a study was undertakenat the BNM-La

a study was undertaken
at the BNM-Laboratoire National Henri Becquerel in France
and the results obtained with 65Zn sources have been presented.
With the use of a commercial apparatus, quantitative
freeze-dried sources were successfully prepared with an improvement
of the crystallization homogeneity in comparison
to the conventional method. Also, better detection efficiencies
to the electron emission of 65Zn were achieved that confirm
the results obtained in the past [De Sanoit et al., 2004].
In Branger et al. [2008] experiments, contrary to the study
by De Sanoit et al. [2004], no pre-cooling step was applied
at atmospheric pressure, allowing a significant decrease
in the time to freeze the sources (roughly less than 1 min),
depending on the deposited drop mass and the drop spreading.
The cooling and subsequent freezing of the radioactive
deposit were due to self-evaporation under reduced pressure.
The chamber pressure was lowered to 1 Pa during the sublimation
phase to obtain a complete solidification of the unfrozen
mixture. The additional experiments have shown that