Progress on analysis of nucleon activation cross sections ... · Vlad Avrigeanu EFF/EAF Meeting,...

EFFDOC-977

Progress on analysis of nucleon activation cross sections at medium energies

TW6/TTMN-001/D6

V. Avrigeanu, F.L. Roman, M. AvrigeanuEURATOM-MEC Fusion Association, “Horia Hulubei” National Institute for Physics &

Nuclear Engineering, P.O Box MG-6, 76900 Bucharest, Romaniahttp://tandem.nipne.ro/~vavrig/, http://fp6.cordis.lu/fp6/partners /RCN 49105

R.A. ForrestEURATOM-UKAEA Fusion Association, Culham Science Center, Abingdon OX143DB,

United Kingdom

Vlad Avrigeanu EFF/EAF Meeting, NEA, 22.5.2006 1

http://tandem.nipne.ro/~vavrig/

http://fp6.cordis.lu/fp6/partners


Consistent input parameter set involved for calculation ofall activation cross sections (E<20 MeV) for

n + 174,176,177,178,179,180Hf, 181Ta, 182,183,184,186W (2003-2004)

Improved validation of the model assumptions and formalism

Extension for E< 60 MeV / proton-induced reaction data( 2005 - 2006 )

(e.g., revised calculations for W activation)

Outline[EFFDOC-928 (May 2005), EFFDOC-940 (Nov 2005)] + …

• Nuclear cross sections calculations- Search for appropriate optical potentials [Nucl. Phys. A765 (2006) 1]:

- n + 178Hf, 181Ta, 182,183,184,186W, E<100 MeV [SPRT method]- p + 181Ta (E<60 MeV), 180Hf

- Search for appropriate γ-ray strength functions: (n,γ) reaction analysis- by using suitable neutron DOM parameters (β2 of 178Hf, for all isotopes)

- BSFG level density parameters based on latest resonance data (RIPL-2)- Compilation of available data (E<60 MeV): - n + 181Ta, 174,176,177,178,179,180Hf

- p + 181Ta (for PE trial at E>30 MeV)- Nuclear model calculations (E<60 MeV): TALYS, EMPIRE-II, STAPRE-H.6- Comparison with all activation experimental data

- Isomeric cross sections analysis

• Processing of model calculations results- Cross sections of all individual channels with activation data for

n + 174,176,178,179,180Hf, 181Ta, 182,183,184,186W (revised)



20 40 600.0

0.5

1.0

1.5

2.0

2.5

20 40 600.0

0.5

1.0

1.5

20 40 600.0

0.5

1.0

1.5

20 40 60

1E-4

1E-3

0.01

20 40 601E-6

1E-5

1E-4

1E-3

0.01

20 40 601E-6

1E-5

1E-4

1E-3

Mogharrab+ (1972) Veeser+ (1977) Frehaut+ (1980) Csikai (1982) Takahashi+ (1989)

TALYS-0.64 EMPIRE-2.19

181Ta(n,2n)180Ta


181Ta(n,2n)180gTa

[1+ 8.154h]

Lakshmana Das+ (1978) Ryves+ (1980) Ikeda+ (1988) Hanlin+ (1989) Kasugai+ (1992) Filatenkov+ (1999) Filatenkov+ (2001)

181Ta(n,3n)179Ta

Veeser+ (1977)



Woelfle+ (1988)Han-Lin+ (1989)Kasugai+ (1992)Xiangzhong+ (1992)Begun+ (1999)Filatenkov+ (1999)

181Ta(n,p)181Hf

σ (b

)

[1/2- 42.39d]

Filatenkov+ (2001)Begun+ (2001)

En (MeV)

Begun+ (1999)Filatenkov+(2001)Begun+ (2002)


181Ta(n,α)178gLu

[1+ 28.4m]

Kasugai+ (1992)Begun+ (1999) Filatenkov+(2001)Begun+ (2001) TALYS-0.64 EMPIRE-2.19

181Ta(n,α)178mLu[9- 23.1m]

