233 U EVALUATION IN THE RESOLVED AND UNRESOLVED

233 U EVALUATION IN THE RESOLVED AND UNRESOLVED RESONANCE RANGE Nuclear Data Group Nuclear Science and Technology Division Oak Ridge National Laboratory L. C. LEAL and H. DERRIEN International Atomic Energy Agency Second Research Coordination Meeting Evaluated Nuclear Data for Th-U Fuel Cycle December 6 -9, 2004 IAEA Headquarters, Vienna, Austria

Evolution of the 233 U Evaluation · R-Matrix evaluation done by Moore, Reich and Vogt below 12 e. V; · Evaluation extended up to 60 e. V by Bergen and Silbert; · Reynolds and Steiglitz used least squared fitting code MULTI; · G. de Saussure converted the Reich-Moore parameters to Adler-Adler parameters (ENDF/B-V and ENDF/B-VI); · Derrien performed SAMMY Reich-Moore evaluation up to 150 e. V (JENDL); OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 2

233 U Resolved Resonance Evaluation Features: · Five transmission, seven fission cross section and one capture cross section data measurements were used in the evaluation. · Evaluation performed up 600 e. V with 769 resonances with 738 in the energy range analyzed and 31 external resonances. · SAMMY: Reich-Moore formalism was used. (Evaluation combined differential and integral data) OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 3

Selected Differential Measurements Author Energy Region Analyzed Features (e. V) Moore at al. , 1960 0. 020 – 15. 0 Transmission, TOF 15. 7 m Pattenden and Harvey, 1963 0. 080 – 15. 0 Transmission, TOF 45 m Weston et al. , 1968 1. 0 – 600. 0 Simultaneous Capture and Fission, TOF 25. 6 m Weston et al. , 1968 0. 020 – 1. 0 Simultaneous Capture and Fission, TOF 25. 6 m Blons, 1973 4. 0 – 600. 0 Fission, TOF 50. 1 m Deruyter and Wagemans, 1974 0. 020 – 15. 0 Fission, TOF 8. 1 m Harvey et al. , 1979 0. 020 – 1. 2 Transmission, TOF 17. 9 m Wagemans e al. , 1988 0. 002 – 1. 0 Fission, TOF 8. 1 m Guber et al. , 1998 0. 5 – 700 Fission, TOF 80 m Temperature (two sets) Guber et al. , 1998 OAK RIDGE NATIONAL LABORATORY 1. 0 – 700. 0 Transmission, TOF 80 m, Temperature 11 K (two sets) U. S. DEPARTMENT OF ENERGY 4

Comparison of ORNL 233 U fission cross sections measurement and ENDF/B-VI data OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 5

Evaluated Integral Quantities Quantity ENDF/B-VI Axton Standard BNL ga 0. 9996 ± 0. 0011 0. 9995 ± 0. 0011 gf 0. 9955 ± 0. 0014 0. 9955 ± 0. 0011 0. 99996 ± 0. 0011 Ia 897 ± 20 If 760 ± 17 K 1 742. 60 ± 2. 40 742. 25 ± 2. 37 738 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 6

Code SAMMY · Resolved Resonance Range: R-Matrix Formalism · Unresolved Resonance Range: Based on FITACS code · Uses Generalize Bayes’ Equation OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 7

Total and Fission Cross Sections of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 8

Capture and Fission Cross Sections of Weston et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 9

Total and Fission Cross Sections of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 10

Total and Fission Cross Sections of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 11

Total and Fission Cross Sections of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 12

Fission Cross Sections of Guber et al. and Blons et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 13

Thermal Fission and Capture Cross Sections of Weston et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 14

Thermal Cross Sections (0. 0253 e. V) Data Axton Standard ORNL Evaluation Fission ENDF/B-VI Standard 531. 14 ± 1. 33 530. 70 ± 1. 34 530. 70 Capture 45. 51 ± 0. 68 45. 52 ± 0. 70 45. 52 Scattering 12. 13 ± 0. 66 12. 19 ± 0. 67 12. 18 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 15

Integral Quantities · Westcott Factor · K 1 Factor · Resonance Integral · α Ratio OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 16

Evaluated Integral Quantities Quantity ENDF/B-VI Axton Standard BNL ORNL ga 0. 9996 ± 0. 0011 0. 9995 ± 0. 0011 1. 00325 gf 0. 9955 ± 0. 0014 0. 9955 ± 0. 0011 0. 9996 ± 0. 0011 1. 00045 Ia 897 ± 20 917. 45 If 760 ± 17 777. 82 738 746. 77 K 1 742. 60 ± 2. 40 742. 25 ± 2. 37 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 17

233 U Unresolved Resonance Evaluation · Brief Overview of the Resonance Formalism used in the Evaluation: - Unresolved Formalism - Houser-Feshbach - Single-Level Breit Wigner Average Cross Section Experimental Data Base and Computational Tools (SAMMY) ·Evaluation Procedures ·Applications OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 18

Cross Section Formalism Hauser-Feshbach (HF) Average Cross Section a is the incident channel; b is the exit channel (gamma or fission); νc degrees of freedom; Tc transmission coefficient for channel c OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 19

