Introduction Introduction Rapid nucleosynthesis – models and sites Rapid nucleosynthesis – models and sites R-process under high neutron environment R-process.

• IntroductionIntroduction• Rapid nucleosynthesis – models and sitesRapid nucleosynthesis – models and sites• R-process under high neutron environmentR-process under high neutron environment• Fission in the r-process Fission in the r-process • (n,f)- and (n,f)- and -delayed fission-delayed fission• fission cyclingfission cycling• sf sf – predictions – predictions • Theoretical Abundance of heavy nuclei Theoretical Abundance of heavy nuclei • Superheavy nuclei and cosmochronometersSuperheavy nuclei and cosmochronometers• ConclusionConclusion

Models for spontaneous fission of heavy nuclei and Models for spontaneous fission of heavy nuclei and nucleosynthesis of cosmo-chronometers in the r-process.nucleosynthesis of cosmo-chronometers in the r-process.

Panov IgorPanov Igor((ITEPITEP, , NGU NGU))

s-, r- processes

SHE

nucleosynthesis beyond Fe-peak – nucleosynthesis beyond Fe-peak – r-r-process andprocess and s-processs-process

4

r-process andr-process and s-process pathss-process paths

supernovae

NSMNSM

J.TruranJ.Truran

windswinds

Nuclear data for the r-process: ~6000 nuclei are involved900 nuclei hasT12 > 1 hour

нуклеосинтез в реакциях с нейтронами (нуклеосинтез в реакциях с нейтронами (s-s-процесспроцесс))::

105106 107 129

Pd Ag Cd n << nn<1012

Z=46

Z=47

Z=48

108 109 110

109 110

110 111 112109

108107

108108

111

-

нуклеосинтез в реакциях с нейтронами (нуклеосинтез в реакциях с нейтронами (r-r-process)process)::

126127 128 129

Ag Cd In n (s-процесс: n << nn>1022 nn<1012

Z=47

Z=48

Z=49

130

Waiting point

129 130 131

130 131

131 132 133

SnII SnII ,, ~ ~ 0 exp(-t/exp(-t/hyd),), hyd < < 10ms10ms

Merging of close binaries:Merging of close binaries: NSNS, NSBHNSNS, NSBH

high n/seeds > 150, Thigh n/seeds > 150, T99< 1, Y< 1, Yee < 0.1 < 0.1

Neutrino-inducedNeutrino-induced rr--process process 44He(He(,,’ n)’ n)33HeHe

Explosions on the NS surfaceExplosions on the NS surface

Hot Hot -wind, high entropy wind -wind, high entropy wind

– – thermonuclear Sne, jetsthermonuclear Sne, jets ? ?

Other objects and processes?Other objects and processes?

2. Main conditions for the r2. Main conditions for the r--processprocess:: ((seedsseeds); ); free neutrons; n/seeds; freezout free neutrons; n/seeds; freezout

Wasserburg, G., Busso, M., & Gallino, R. 1996, ApJ, L109

2 2 objects /scenario: Main r-process - Weak r-objects /scenario: Main r-process - Weak r-process process

weak r-process SNIa- Truran & Cowan He-flash 1983- Blinnikov, Panov, Ptytsin, Chechetkin 1995

SNIIneutrino-induced r-process-Nadyozhin, Panov, Blinnikov A&A, 335, 1998

NSM-model, main r-process?Freiburghaus et al., AJL 525, 1999 NS+BHJanka, Wanajo, 20011

Blinnikov, S. I., et al. Pazh, 10, (1984) 422Lattimer et al., AJ 213, 225 (1977)

fission

3. R-process under high neutron density environment – in NSM

Observed Nr

fissionfission

decaydecay

PPkn (k=0,1,2,3)

Network calculations of the r-processNetwork calculations of the r-process

(n,) (n)

10

Nuclear data for the r-process (up to 6000 nuclei )

• beta-decay,

•Cross-sections and reaction rates (n,g), (n,f), ..