Questions following the former global analysis (181Ta)[EFFDOC-928 (May 2005), EFFDOC-940 (Nov 2005)]

- Calculated cross sections: most useful at E<60 MeV, not suitable at E<20 MeV- Calculated (n,p) reaction cross sections: large disagreement with experimental data


Flowchart of model calculations[Nucl. Phys. A765, 1 (2006)]

• EMPIRE-II v.2.19 [ECIS95/SCAT2, DEGAS, MSD-TUL/MSC-H, HF]− σt, σR, σCC, σabs - Tl(E) neutron deformed optical potential

- p-, α- spherical optical potentials- EMPIRE-specific level density, Nmax< 40- DEGAS [g=A/13 MeV-1, K=100 MeV3]- PCROSS

• TALYS-0.64 [+ Arjan Koning]

• STAPRE-H.6 (v.2006) [SCAT2, GDH, HF]- p-, α- spherical optical potentials - BSFG, E*<Bn: (a,∆) D0-, Nmax-fit

a(E*), E*>Bn: Junghans/Koning/Chadwick (1998)I/Ir: 0.5(g.s.)-0.75(Bn)-1(15 MeV) [Nucl. Phys. A730, 255 (2004)]

- GDH + gFGM(ε), AK(p,h), fK(p,h,E,F1(l,Ei) [Phys.Rev. C 58,295 (1998)]+ Jπ-conservation [Z.Phys. A 329,177(1988); 335,299(1990)]+ medium energy l-effects [Phys. Rev. C 54, 2538 (1996)]


“Nuclear surface localization of preequilibriumreactions at low energies”

[ M. Avrigeanu, A. Harangozo, V. Avrigeanu, and A.N. Antonov, Phys. Rev. C 54, 2538 (1996) ]

0.0

0.5

1.0

E=60 MeV

Tl

(2l+1)Tl(E) / σR

n + 181Ta

T l (E)

0 5 10 15 20 25 301E-7

1E-5

1E-3

0.1E=60 MeV

Tl

(2l+1)Tl(E) / σR

n + 181Ta

l ( h )

First NN-collision probability: higher E, lower r

Angular momenta involved:


Optical model potentials• Neutrons (n+182,183,184,186W, 181Ta, 178Hf): SPRT analysis

(added in EMPIRE-II output)– P.G. Young+ (1990) [as RIPL-2 in EMPIRE-II] (local)– J.P. Delaroche, as in NEANDC-253”U”, OECD/NEA-DB, 1989 (local)– P.G. Young, NEANDC-222”U”, OECD/NEA-DB, 1986 (global: II-A, II-B)– P.G. Young+ (1990) - modified (local)– RIPL-2/P.G. Young+ (1986) - modified (local)– P.G. Young, OECD/NEA-DB (1986) – II-A: modified (global, E<100)

• Protons (p+181Ta)– R.L. Walter and P.P. Guss, Rad. Effects 92, 1079 (1986) (global)– N. Yamamuro, NDST-1988, Mito, Japan, p.489 (global)– Walter-Guss (1986) - modified (p+181Ta)– Walter-Guss (1986) – p+180Hf

• Alphas– V. Avrigeanu, P.E. Hodgson, M. Avrigeanu, Phys.Rev.C 49,2137(1994) (global)– M.Avrigeanu, W. von Oertzen, V.Avrigeanu, Nucl. Phys. A 754, 246 (2006)


Comparison of calculated and experimental neutron total cross sections for 178Hf, 181Ta, and 182,183,184,186W isotopes

0.01 0.1 1 10

10

20

30

n + 178Hf Young #A (1986), β

2=.24, β

4=-.03, β

6=0

Young #A (1986) - mod. (E>6 MeV)

Tabony+ (1965) Divadeenam+ (1968) Sherwood+ #1 (1970) Sherwood+ #2 (1970) Foster Jr+ (1971) Dilg+ (1972) Green+ #1 (1973) Green+ #2 (1973) Poenitz+ (1983) Smith (2002)

n + Hf

σ (b

)

0.1 1 10 100

5

10

En (MeV)

Foster+ (1971) Poenitz+ (1981) Poenitz+ (1983) natTa Finlay+ (1993)

Young #A (1986), β2=.245, β

4=-.07, β

6=-.025

Young #A (1986) - mod. (E>6 MeV)

n + 181Ta

0.1 1 10 100

4

5

6

7

8

9

Young#A (1986) Young#A (1986)-mod.

