1. The r-process element abundance with a realistic fission fragment mass distribution
S. Chiba, H. Koura, T. Maruyama (JAEA)
M. Ohta, S. Tatsuda (Konan University)
T. Wada (Kansai University)
T. Tachibana (Waseda University)
K. Sumiyoshi (Numazu CT)
K. Otsuki (MSU)
T. Kajino (NAO)

2. Fission (cycling) in r-process nucleosynthesis
Discovery of Ｔｈ and Ｕ in metal poor stars
For realistic calculation of r-process nucleosynthesis
Is there a termination point?　Where is that?
Possibility of SHE generation and discovery of its relics in meteorites
Impacts on universality (56≦Z≦75)
Impacts on nucleo-cosmochronometers
Th/Eu, U/Th, Th/Os,....

3. S=250
Supply to medium-weight region by fission, which is less sensitive to the physical conditions of r-process sites
Continuous flow from the bottom

4. Nuclear data for r-process network calculation including fission
Nuclear mass and β-decay rates
KTUY05 (Prog. Theor. Phys. 305（2005 ）113)+ GT2 (this work)
β-delayed fission rates：new calculation by Gross Theory-2 (GT-2)：mass and Bf from KTUY05 vs. MS96　(this work)
Difference due to fission
with or without fission
symmetric fission⇔realistic distribution by Konan group (this work)

5. Regions where fissions take place in terms of KTUY05

6. Calculation of FFMD (Fission Fragment Mass Distribution)
Presented by M. Ohta in ND07 and INPC07, S. Tatsuda P-30 (this symposium)
Static effect: PES by 2-center shell model
collective coordinates：mass asymmetry, distance between fragments, deformation of fragments
yields asymmetryα
Dynamic effets：based on multi-dimensional Langevin calculation for U, Sg and Fm
ratio of symmetric and asymmetric fission： determined by considering calculated and experimental results for Fm isotopes, especially for 264Fm
width of FFMD：determined by considering Langevin calculation
FFMD is expressed by 3 Gaussians

7. FFMD　248Cm, 236U

8. FFMD　236U, 274U

9. β-decay rate by Gross Theory

10. β-delayed fission probability Pf
Gross Theory of β-decay
(TT,Yamada)
β-delayed fission or neutron probability
Sβ (E): β-strength function
λ: decay const. of β-decay
f (-E): Fermi function
KTUY mass formula
Qβ : β-decay Q-value
Sn: neutron sep. energy
Bf: fission barrier height
δW:shell energy
Decay width Γn and Γf
Phenom. formula
(Kawano, SC,HK)
Level density formula (Gilbert-Cameron type)
Tachibana 10

11. Dynamical network calculation Terasawa et al., ApJ 562, 470(2001)
Reaction rates　
Thielamann , Caughlan-Fowler, Maleney-Fowler, Fowler-Hoyle, Rauscher, Mohr, Wagoner, Kajino-Boyd, Orito-Kajino-Mathews, Kajino-Fukugita,Ohsaki, NACRE96
Nuclear mass
Hilf-Groote-Takahashi (modified) KTUY05 (Prog. Theor. Phys. 305（2005 ）113)
β-decay rates
Klapdor GT-2 with KTUY05 mass, including 1n emission(2007)
ν-induced spallation rate (A(ν,e- xn)A') (x=0, 8)
Langanke (5 ≦ Z ≦100) with dumping
no fission mode ⇒β-delayed fission, spontanious fission(KTUY05)
α-decay (KTUY05 mass)
Data on expanding matter of SNeII : numerically read ⇒ exponential model

12. Exponential model for expanding nuclear matter
c.f. General-relativistic hydro-dynamical simulation by Terasawa (ApJ 562, 470(2001))（dots）
lower 2 lines : T9
upper 2 lines : density
Exponential model
Ye=Yp=0.427

13. Entropy-dependence of r-process abundance

14. Realisrtic FFMD（left） vs. symmetric FFMD（right）

15. β-delayed fission probabilities (with Bf of KTUY05)

16. β-delayed fission probabilities (with Bf of Myers-Swiatecki96)

17. β-delayed fission probabilities (with Bf of KTUY - 3MeV)

18. Impact of FFMD on abundance : realistic (left) vs. symmetric(right)

19. (KTUY-3MeV（left）、MS96（right）)

20. Isotope (or element) production rates

21. Concluding remarks
We are on a way to construct nuclear data relevant to r-process network calculation
So far, we have prepared
FFMD (Fission Fragment Mass Distribution)
Nuclear mass : KTUY05
β-decay rates : Gross Theory
β-delayed fission rates
β-delayed neutron emission rates
We have carried out r-process dynamical network calculations with β-delayed fission and found
Strong model dependence onβ-df rates due to difference in Bf
If β-ｄｆ is significant, FFMD has a strong impact on abundance
If β-df is significant, universality is influenced
The model uncertainty in the fission barrier height is still large (around 3 MeV) to make quantitative conclusions on the effect of fission in the r-process abundance
Ultimately, we need (n,f) reaction rates : the statistical model code is ready; we need to refine Bf

22. β遅延中性子放出、β遅延核分裂 TS-1 TS-2 Tn Tγ Sn Bfi Bfo PES
deformation (elongation)

23. , R : Radius of the spherical compound nucleus
Calculation of PES
　Liquid drop model + 2-center shell model
3-dimensional parameter space
　- distance between fragments
　- deformation of fragments
　- mass asymmetry A1 A2
, R : Radius of the spherical compound nucleus

24. β-df region in terms of KTUY05
208Pb
β-stable nuclei
132Sn
・β-df nuclei by
KTUY05 model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line
238U
208Pb
132Sn
β-stable nuclei
・β-df nuclei by
KUTY mass model
n-drip line

25. Z分布(S=250)

26. Z分布(S=400)