Cross Section Formalism (cont’d) Single-Level Breit-Wigner (SLBW) Cross Section The energy average of the SLBW cross section is OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 20

Cross Section Formalism (cont’d) The average SLBW cross section: HF and SLBW are equivalent when Note: The relation between HF and SLBW is not well described in the ENDF manual OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 21

Evaluation Procedure: I. Experimental Data Base Average total cross section of Guber obtained from transmission measurements done at the 80 -meter flight-path of the Oak Ridge Electron Linear Accelerator (ORELA); Fission cross section measurement by Guber done at the 80 -meter flight-path of ORELA; Weston capture cross section data derived from α measurements (capture-to-fission ratio) performed at RPI. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 22

INPUT PARAMETERS FOR SAMMY Average Resonance Parameters Obtained from the Resolved Resonance Region (below 600 e. V) were used to analyze the 233 U cross sections in the unresolved resonance region from 600 e. V to 40 ke. V Parameters of the SAMMY fit of the experimental data in the energy region 600 e. V to 40 ke. V l=0 l=1 l=2 R’ 9. 725 7. 733 8. 635 Dist. Level Parameters Strength function x 104 -0. 162 0. 076 -0. 032 0. 0946 1. 767 0. 0725 <Γ > 39. 0 26. 0 39. 0 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 23

Few Average Angular Resonance Parameters for l=0 And Resonance Spin J=3 (units are e. V) Reference Energy 6. 0000 E+02 6. 8250 E+02 7. 6500 E+02 8. 7250 E+02 9. 9000 E+02 1. 1250 E+03 1. 2500 E+03 1. 3400 E+03 1. 4100 E+03 1. 4700 E+03 1. 5850 E+03 1. 7350 E+03 1. 8800 E+03 2. 1075 E+03 2. 5225 E+03 3. 1200 E+03 <D> 1. 2164 E+00 1. 2162 E+00 1. 2160 E+00 1. 2157 E+00 1. 2154 E+00 1. 2151 E+00 1. 2148 E+00 1. 2146 E+00 1. 2145 E+00 1. 2143 E+00 1. 2140 E+00 1. 2137 E+00 1. 2133 E+00 1. 2128 E+00 1. 2118 E+00 1. 2104 E+00 < n 0> 1. 1424 E‑ 04 1. 4227 E‑ 04 1. 1140 E‑ 04 1. 4593 E‑ 04 9. 8628 E‑ 05 1. 2135 E‑ 04 1. 0382 E‑ 04 1. 4378 E‑ 04 9. 8879 E‑ 05 1. 2907 E‑ 04 1. 1007 E‑ 04 1. 1576 E‑ 04 1. 2721 E‑ 04 1. 1253 E‑ 04 1. 2347 E‑ 04 1. 1315 E‑ 04 < > 3. 9010 E‑ 02 3. 9012 E‑ 02 3. 9013 E‑ 02 3. 9015 E‑ 02 3. 9017 E‑ 02 3. 9019 E‑ 02 3. 9022 E‑ 02 3. 9023 E‑ 02 3. 9024 E‑ 02 3. 9025 E‑ 02 3. 9027 E‑ 02 3. 9030 E‑ 02 3. 9033 E‑ 02 3. 9036 E‑ 02 3. 9044 E‑ 02 3. 9054 E‑ 02 < f> 7. 7530 E‑ 01 7. 6948 E‑ 01 7. 5590 E‑ 01 7. 7264 E‑ 01 7. 4994 E‑ 01 7. 7074 E‑ 01 7. 5375 E‑ 01 7. 8066 E‑ 01 7. 4507 E‑ 01 7. 7283 E‑ 01 7. 5222 E‑ 01 7. 5964 E‑ 01 7. 6761 E‑ 01 7. 6345 E‑ 01 7. 5709 E‑ 01 7. 4329 E‑ 01 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 24

Comparisons of Average Cross Sections Calculated with SAMMY with Experimental Data: bottom curve is the average fission cross section and upper curve is the average total cross sections of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 25

Comparisons of Average Experimental Total Cross Sections of Poenitz (two data sets) and ORNL data of Guber et al. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 26

Comparisons of ENDF/B-VI Average Total Cross Section (—) with Experimental Data of Poenitz ( ) and ORNL data of Guber * et al. (o) OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 27

Concluding Remarks New 233 U unresolved resonance evaluation including high resolution transmission data and fission cross section data taken at ORELA; SAMMY code was used to evaluate both the resolved and unresolved resonance region (consistency); Evaluation very well documented; In the resolved energy region the evaluation was performed with the Reich-Moore formalism up to 600 e. V; In the unresolved energy region (600 e. V to 40 ke. V) the evaluation was done using the SLBW formalism (only format permitted in ENDF); level-level interference effects in the fission cross sections not included; Evaluation accepted for inclusion in the US Evaluated Nuclear Data Files (ENDF) OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 28

How about other isotopes ? ? U-232 Maslov Evaluation vs ENDF/B-VII U-234 Maslov Evaluation U-236 ENDF/B-VII, JENDL 3. 3 Pa-231 Maslov Evaluation Pa-233 Maslov Evaluation + Morogovskij OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 29