Whalen+ (1966) Martin+ (1967) Foster+ (1971) Djumin+ (1977) Guenther+ (1982) Knopf+ (1987) Dietrich+ (2003)

(a)

n + 182W

0.01 0.1 1 10 100

5

10

15

20

2530

Ohkubo+ (1978) #1 Ohkubo+ (1978) #2 Knopf+ (1982) Abfalterer+ (2001): natW Young#A (1986) Young#A (1986)-mod.

(b)

n + 183W

0.1 1 10 1004

5

6

7

8

9

Young#A (1986) Young#A (1986)-mod.

Whalen+ (1966)Martin+ (1967)Foster+ (1971)Djumin+ (1977)Guenther+ (1982)Knopf+ (1982) Dietrich+ (2003)

(c)

n + 184W

En (MeV)0.1 1 10 100

4

5

6

7

8

9

(d)

n + 186W

Whalen+ (1966) Martin+ (1967) Foster+ (1971) Djumin+ (1977) Guenther+ (1982) Knopf+ (1982) Dietrich+ (2003) Young#A (1986) Young#A (1986)-mod.

En (MeV)

[EFFDOC-906]


Comparison of the calculated and measured proton reaction cross sections and (p,n) reaction cross sections for 181Ta and 180Hf

Walter-Guss (1986) - modified (local): WD=10.48-0.250E+14.94η, E<10 MeV9.55-0.157E+14.94η, E>10 MeV

aD= 0.742-0.0115E, E<20 MeV0.512, E>20 MeV

[EFFDOC-906]

10 20 30 40 500.01

0.1

1p + 181Ta

Wilkins-Igo (1963) Thomas+ (1967): (p,n)+(p,pn) Abegg+ (1979) Perey (1963) Menet+ (1971) Koning+ (2002) Walter-Guss (1985) WG-Yamamuro (1988) Walter-Guss mod.

σ R (

b)

Ep (MeV)4 8 12 16

1E-5

1E-4

1E-3

0.01

0.1

181Ta(p,n)181W Hansen+ (1962)/T0121 Chodil+ (1967)/C0693 Thomas+ (1967)/C0695 Zhuravlev+ (1984)/A0271 Perey (1963) Menet+ (1971) Koning+ (2002) Walter-Guss (1985) WG-Yamamuro (1988) Walter-Guss mod.

σ (b

)

Ep (MeV)6 7 8 9 10

0.01

0.1

Norman+(1982): 180TaNorman+(1982): 180gTa Walter-Guss (1985): 180Ta Walter-Guss (1985): 180gTa

180Hf(p,n)180Ta

Ep (MeV)


[EFFDOC-906]

The γ-ray strength functions• Modified energy-dependent Breit-Wigner (EDBW) model28,29: fE1(Eγ) • Comparison of experimental20,30 and the calculated average radiative widths

- Γγ0 (meV) used for normalization of fE1(Eγ) capture data description

Γγ0 180W 182W 183W 184W 186W

RIPL-220 70(15) 62(15) 77(12) 69(17) 61(8) 104Γγ0/D0 (Ref.30) 7.97(37) 45.6(8) 6.00(36) 5.51(25) Γγ0 (from Ref.30 and D0 of Ref.20) 48 55 42 47 Γγ0 for best normalization of fE1(Eγ) 40 47 50 42 35

20A.V. Ignatyuk, at http://161.5.7.5/RIPL-2/resonances/ .28D.G. Gardner and F.S. Dietrich, Report UCRL-82998, LLNL-Livermore, 1979.29M. Avrigeanu, V. Avrigeanu, G. Cata, and M. Ivascu, Rev. Roum. Phys. 32, 837 (1987).30R.L. Macklin, D.M. Drake, and E.D. Arthur, Nucl. Sci. Eng. 89, 98 (1983).


