La-139

Reviewed by T. Nakagawa, JAERI, February 2003

# 1. Files

***ENDF/B-VI***: Evaluation was made by Schenter et al. in 1980. Their
data were revised in 1991.

***JENDL-3.3***: In 1984, the evaluation was made by JNDC FPND working
group for JENDL-2. The data were revised in 1990 \[Ka92\] for JENDL-3.1,
in 1993 \[Ka01\] for JENDL-3.2. JENDL-3.3 is almost the same as
JENDL-3.2.

***JEFF-3.0***: JEF-2.2 adopted the data of RCN-3. Resonance parameters
were updated in 1987, and the charged particle emission cross sections
were included in 1989 adopting REAC-ECN-4. JEFF-3.0 is the same as
JEF-2.2.

***CENDL-3***: New evaluation was made in 1999 by Zhao et al. The data
were revised in 2001.

***BROND-2***: No data are given.

# 2. Thermal and resonance region

The resonance parameters are summarized in Table 1.

***ENDF/B-VI***

Resolved resonance parameters were based on the recommendation by
Mughabghab et al. \[Mu73\] Unresolved resonance parameters were not
given.

***JENDL-3.3***

Resolved resonance parameters were evaluated on the basis of Shwe et al.
\[Sh67\], Morgenstern et al. \[Mo69\], Hacken et al. \[Ha76\], Musgrove
et al. \[Mu77\] and Nakajima et al. \[Na83\]

Unresolved resonance parameters were given to reproduce the cross
sections calculated with the CASTHY code in the energy range from 15 to
100 keV.

***JEFF-3.0***

No detailed information is given in the comment part (MF1,MT451).

***CENDL-3***

JENDL-3.2 was adopted. The capture widths of negative resonances at -130
eV were slightly changed. So as to reproduce the capture cross section
of 8.24 at 0.0253 eV \[Mu01\]

Thermal cross sections and resonance integral of capture cross section
are listed in Table 2.

**[Recommendation/conclusion for the thermal and resonance
region]{.underline}**

***JENDL-3.3*** is recommended.

# 3. Fast neutron region

**(1) Methodology**

## ENDF/B-VI

Theoretical calculation was performed using the optical potential of
Moldauer \[Mo63\]. Inelastic scattering cross sections were calculated
with the COMNUC-3 code considering 19 discrete levels. The capture cross
section was calculated with the NCAP code. No threshold reaction cross
sections are given.

The angular distributions of elastically scattered neutrons and those of
inelastic scattering were assumed to be isotropic in the laboratory
system.

Evaporation spectra were given to the continuum inelastic scattering.

## JENDL-3.3

The total, elastic and inelastic scattering, and capture cross sections
were calculated with the spherical optical model and statistical model
code CASTHY. The gamma-ray strength function was determined so as to
reproduce the capture cross section of 38 mb at 30 keV \[Mu78\]. For the
inelastic scattering, 12 levels were considered. The direct/semi-direct
capture was calculated from a simple formula of Benzi and Reffo \[Be69\]

Other reaction cross sections were calculated with the preequilibrium
and multi-step evaporation code PEGASUS. The (n,p) and (n,) reaction
cross sections were normalized to 12 mb recommended by Forrest \[Fo86\]
and 2.5 mb measured by Woelfle et al. \[Wo88\] at 14.5 MeV,
respectively.

Angular distributions of elastic and inelastic scattering were
calculated with the CASTHY code. .

The energy distributions were calculated with the PEGASUS code.

## JEFF-3.0

No detailed information is given in the comment part (MF1,MT451).
Optical model calculation was made by adopting Igarasi potential.
Charged particle emission cross sections were included from REAC-ECN-4
library.

***CENDL-3***

Calculated with SUNF code. Angular and energy distributions are
calculated with SUNF code and DWUCK code.

**(2) Total cross section (MT=1)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt1)La139.htm#mt1
and Fig. A1

***JENDL-3.3***, ***JEFF-3.0*** and ***CENDL-3*** are almost the same,
and in agreement with experimental data.

**(3) Capture cross section (MT=102)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt102)La139.htm#mt102
and Fig. A2

JENDL-3.3 is a little bit too large in the energy range from 200 keV to
1.5 MeV. ***CENDL-3*** reproduces best the experimental data.

**(4) Elastic scattering cross section (MT=2)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt2)La139.htm#mt2

**(5) Inelastic scattering cross section (MT=4, 51 -- 91)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt4)La139.htm#mt4

Discrete levels considered in the evaluations are as follows:

ENDF/B-VI 19 levels up to 1.559 MeV (several hypothetical levels are
included)

JENDL-3.3 12 levels up to 1.6831 MeV

JEFF-3.0 23 levels up to 1.943 MeV

CENDL-3 11 levels up to 1.5584 MeV

Direct inelastic was considered in the evaluations for ***CENDL-3***.
The shape of ENDF/B-VI is not reasonable.

