminium components within the plunger chamber. This could be the plunger vessel itself or the target frame perhaps.
There is another interesting observation: some of the identified transitions are emitted from levels which have sub-ps lifetimes. At this plunger distance, we might expect these lines to be fully Doppler shifted as they would decay in-flight well in advance of reaching the stopper. Yet, we observe these lines with their non-Doppler shifted energies suggesting that they are not being emitted in-flight but rather at rest. This might suggest that the 32S+27Al reactions are taking place within some thick piece of aluminium. Some of the lines show signs of having been shifted in energy to some extent which might indicate that not all of the ions are completely stopped. The observed lineshapes seem to be consistent with the short-lived states showing evidence of Doppler shift while the decay of the "longer-lived" states (~9 ps) are very sharp.
I haven't slept for about 24 hours so I may be talking absolute sh*te (famous Scottish word). |