• beta-delayed processes Pin, Pdf

• spontaneous fission, sf

•Mass distribution of fission products•Alpha-decay, •Nuclear masses and fission barriersData base of common usage

JINA - Joint Institute of Nuclear AstrophysicsJINA - Joint Institute of Nuclear Astrophysics

• Seeger, Fowler, et al. (1965) ; Ohnishi (1977) • Thielemann, Metzinger, Klapdor, Zt.Phys., A309 (1983) 301. Pdf=100%• Goriely et al. Astron. Astrophys. 346, 798–804 (1999) s.f. (Swiatecky)• Panov et al., Nucl. Phys. A, 718 (2003) 647. (n,fission) vs Pdf

• I.Korneev et al. NIC-2006; Astronomy Letters, 66 (2008) 131 Yff(Z,A)• Kelic, et al., Phys. Lett. B. 616 (2005) 48 Yff(Z,A)• I.V. Panov, E. Kolbe, F.-K. Thielemann, T. Rauscher, B. Pfeiffer, K.-L. Kratz.

NP A 747 (2005) 633 (n,fission) (n,) Pdf

• G.Martinec-Pinedo et al, Progress in Particle and Nuclear Physics, 59 (2007) 199. (n,fission) vs Pdf

• Y.-Z. Qian, Astron. J. 569 (2002), p. L103. induced fission

• Kolbe, Langanke, Fuller. Phys Rev Lett. 2004 induced fission • I. Petermann et. al. NIC-2008; G.Martinec-Pinedo et al, Progr. in Particle

and Nucl. Phys., 59 (2007) 199-205: (n,fission), Pdf , s.f., induced f..• Panov et al. AA 2010Panov et al. AA 2010 (n,fission) and (n,) • Petermann Martinec-Pinedo Langanke Panov Thielemann SHE AA2012• Panov, I.Korneev, Yu. Lutostansky, F.-K. Thielemann. Yad.Fiz. 2013. Pdi

4. fission in the r-process and rates fission in the r-process and rates calculationscalculations

nf , nf , nn andand rates rates comparison comparison

for U (left) and Cm (right)for U (left) and Cm (right)nn, nf, , nf, n – Hauser-Feshbach predictionsn – Hauser-Feshbach predictions

, , dfdf, - QRPA, - QRPA

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6. Fission cycling during r-process for NSM conditions 6. Fission cycling during r-process for NSM conditions (t-duration time of the r-process; t=0 - initial composition)(t-duration time of the r-process; t=0 - initial composition)

Neutron star mergers modelling: Rosswog et al. 1999R-process: Panov I., Thielemann F.-K. AL, 30 (2004) 711

6. Fission cycling – fission fragments are involved in the r-process as new seeds

I.Petermann, A.Arcones, A.Keli´c, K.Langanke, G.Martínez-Pinedo, W.Schmidt, K-H.Hix, I. Panov, T. Rauscher, F.-K. Thielemann, N.Zinner, NIC-2008;

R=∫i(t) / ∑i ∫ i(t)dt

: Bf < Sn; : nuclei with Bf ≥ Sn; inclined crosses: nuclei with neutron binding energy predicted by the ETFSI Sn ~ 2 MeV; and dots: nuclei in which 2 > Sn > 0. 20

7. Spontaneous fission 7. Spontaneous fission ratesrates

• LgLg((sf sf )) ~ B~ Bff (Frankel&Metropolis,1947) : (Frankel&Metropolis,1947) :

LgLg((sf sf ) =) = 33,3-7,77B33,3-7,77Bff(exp) (exp) (1) (1)

LgLg((sf sf )) =50,127-10,145B=50,127-10,145Bff(etfsi) (etfsi) (2) (2)

• LgLg((sf sf ) = ) = --11461146,,4 + 754 + 75,,33ZZ22//A A –– 11,,638(638(ZZ22//AA))22

+ 0+ 0,,012(012(ZZ22//AA))33 --(7(7,,24 24 --00,,095095ZZ22//AA))BBf f (3)(3)

Zagrebaev, Karpov 2012 (Zagrebaev, Karpov 2012 (Swiatecki, 1957)Swiatecki, 1957)

• Macro-micro model, