<p>Gamma-spectra recorded on 03/06/2019, 24/06/2019, and 05/08/2019 analysed for identifyiing isotopes produced and estimating their activities. The spectra are shown in attached pictures with the identified peaks labelled.</p>
<p>Ta179 activity given here was calculated by analysing the 61 keV peak assuming that this peak would be dominated by X-rays from Hf175 and and Ta179 (as these isotopes have at least 3 orders of magnitude larger activity than any other isotope). With that assumption, and by using the value for Hf175 activity (1.12E+04 on 5 Aug) that was calculated using its gamma peaks, the value of Ta179 activity on 5 Aug was estimated to be 1.81E+04 kBq.</p>
<p>A summary of most active isotopes at the time of shipment (around 24 Dec 2019) is shown in table below:</p>
<table border="1" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td> </td>
<td> </td>
<td>73 d since irr</td>
<td> </td>
<td>7 mnths since irr</td>
</tr>
<tr>
<td>Isotope</td>
<td>halflife (d)</td>
<td>Activity on 05 Aug (kBq)</td>
<td>error (kBq)</td>
<td>Activity on 24Dec (kBq)</td>
</tr>
<tr>
<td>179Ta</td>
<td>664.3</td>
<td>1.81E+04</td>
<td>>200</td>
<td>1.55E+04</td>
</tr>
<tr>
<td>177Ta</td>
<td>56.56</td>
<td>undetermined</td>
<td> </td>
<td> </td>
</tr>
<tr>
<td>175Hf</td>
<td>70</td>
<td>1.12E+04</td>
<td>14.16</td>
<td>2.80E+03</td>
</tr>
<tr>
<td>179Hf</td>
<td>25.05</td>
<td>1.45E+01</td>
<td>0.91</td>
<td>3.01E-01</td>
</tr>
<tr>
<td>181Hf</td>
<td>42.39</td>
<td>1.68E+01</td>
<td>0.97</td>
<td>1.71E+00</td>
</tr>
<tr>
<td>172Lu</td>
<td>6.7</td>
<td>4.61E+00</td>
<td>0.50</td>
<td>2.36E-06</td>
</tr>
<tr>
<td>173Lu</td>
<td>485.45</td>
<td>3.55E+01</td>
<td>6.06</td>
<td>2.90E+01</td>
</tr>
<tr>
<td>174Lu</td>
<td>142</td>
<td>undetermined</td>
<td> </td>
<td> </td>
</tr>
<tr>
<td>177Lu</td>
<td>6.65</td>
<td>undetermined</td>
<td> </td>
<td> </td>
</tr>
<tr>
<td>88Zr</td>
<td>83.4</td>
<td>5.04E+00</td>
<td>1.04</td>
<td>1.57E+00</td>
</tr>
<tr>
<td>88Y</td>
<td>106.63</td>
<td>6.90E-01</td>
<td>0.18</td>
<td>2.78E-01</td>
</tr>
<tr>
<td>95Nb</td>
<td>34.99</td>
<td>5.11E+00</td>
<td>0.40</td>
<td>3.19E-01</td>
</tr>
<tr>
<td>57Co</td>
<td>271.74</td>
<td>1.23E+01</td>
<td>1.78</td>
<td>8.57E+00</td>
</tr>
<tr>
<td>58Co</td>
<td>70.86</td>
<td>7.32E-01</td>
<td>0.25</td>
<td>1.86E-01</td>
</tr>
<tr>
<td>65Zn</td>
<td>243.93</td>
<td>5.71E+00</td>
<td>0.69</td>
<td>3.84E+00</td>
</tr>
<tr>
<td>54Mn</td>
<td>312.2</td>
<td>2.63E+00</td>
<td>0.30</td>
<td>1.93E+00</td>
</tr>
<tr>
<td>Total</td>
<td> </td>
<td>2.94E+04</td>
<td> </td>
<td>1.83E+04</td>
</tr>
</tbody>
</table> |