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of four independent HPGe n-type crystals in a common cryostat. The two Clovers were placed face to face, in contact with a 5.2 mm thick sample holder, correspond- ing nearly to a 4 π geometry. The sample position in the very center of the system could be reproduced within ± 0.1 mm. The whole assembly was shielded against room background with 10 cm of lead and a 5 mm thick layer of copper. The data from the eight Ge crystals of the two Clover detectors were processed by separate analog to digital converters (ADCs) and could, therefore be an- alyzed independently. In Clover measurements, the con- tributions of the eight crystals were added to represent the total number of events per γ -ray line. The efficiency calibration of the Clover system was carried out with a set of weak reference sources. 

The total amount of activated nuclei N$_{act}$ at the end of each irradiation can be deduced from the number of events C in a particular γ -ray line registered in the HPGe detector during the measuring time t$_{m}$ [20], 

where t$_{w}$ denotes the waiting time between irradiation and activity measurement, ε$_{γ}$ the efficiency of the HPGe 

## III. DATA ANALYSIS 

## A. General procedure 

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detector, and I$_{γ}$ the relative γ intensity per decay of the respective transition. K is a correction factor which is either the self-absorption correction factor K$_{γ}$ (Eq 2) or the total correction factor K$_{tot}$ (Table IV). The decay properties of the investigated product nuclei are summa- rized in Table III. 

The large distance between sample and detector in the measurements with the single HPGe detector allowed us to calculate the correction for γ -ray self-absorption from the expression for disk samples of thickness d [20], 

using the γ -ray absorption coefficients µ from Ref. [33]. This correction factor was negligible for the thin (10- 30 µ m) gold foils. 

The close geometry of the Clover detectors required a more elaborate treatment of the sample-related correc- tions in the measurement of the small activities of $^{103}$Pd and $^{133}$Ba$^{g}$. The correction factors K ′ γ for γ -ray self ab- sorption, K$_{E}$ for the extended geometry of the sample, and K$_{S}$ for the summing effect of cascade transitions have the been calculated by means of Monte Carlo simulations with the GEANT4 toolkit [34] and a detailed computer model of the setup [26] (Table IV). The summing correc- 

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