Comparison of calculated and measured neutron capture cross sections of 176,177,178,179,180Hf and 181Ta isotopes

0.01 0.1 10.1

1

Bokhovko+ (1996)

Γγ=60+10 meV [RIPL2]

σ (b

)

176Hf(n,γ)177Hf

Γγ=70 meV

60 meV 50 meV

0.01 0.1 1

0.1

1


Bokhovko+ (1996)

σ (b

)

En (MeV)

177Hf(n,γ)178Hf

Γγ=76 meV

66 meV 56 meV

0.01 0.1 1

0.1

Bokhovko+ (1996)


178Hf(n,γ)179Hf

Γγ=59 meV 54 meV 49 meV

0.01 0.1 1

0.1

1


Bokhovko+ (1996)

En (MeV)

179Hf(n,γ)180Hf

Γγ=71 meV

66 meV 61 meV 51 meV

0.01 0.1 1

0.1


Siddappa+ (1974) Zu-Ying+ (1984) Trofimov #1 (1987) Trofimov #2 (1987) Bokhovko+ (1996) Jinxiang+ (1997)

180Hf(n,γ)181Hf

Γγ=55 meV

50 meV 45 meV 35 meV

0.01 0.1 1

0.1

1 Γγ=57+3 meV [RIPL2]

Γγ=60 meV

57 meV 54 meV

Siddappa+ (1974) Poenitz (1975) Lindner+ (1976) Kononov+ (1977) Yamamuro+ (1978)

En (MeV)

181Ta(n,γ)182Ta

Allen+ (1981) Voignier+ (1986) Haishan+ (1986) Haishan+ (1988) Bokhovko+ (1996)

[EFFDOC-906]

Comparison of measured and calculated 181Ta(p,xn) reaction cross sections

• PE threshold in CP-induced reactions

e.g., H.C.Chiang+, Nucl.Phys. A340,466(1980):

σPE ~ (1 - VC / E) [ beff~ b(1 - VC / E)1/2 ]

10 20 30 40 50 60 700.0

0.5

1.0

1.5

2n

1n

No PE Shubin+ (1994, MEDNL-2) TALYS-0.64 [(p,3n)179mW] STAPRE-H.6 [(p,3n)179mW]

4n

3n

Thomas+ (1967): (p,n)Thomas+ (1967): (p,2n)Birattari+ (1971): (p,3n) ?Birattari+ (1971): (p,4n)Zaytseva+ (1994)Michel+ (2002)

181Ta(p,xn)

σ (b

)

En (MeV)


Comparison of measured and calculated 181Ta(n,xn) reaction cross sections

No PEGDH (STAPRE-H.6)

10 20 30 40 50 600

1

2

n

σ (b

)

σR

6n5n

3n

2n

4n

181Ta(n,xn)

En (MeV)Vlad Avrigeanu EFF/EAF Meeting, NEA, 22.5.2006 13

Comparison with experiment


Comparison of the measured and calculated reaction cross sections for the target nucleus 181Ta

Calculations with EMPIRE-II and TALYS, and default global parameters (except local OMPs), and STAPRE-H with local parameter set.

20 40 600.0

0.5

1.0

1.5

2.0

2.5

20 40 600.0

0.5

1.0

1.5

20 40 600.0

0.5

1.0

1.5

20 40 60

1E-4

1E-3

0.01

20 40 601E-6

1E-5

1E-4

1E-3

0.01

20 40 601E-6

1E-5

1E-4

1E-3

Mogharrab+ (1972) Veeser+ (1977) Frehaut+ (1980) Csikai (1982) Takahashi+ (1989)

