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1 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Inelastic scattering on major actinidesR. Capote (IAEA/NDS, Vienna), E. Soukhovitskii (JINER, Minsk),
M. Sin (Univ. Bucharest), and A. Trkov (IAEA/NDS)
2 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Motivation, RPI benchmark 238U DCCOMP + HF + HRTW +”EW” – u238-b44 235U DCCOMP + HF + HRTW – u235-b2New multi-band coupling DCCOMP
OUTLOOK
3 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Motivation
High accuracy requirements were placed on inelastic cross-sections 238U(n,inl) in the whole energy range up to 20 MeV (OECD/NEA WPEC Subgroup 26, NEA, 2008 ).
Changes in PFNS may lead to changes in evaluated inelastic cross sections which are discrepant (cf. INDC(NDS)-0597 (2012))
Physics
Data
Better nuclear structure should be used in reaction calculations for heavy nuclei (beyond rigid-rotor and vibrational models)
Extended multi-band coupling needed with “consistent” coupling
(i.e. able to reproduce OM observables for a given CC scheme)
4 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Danon et al, RPI quasi-integral benchmark U-238
5 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Graphite RPI benchmark (syst. uncert)
6 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
RPI sensitivity to evaluated cross sections
238U, 60 deg
7 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
RPI sensitivity to evaluated cross sections
238U, 153 deg
8 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
60 deg
9 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
60 deg
10 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Evaluated 238U(n,f) vs. IAEA STD cross section
11 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Evaluated 238U(n,f) vs. IAEA STD cross section
raw EXFOR ratio data U8/U5, U5 std
12 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
+ recent relevant modelling advances Dispersive Lane consistent coupled-channel OMPs*:
neutron inelastic scattering to discrete levels; CN-DIR interference effects (as predicted by Moldauer);
neutron inelastic scattering to the continuum; improved fission formalism (descriptive capability)
*J.M. Quesada et al., EPJ Web of Conferences 42 02005 (2013) J.M. Quesada et al., ND2013 conference
Nuclear Data Sheets 108 (2007) 2655
13 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Evaluated 238U(n,f) ib44 (IAEA)
14 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Impact of CN-DIR interference (EW transf.)
Suggested Capote et al, ND2013Confirmed Kawano et al, Varenna 2015
15 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Differences in the maximum: 238U(n,inl)
16 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Differences: 235U(n,inl)
Impact on fast assemblies
Impact on thermal
assemblies
235U ib2 – rr OMP
17 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
0.01 0.1 1
3
4
5
6
RIPL 2408 (5 CC, rigid rotor) new OMP (iter. CC method) new OMP (exact CC method)
Rea
ctio
n cr
oss
sect
ion
(bar
n)
Incident neutron energy (MeV)
Impact of 235U DCC multi-band coupling
18 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
NEW DCCOMPMulti-band coupling
Odd and even-even targets
19 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Lane consistent nucleon dispersive OMP
Coupled: levels of the ground state band/excited bands
))','(,()),','(,( RrVERrV Coul
3/1* '
A
ZZCEE Coul
Coupling models:Rigid rotor, soft rotor, vibro-rotational model
20 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Expanded coupling scheme
Soft (non-axial) rotor (even-even nuclides)Yu.V.Porodzinkij and E. Soukhovitskii, Phys. At. Nuclei 59 (1996) 228-237V.M. Maslov et al., J. Nucl. Sc.Tech. Supl.2 (2002) 148-151
CHALLENGE:Derive a dispersive coupled channel potential (Lane consistent) with multiple-band coupling scheme valid for even-even and odd actinides
D.W.Chan et al, PRC26 (1982) 841; PRC26 (1982) 861 .E.Sheldon. L.E.Beghian, D.W.Chan et al, J.Phys.G:Nucl. Phys. 12, 443 (1986).T. Kawano, N. Fujikawa and Y. Kanda, INDC(JPN)-169 (1993) JENDL-3.2
Vibrational-rotational model (even-even nuclides)
21 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Nuclear shape parameterization
A.Bohr, Mat. Fys. Medd. Dan. Vid. Selsk. 26, No. 14 (1952):Body-fixed frame aligned with principal axes: b2,1=b2,-1=0; b2,2=b2,-2 => , b g
P.O. Lipas and J.P. Davidson, Nucl. Phys. 26, 80-90 (1961): Octupolar vibrations with even projection better describe low-lying negative parity states b3,1=b3,-1=b3,3=b3,-3=0 => =3 ; =0,l m ±2
nonaxial ,
axial, 32
Rigid rotor + dynamical corrections
Small param.
22 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Optical model potential
23 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Even-Even Nucleus
)2,0('' phphphph evenSelection rules:Dn l =0, ±1 : vibrational rule; next spin rules
Intraband transitions:
Quadrupolar-GS:
Octupolar-GS:
evenphph '
2,0,22;0 ' phph
allowednot
phph
3,1
;2,0,33;0 '
=DK m
...
