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72-Hf-176 NAIG+ EVAL-JAN05 G. NOGUERE (CAD)
DIST-JAN09 20090105
----JEFF-311 MATERIAL 7231
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
******************************************************************
***************************** JEFF-3.1 *************************
** **
** Original data taken from: JENDL-3.3 + New eval. **
** **
******************************************************************
HISTORY
==============================------------------------------------
89-07 JENDL-3 New evaluation was made by K.Hida, T.Yoshida (naig)
and K.Shibata (jaeri).
94-01 JENDL-3.2. Compiled by T.Nakagawa (ndc/jaeri)
(3,2) modified
(3,4) modified
(3,51) modified
(3,55-73) modified
Curves of inelastic scattering cross sections were smoothed
by adding interpolated values at several energy points
01-04 JENDL-3.3 Compiled by K.Shibata (ndc/jaeri)
(1,451) Updated.
(3,1) Mesured data were considered between 110 keV
and 7.5 MeV.
(3,2) Re-calculated.
(3,251) Deleted.
(4,2) Transformation matrix deleted.
(5,16-91) INT=22
01-05 JEFF-3.1 Original data taken from JENDL-3.3 and ENDF/B-VI:
(2,151) Updated
GENERAL INFORMATION
==============================------------------------------------
* Resonance parameters updated up to 200 eV with recent values
extracted from Time-Of-Flight measurements carried out at the
RPI facility [16].
* The Reich-Moore approximation of the R-Matrix theory is used
for this revision
* Above 200 eV, resonance parameters are taken from ENDF/B-VI
* Unresolved Resonance Range and High neutron energies range are
taken from JENDL-3.3
THERMAL CROSS SECTIONS AND RESONANCE INTEGRALS
==============================------------------------------------
* Negative Resonances have been updated to reach average thermal
capture cross section calculated from EXFOR data(21.3+-1.0 b).
* Effective potential scattering length for s-wave channel has
been set to the ENDF/B-VI value of 7.6 fm recomended in Ref[1]
* Thermal cross sections and Resonance Integrals calculated with
the NJOY-99.90 code [18]
| 2200 m/s values | Resonance Integral
| (barns) | (barns)
---------+-----------------+--------------------
Total | 26.8 |
Elastic | 5.5 |
Capture | 21.3 | 694.3
RESOLVED RESONANCE RANGE (RRR): E < 200 EV
==============================------------------------------------
* Resonance Parameters are those reported by M.J. Trbovich in
his PhD Thesis. Original abstract of the PhD Manuscript is
given below:
"Experiments measuring neutron capture and transmission were
performed ath the Rensselaer Polytechnic Institute (RPI) LINAC
Transmission experiments utilized Li-6 glass scintilation
detectors at flight path lengths of 15 and 25 m. Capture
experiments were done using a sixteen section NaI(Tl)
multicplicity type detector at a flight path length of 25 m.
These experiments utilized various thicknesses of metallic and
isotope-enriched liquid samples. The liquid samples were
designed to provide information on the Hf-176 and Hf-178
contributions to the 8 eV doublet without saturation. Data
analysis was done using the R-matrix Bayesian fitting code
SAMMY[17]. The combined capture and transmission data analysis
yielded resonance parameters for all stable hafnium isotopes
from 0.005-200 eV"
* S-wave average parameters:
R' = 7.6 +- 0.7 fm
= 55 +- 9 meV
RESOLVED RESONANCE RANGE (RRR): 200 < E < 700 EV
==============================------------------------------------
Above 200 eV, Resonance Shape Analysis of the RPI data has been
carried out with the resonance parameters available in the
ENDF/B-VI evaluation. Original Comment is:
* Resolved Resonance Parameters from Ref. [1]
* Values of Average Gg are set to 51 meV
* Value for the scattering radius is 7.6 fm [1]
UNRESOLVED RESONANCE RANGE (URR): 700 EV < E < 50 KEV
==============================------------------------------------
Above 700 eV, description of the URR is taken from JENDL-3.3.
Original comment is:
S0, S1, R' and have been adjusted so that the calculated
total and capture cross sections were reproduced well.
D-obs = 55.2 eV
S0 = 2.0e-4
S1 = 1.0e-4
R' = 9.1 fm
= 54.0 meV
HIGH ENERGY RANGE: E > 50 KEV
==============================------------------------------------
Above 50 keV, evaluation of the high energy range is taken from
JENDL-3.3, original comment is:
MF=3 => Neutron cross sections
* MT=1,2,4,51-73,91,102
Total,elastic,inelastic and capture calculated with ecis [2]
and casthy [3]. Deformed optical potential for ecis
calculation was determined so as to reproduce the experimental
starting with the Haouat potential [4]:
V0 = 46.89-0.3*En, Ws = 3.84+0.4*En (En<10), Vso = 6.2 (MeV),
= 7.84 (En>10)
a0 = 0.63, as = 0.52, aso = 0.47 (fm),
r0 = 1.24, rs = 1.24, rso = 1.12 (fm),
beta-2 = 0.276, beta-4 = 0.0.
The deformation parameter beta-2 was determined from the
measured e2 transition probability data [5]. The lowest three
levels belonging to the ground state rotational band were
coupled in the calculation. The spherical optical potential
for casthy calculation is the same as that of JENDL-2:
V0 = 38.0, Ws = 8.0+0.5*sqrt(En), vso = 7.0 (MeV),
a0 = 0.47, as = 0.52 , aso = 0.47 (fm),
r0 = 1.32, rs = 1.32 , rso = 1.32 (fm).