TALYS-0.64 EMPIRE-2.19 STAPRE-H.6

181Ta(n,2n)180Ta


181Ta(n,2n)180gTa

[1+ 8.154h] Lakshmana Das+ (1978) Ryves+ (1980) Ikeda+ (1988) Hanlin+ (1989) Kasugai+ (1992) Filatenkov+ (1999) Filatenkov+ (2001)

181Ta(n,3n)179Ta

Veeser+ (1977)



Woelfle+ (1988)Han-Lin+ (1989)Kasugai+ (1992)Xiangzhong+ (1992)Begun+ (1999)Filatenkov+ (1999)

181Ta(n,p)181Hf

σ (b

)

[1/2- 42.39d]

Filatenkov+ (2001)Begun+ (2001)

En (MeV)

Begun+ (1999)Filatenkov+(2001)Begun+ (2002)


181Ta(n,α)178gLu

[1+ 28.4m]

Kasugai+ (1992)Begun+ (1999) Filatenkov+(2001)Begun+ (2001) TALYS-0.64 EMPIRE-2.19 STAPRE-H.6

181Ta(n,α)178mLu[9- 23.1m]

Comparison of measured and calculated (n,α) reaction cross sections for the target nucleus 181Ta

10 15 20 10 15 2010 15 200.000

0.001

0.002

0 5 10 15 20

0.2

0.4

0.6

0.81

E. Browne, Nucl. Data Sheets 72, 221 (1994):

A 5-min activity was observed only in the 181Ta(n,α) reactionand assigned to 178Lu. A measurement of the cross-section ratio σ(n,α) (5 min)/ σ(n,α) (g.s.) as a function of E(n) indicates spins of 8+ or 9- for 178Lu (5 min). The excitation energy of this isomer is unknown.

En (MeV)

En (MeV)

Begun+ (1999) Filatenkov+ (2001) Begun+ (2002)

STAPRE-H.6

181Ta(n,α)178gLu

En (MeV)

[1+ 28.4 min]

Kasugai+ (1992) Begun+ (1999) Filatenkov+ (2001) Begun+ (2001)

STAPRE-H.6

181Ta(n,α)178mLu

En (MeV)

[9- 23.1 min] Majeddin+ (1997)

STAPRE-H.6

181Ta(n,α)178g+mLu

σ (b

)

181Ta(n,α)178mLu [9- 23.1 min]

σm/σ

g(1+ )

Agrawal+ (1980) [(8+,9-) 5 min] Filatenkov+ (2001) [9- 23.1 min] σm(7-)/σg(1

+)

σm(9-)/σg(1+)

181Ta(n,α)178mLu [7- 5 min]



0 5 10 15 20

0.2

0.4

0.6

0.81

E. Browne, Nucl. Data Sheets 72, 221 (1994):A 5-min activity was observed only in the 181Ta(n,α) reactionand assigned to 178Lu. A measurement of the cross-section ratio σ(n,α) (5 min)/ σ(n,α) (g.s.) as a function of E(n) indicates spins of 8+ or 9- for 178Lu (5 min). The excitation energy of this isomer is unknown.

181Ta(n,α)178mLu [9- 23.1 min]

σm/σ

g(1+ )

Agrawal+ (1980) [(8+,9-) 5 min] Filatenkov+ (2001) [9- 23.1 min] σm(7-)/σg(1

+)

σm(9-)/σg(1+)

181Ta(n,α)178mLu [7- 5 min]

ENSDF:

178Lu isomeric states

Our assumption:

136 keV, 7- : 5 min


Calculated 181Ta(n,αx) reaction cross section[to be completed by contribution of (n,xα) reactions]

GDH (STAPRE-H.6)

10 20 30 40 50 600.000

0.005

0.010

En (MeV)

181Ta(n,αx)

σ (b

)


Isotopic effects in the (n,p) reaction cross section on Hf and W isotopes[ Isotopic effect on W isotopes: R. Caplar et al., Z. Phys. A 313, 227 (1983) ]