24 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Rigid rotor with soft-rotor (vibr.) corrections
U-238(similar for 232Th)
Yu.V.Porodzinkij and E. Soukhovitkii, Phys. At. Nuclei 59 (1996) 228-237
0.044.9149.6314.2538.6
1166.9(+8.4%)
822.8(+6.0%)
~J(J+1)
rigid
non-axial
octupole
OMP with multiple band couplinggsb
25 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
238U (CC)
26 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Nuclear shape parameterization-odd
= ; DK m
...
Intraband transitions:
Interband-transitions:
evenKK 1' '
),(1
),,,(1
2330'
33132220'
YYoddIf
YYYYevenIf
rule selection particlesingle 10 'Knj
Knj cc
Spin selection rules
27 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
=1,DK pp’=-1<b31>=0
=3,DK pp’=-1<b33>=0isomer
Ground staterigid rotor
=1,DK pp’=-1<b31> =0
235U (not coupled bands)
Kp=1/2+Kp=5/2+ Kp=5/2+Kp=7/2-
28 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
=2,DK pp’=+1< b22> non-axial
=0,DK pp’=-1< b30> axial
=2,DK pp’=-1< b32> non-axial
235U (Coupled bands)Kp=3/2+ Kp=7/2+
Kp=3/2-
Kp=7/2-
Ground staterigid rotor
29 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
239Pu (coupling scheme)
GS, Kp=1/2+ =0,DK pp’=-1< b30> axial
=3,DK pp’=-1< b33> = 0
=2,DK pp’=+1< b22> non-axial
30 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
DCC OMP LSQ fit for all “optical“ observables (n,n);(p,p);(p,n)
RIPL 2408 OMP: rigid rotorR.C., S.Chiba, E.Sh. Soukhovitskii, J.M. Quesada, E. Bauge, Jnst 45 (2008) 333–340
31 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
DCC OMP low-energy observables
RIPL-3: R.C. et al, Nucl. Data Sheets 110 (2009) 3107–3214, online at http://www-nds.iaea.org/RIPL-3 Yu.V. Porodzinskij, E.Sh. Sukhovitskij and V.M. Maslov, INDC(BLR)-012, IAEA, 1997
S.F. Mughabghab, Atlas of Neutron Resonances, 5th edition, Elsevier, Amsterdam, 2006.
Cross Section Evaluation Working Group 1991 Report BNL-NCS-17541 (ENDF201).
32 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
New DCC OMP parameterization
33 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
1E-3 0.01 0.1 1 10 100
4000
8000
12000
16000
20000
24000
0.01 0.1 1 10 100
RC et al, RIPL 2408 (5 CC) multi-band coupling (20 CC)
Foster 1971 Harvey 1988 Peterson 1960 Poenitz 1981 Poenitz 1981
n + 235U
Energy [MeV]Energy [MeV]
Tot
al c
ross
sec
tion
[mb] Peterson 1960
Abfalterer 2001 Grigoriev 1991 Harvey 1988 Poenitz 1981
n + 238U
34 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Total cross section differences
10 1000.00
0.01
0.02
0.03
Abfalterer et al. [12] Rigid Rotor potentials:
RIPL 2408 OMP, Capote et al. (DCC) RIPL 2601 OMP Soukhovitskii et al. (TALYS)
Multi-band coupling (18 CC + 2 IAS)
[ to
t(23
8U
) -
to
t(23
2T
h)]
/
{[ to
t(23
8U
) +
to
t(23
2T
h)]
/2}
Energy [MeV]
35 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
5 10 15 202.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
238U,239Pu(n,CN)
Cro
ss s
ect
ion
(b
arn
s)
Neutron energy (MeV)
U - ANL (new Dietrich eval) EXFOR
n+238U, Multi-band coupling (20 CC) Bauge et al, deformed SMOMP (JLM)
n+239Pu, Multi-band coupling (20 CC)
n+235U, Multi-band coupling (21 CC)
36 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
CONCLUSIONS New DCC OMP with multiple-band coupling derived for nucleon scattering on actinides: 233,235,238U, 239Pu, and 232Th OMP highlights:
Based on dispersive relations and Lane consistent.Least-squares fit of a regional set of OMP parameters from
(n,n),(p,p) & (p,n) IAS.CC couplings based on rigid rotor with dynamical
corrections with derived selection rules for rotational bands built on vibrational (even-even) or single-particle band-heads (odd nuclei).
Energy independent geometry.Ground state deformations close to those predicted by Nix and Moller (FRDM)
37 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
38 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Dispersive relations W<-> V
39 Roberto Capote, IAEA Nuclear Data Section e-mail: [email protected] Web: www-nds.iaea.org
IAEA IAEA HQ, Vienna, Austria, 22-23 June 2015
Couplings in (p,n) IAS reactions
C=1.444Z/A1/3 -1.13 MeV
C~20 MeV for actinidesC
IAS
Ground state