Capture cross section was normalized to the measured data of
beer et al. [6] at 30 keV. Competing processes (n,2n), (n,3n)
(n,p), and (n,alpha) were calculated with gnash [7] and fed to
ecis-casthy calculation. The level fluctuation and
interference effects were considered. Level scheme was taken
from table ofisotopes [8].
no. energy(MeV) spin-parity
g.s. 0.0 0 +
1 0.0883 2 +
2 0.2902 4 +
3 0.5970 6 +
4 0.9980 8 +
5 1.1499 0 +
6 1.2266 2 +
7 1.2477 2 -
8 1.2932 0 +
9 1.3133 3 -
10 1.3413 2 +
11 1.3794 2 +
12 1.4046 4 -
13 1.4458 3 +
14 1.5777 3 +
15 1.6434 1 -
16 1.6723 1 +
17 1.7046 2 +
18 1.7102 3 -
19 1.7221 1 -
20 1.7675 2 -
21 1.7861 3 +
22 1.7937 3 -
23 1.8190 0 -
Continuum levels assumed above 1.8400 MeV.
The level density parameters for Gilbert and Cameron's formula
[9] are the same as those of JENDL-2.
a(1/MeV) c(1/MeV) t(MeV) Ex(MeV) sigma**2
hf-176 22.77 1.74 0.454 4.38 6.09
hf-177 22.61 9.06 0.486 4.38 9.45
NB: modification for JENDL-3.3: For mt=1, measured data [10,11,12]
on natural element were considered in the energy region from
110 keV to 7.5 MeV.
* MT=16,17,103,107: (n,2n), (n,3n), (n,p) and (n,alpha)
Calculated with gnash [7]. The transmission coefficients for
the incident channel were generated with ecis [2], while those
for the exit channels with eliese-3 [13]. The preequilibrium
parameter f2 was adjusted to reproduce the measured (n,2n)
cross section at 14.5 MeV and resulted in f2=5.0.
MF=4 => Angular distributions of secondary neutrons
* MT=2,51-73,91: Calculated with ecis [2] and casthy [3].
* MT=16,17: Isotropic in the laboratory system.
MF=5 => Energy distributions of secondary neutrons
* MT=16,17,91: Calculated with gnash [7].
MF=12 => Photon multiplicities and transition probabilities
* MT=16,17,91,102,103,107
Calculated with gnash [7] and stored under option-1 (photon
production multiplicities). The photon strength functions for
most nuclei were taken from [1], while those for some hafnium
isotopes were determined from capture cross section normaliza-
tion to the experimental data. The photon profile function is
a superposition of the Berman-type giant dipole resonance [14]
and the pygmy resonance whose parameter values were cited from
the neighbouring nucleus Ta [15].
eg1 = 15.23, eg2 = 12.3 , ep = 5.2 (MeV),
gg1 = 4.48, gg2 = 2.43, gp = 2.5 (MeV),
sig-pygmy/sig-gdr = 0.0245.
* MT=51-73: Stored under option-2 (transition probability array)
Data were taken from [8].
MF=14 => Photon angular distributions
* MT=16,17,51-68,91,102,103,107:Isotropic.
MF=15 => Continuous photon energy spectra
* MT=16,17,91,102,103,107: Calculated with gnash [7].
REFERENCES
==============================------------------------------------
1) Mughabghab S.F.: Neutron cross sections, Vol.1, Part B (1984).
2) Raynal J.: IAEA SMR-9/8 (1970).
3) Igarasi S. and Fukahori T.: JAERI 1321 (1991).
4) Haouat G. et al.: Nucl. Sci. Eng., 81, 491 (1982).
5) Raman S. et al.: At. Data Nucl. Data Tables, 36, 1 (1987).
6) Beer H. et al.: Phys. Rev., C30, 464 (1984).
7) Young P.G. and Arthur E.D.: LA-6947 (1977).
8) Lederer C.M. and Shirley V.S.: Table of isotopes 7th edition
(1979).
9) Gilbert A. and Cameron A.G.W.: Can. J. Phys., 43, 1446 (1965).
10) Sherwood G.L. et al.: Nucl. Sci. Eng., 39, 67 (1970).
11) Foster,Jr. D.G. and Glasgow D.W.: Phys. Rev., C3, 576 (1971).
12) Poenitz W.P. and Whalen J.F.: ANL/NDM-80 (1983).
13) Igarasi S.: JAERI-1224 (1972).
14) Berman B.L.: At. Data Nucl. Data Tables, 15, 319 (1975).
15) Igashira M. et al.: Int. Symp. Capture Gamma-ray Specroscopy
and Related Topics - 1984, 523 (1985).
16) Trbovich M.J. et al.: Int. Conf. on Nuclear Data for Science
and Technology, Santa Fe, USA (2004).
17) Larson N.M., Oak Ridge National Laboratory,ORNL/TM-9179/R6
18) MacFarlane R.E., NJOY99 - Code system for producing pointwise
and multigroup neutron and photon cross sections from ENDF/B
Data, RSIC PSR-480 (2000).
CONTENTS
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