0.000

0.005

0.010

0.015

10 15 20

0.000

0.005

0.010

0.015

0.020

[3- 114.43 d]Qaim+ (1975) Grallert+ (1993)LNZ (1997)Filatenkov+ (2002)

STAPRE-H.6 EMPIRE-II: g=A/14 TALYS: gi=Ni/14

(a)

182W(n,p)182TaQaim+ (1975) Grallert+ (1993)Filatenkov+ (2002)


(b)

183W(n,p)183TaQaim+ (1975)Ikeda+ (1988)Kasugai+ (1992)Grallert+ (1993)LNZ (1997)Filatenkov+ (1999)Filatenkov+ (2002)


(c)

184W(n,p)184Ta

10 15 20

Coleman+ (1959)Poularikas+ (1960) Mukherjee+ (1963) Qaim+ (1975)Kasugai+ (1992)Sutoh+ (1994)Murahira+ (1995)Filatenkov+ (1999)Filatenkov+ (2002)


(d)

186W(n,p)186Ta

10 15 200.000

0.005

0.010

0.015

Meason+ (1966) Kirov+ (1993) Murahira+ (1995)

TALYS: gi=Ni/14 STAPRE-H.6 EMPIRE-II: g=A/14

178Hf(n,p)178mLu[9- 23.1M]

Meason+ (1966) Kirov+ (1993)

TALYS: gi=Ni/14 STAPRE-H.6 EMPIRE-II: g=A/14

178Hf(n,p)178gLu

[1+ 28.4M] Konno+ (1990) Konno+ (1993) TALYS TALYS: gi=Ni/14 STAPRE-H.6 EMPIRE-II: g=A/14

179Hf(n,p)179Lu

[7/2+ 4.59H]

10 15 20En (MeV)

En (MeV)

σ (

b)

STAPRE-H.6 TALYS: gi=Ni/14 EMPIRE-II: g=A/14 EMPIRE-II

Kasugai+ (1994) Murahira+ (1995)

180Hf(n,p)180Lu[5+ 5.7MIN]

STAPRE-H.6 EMPIRE-II TALYS: gi=Ni/14

Woelfle+ (1988) Han-Lin+ (1989) Kasugai+ (1992) Xiangzhong+ (1992) Begun+ (1999) Filatenkov+(1999)

181Ta(n,p)181Hf

[1/2- 42.39d]

Filatenkov+(2001)Begun+(2001)

0.16 0.18 0.20

-3

0

6

9

Sp

Sn

Hf Ta WQ

(n,p

) (MeV

)

(N-Z)/A

Possible reason for the actual modeloverestimation of 181Ta(n.p)181Hf data:• actual data: 181Ta(n.p)181gHf • unknown (long-life) isomer of 181Hf


Conclusions• Achievements

- Unitary description of all nucleon activation experimental data (E<60 MeV) by using a localparameter set in STAPRE-H code

- Good results of blind calculations and global parameters within EMPIRE-II and TALYS codes

• Problems- Major uncertainty of calculated isomeric ratios: level & decay schemes

• 5-min activity observed only in the 181Ta(n,α)178Lu reaction: assumed to belong to the level 136 keV 7- of 178Lu

• Possible reason for the actual model overestimation of 181Ta(n.p)181Hf data:the existence of an unknown (long-life) isomer of 181Hf

- (n,p)-, (n,α)-reaction excitation functions at En>15 MeV

• Completion - Extension: n+181Ta, n+174,176,177,178,179,180Hf, E< 60 MeV

p+181Ta, E<60 MeV

• Needs- (n,xn)-, (p,xn )-reaction data at E<60 MeV

- (n,p)-, (n,α )-reaction data at En>15 MeV- (n,d) reaction data (emission spectra, e.g., LLNL-Livermore)

• Work in progress: n + 55Mn, 63,65Cu, E<60 MeV (2006)

Progress on analysis of nucleon activation cross sections ... · Vlad Avrigeanu EFF/EAF Meeting,...

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Transcript of Progress on analysis of nucleon activation cross sections ... · Vlad Avrigeanu EFF/EAF Meeting,...