**(6) (n,2n) reaction cross section (MT=16)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt16)La139.htm#mt16

**(7) (n,p) reaction cross section (MT=103)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt103)La139.htm#mt103

**(8) (n,) reaction cross section (MT=107)**

See Fig:
[http://www.nndc.bnl.gov/sg21/fp21/htm/](http://www.nndc.bnl.gov/sg21/fp21/htm/La139.htm#mt107)La139.htm#mt107

**(9) Other reactions**

The following reaction cross sections are given:

ENDF/B-VI no threshold reactions

JENDL-3.3 (n,3n), (n,n), (n,np), (n,nd), (n,nt), (n,d), (n,t), (n,^3^He)

JEFF-3.0 (n,d), (n,t), (n,^3^He), (n,2p)

CENDL-3 (n,3n), (n,n), (n,np), (n,d), (n,t), (n,^3^He)

**[Recommendation/conclusion for the fast energy region]{.underline}**

***CENDL-3*** is recommended.

# References

\[Al73\] Alian A. et al.: *J. Radioanal. Chem.*, **15**, 535 (1973)
EXFOR20644.

\[Be69\] Benzi V. and Reffo G.: *CCDN-NW/*10 (1969).

\[De71\] De Corte F. et al.: *J. Radioanal. Chem.*, **9**, 9 (1971)
EXFOR20646.

\[Fo86\] Forrest R.A.: *AERE-R* 12419 (1986).

\[Gl75\] Gleason G.: *Radiochem. Radioanaly. Lett.*, **23**, 317 (1975)
EXFOR10644.

\[Ha76\] Hacken G. et al.: *Phys. Rev.*, **C13**, 1884 (1976).

\[He78\] Heft R.E.: 78Mayag, 495 (1978) EXFOR12866.

\[Ka92\] Kawai M. et al.: *J. Nucl. Sci. Technol.*, **29**, 195 (1992).

\[Ka01\] Kawai M. et al.: *J. Nucl. Sci. Technol.*, **38**, 261 (2001).

\[Ma75\] Mannhart W.: *Z. Phys.*, **A272**, 273 (1975) EXFOR20610.

\[Mo63\] Moldauer P.A.: *Nucl. Phys.*, **47**, 65 (1963).

\[Mo69\] Morgenstern J. et al.: *Nucl. Phys.*, **A123**, 561 (1961).

\[Mu73\] Mughabghab S.F. and Garber D.I.: *BNL*-325 3rd Edition (1973).

\[Mu77\] Musgrove A.R. de L. et al.: *Aust. J. Phys.*, **30**, 599
(1977).

\[Mu78\] Musgrove A.R. de L. et al.: 78Harwell, 449 (1978).

\[Mu81\] Mughabghab S.F. et al.: *Neutron Cross Sections, Vol. 1, part
A*, Academic press (1981).

\[Mu01\] Mughabghab S.F.: *INDC(NDS)*-424, p.69 (2001)

\[Na83\] Nakajima Y. et al.: *J. Nucl. Sci. Technol.*, **20**, 183
(1983).

\[Ry71\] Ryves T.B. et al.: *J. Nucl. Energy*, **25**, 129 (1971)
EXFOR20791.

\[Sh67\] Shwe H. et al.: *Phys. Rev.*, **159**, 1050 (1967).

\[St72\] Steinnes E.: *J. Inorg. Nucl. Chem.*, **34**, 2699 (1972)
EXFOR20188.

\[St75\] Steinnes E.: *J. Inorg. Nucl. Chem.*, **37**, 1591 (1975)
EXFOR20635.

\[Ta78\] Takiue M. et al.: *Nucl. Instrum. Methods*, **148**, 157 (1978)
EXFOR20853.

\[Va74\] Van der Linden R. et al.: *J. Radioanal. Chem.*, **20**, 695
(1974) EXFOR20645.

\[Wo88\] Woelfle R. et al.: *Appl. Radiat. Isot.*, 39, 497 (1988).

Table 1 Summary for Resolved and Unresolved Resonance Region: La-139

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

Library RRP URP Remarks

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

ENDF/B-VI 9.0293 keV, SLBW No URP

JENDL-3.3 15 keV, MLBW 100 keV

JEFF-3.0 10.801 keV, MLBW 250 keV

CENDL-3 15 keV, MLBW 100 keV almost the same as JENDL-3.2

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

Table 2 Thermal Cross Sections and Resonance Integral: La-139

Unit: barns

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

Library/Experiment Total Elastic Capture Res.Integ.

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

ENDF/B-VI 21.447 12.452 8.995 12.0

JENDL-3.3 19.060 10.130 8.930 11.7

JEFF-3.0 19.443 10.512 8.931 11.9

CENDL-3 18.371 10.130 8.241 11.5

Mughabghab et al. \[Mu81\] \-- 10.130.22 8.930.04 11.80.8

Mughabghab \[Mu01\] \-- \-- 8.240.05 \--

(Experimental data reported after 1970)

De Corte et al. \[De71\] 11

Ryves et al. \[Ry71\] 9.030.33

Steinnes \[St72\] 11.81.2

Alian et al. \[Al73\] 17.1

Van der Linden et al. \[Va74\] 11.60.7

Gleason \[Gl75\] 9.150.25^\*1^ 12.50.4

Mannhart \[Ma75\] 8.9330.036

Steinnes \[St75\] 11.20.5

Takiue et al. \[Ta78\] 8.630.34^\*1^

Heft \[He78\] 12.60.6

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

\*1 Maxwellian average

![](media/image1.wmf){width="8.0in" height="6.654166666666667in"}

Fig. A1 La-139 total cross section

![](media/image2.wmf){width="8.036805555555556in"
height="6.654166666666667in"}

Fig. A2 La-139 capture cross section