[WPEC SG21: Assessment of Neutron Cross-Section Evaluations for the Bulk
of Fission Products]{.underline}

> 59-Pr-143 Review

Pavel Oblozinsky, BNL, August 2003

### **1. General**

### 

### **Properties:** Unstable nucleus, half-life T~1/2~ = 13.57 d.

### 

**EXFOR data**

Complete lack of experimental data.

### **Evaluations**

ENDF/B-VI Year of origin 1974, by Schenter & Schmittroth (ORNL).

JEF-2 Taken from ENDF/B-VI.

BROND-2 None.

JENDL-3 Year of origin 1990, by JNDC FP Working Group.

CENDL-3 None.

### **2. Thermal and resonance region**

For summary, see Table 1 and 2.

**ENDF/B-VI**

-   No resonance parameters given due to complete lack of experimental
    data.

**JEF-2**

-   Taken from ENDF/B-VI (1974 evaluation by Schenter & Schmittroth)

**JENDL-3**

-   No resonance parameters due to complete lack of experimental data.

-   Unresolved resonance region 4 eV -- 100 keV.

**Recommendation/Conclusion**

The most recent evaluation is that of JENDL-3. **JENDL-3 is
recommended**.

**[3. Fast neutron region]{.underline}**

#### ENDF/B-VI methodology

-   Dates back to 1974, evaluation taken over from ENDF/B-V.

-   Simple statistical model, Moldauer OM parameterization.

#### JENDL-3 methodology

-   Above 100 keV spherical optical model and statistical model code
    CASTHY used.

-   Pre-equilibrium effects included using code PEGASUS.

-   Angular distributions are provided, either based on CASTHY or
    considered isotropic.

##### JEF-2 methodology

-   Taken over from ENDF/B-VI (1974 evaluation by Schenter &
    Schmittroth).

**Comparison of evaluations**

-   MT=1 In view of complete lack of experimental data all evaluations
    look reasonable.

-   MT= 4 JENDL-3 has standard shape, ENDF/B-VI and JEF-2 look
    unrealistic.

-   MT=16 Available only in JENDL-3.

-   MT=102 Complete lack of experimental data, all evaluations look
    reasonable.

-   MT=103 JENDL-3 and JEF-2 equivalent, no data in ENDF/B-VI.

-   MT=107 JENDL-3 and JEF-2 equivalent, no data inENDF/B-VI.

###### Recommendation/Conclusion

> JENDL-3 is based on up-to-date methodology, and it is fairly complete.
> There are no isotopic experimental data, hence partial comparison is
> possible only, with data measured on natural target (Pr-141, 100%
> abundance). **JENDL-3 is recommended**.

Table 1. Thermal cross sections, resonance integral and one-group
capture values for Pr-143.

+----------------+-------+--------+-------+--------------+-----------+
| **\            | #     | # C    | # El  | # Re         | #         |
| Source**       | Total | apture | astic | sonance Capt | One-group |
|                |       |        |       | ure Integral |           |
|                | **(ba | **(b   | **(ba |              | # Capture |
|                | rn)** | arn)** | rn)** | **(barn)**   |           |
|                |       |        |       |              | **(barn)  |
|                |       |        |       |              | \[1\]**   |
+----------------+-------+--------+-------+--------------+-----------+
| #              | #     | #      | #     | # 4.09E-1    |           |
|  ENDF/B-VI89.0 |  89.0 |        | 190.3 |              |           |
+----------------+-------+--------+-------+--------------+-----------+
| JEF-2          | 89.0  | 89.0   |       | 190.3        | 4.08E-1   |
+----------------+-------+--------+-------+--------------+-----------+
| JENDL-3        | 92.9  | 90.0   | 2.9   | 185          | 1.26E-1   |
+----------------+-------+--------+-------+--------------+-----------+

**Table 2**. Summary of resolved and unresolved resonance region for
Pr-143.

<table style="width:100%;">
<colgroup>
<col style="width: 14%" />
<col style="width: 0%" />
<col style="width: 8%" />
<col style="width: 0%" />
<col style="width: 14%" />
<col style="width: 0%" />
<col style="width: 14%" />
<col style="width: 0%" />
<col style="width: 13%" />
<col style="width: 0%" />
<col style="width: 33%" />
</colgroup>
<tbody>
<tr class="odd">
<td><strong>Library</strong></td>
<td colspan="2"><strong>Year</strong></td>
<td colspan="2"><strong>First Author<br />
</strong></td>
<td colspan="2"><strong>RRR<br />
</strong></td>
<td colspan="2"><h1 id="urr">URR</h1></td>
<td colspan="2"><strong>Remarks</strong></td>
</tr>
<tr class="even">
<td>ENDF/B-VI1974</td>
<td colspan="2">Schenter</td>
<td colspan="2">None</td>
<td colspan="2"><h1 id="section-5"> </h1></td>
<td colspan="2">No resonance parameters given.</td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>JEF-2</td>
<td colspan="2">1974</td>
<td colspan="2">Schenter</td>
<td colspan="2">None</td>
<td colspan="2"><h1 id="section-6"></h1></td>
<td colspan="2">Taken from ENDF/B-VI.</td>
</tr>
<tr class="even">
<td colspan="2">JENDL-3</td>
<td colspan="2">1990</td>
<td colspan="2"><p>JNDC FP</p>
<p>Work. Group</p></td>
<td colspan="2">None</td>
<td colspan="2">4 eV – 100 keV</td>
<td>New evaluation, no resonance parameters given.</td>
</tr>
</tbody>
</table>

#### References

1.  H. Gruppelaar et al, Status of pseudo-fission-product cross sections
    for fast reactors, Final Report of Subgroup 17, Report NEA/WPEC-17,
    ECN-R-98-014 (NEA, Paris, 1998). Recalculated systematically for all
    211 FP and all 5 evaluated libraries by I. Sirakov (BNL, 2002), see
    <http://www.nndc.bnl.gov/sg21/nucl/acs/accs.htm>.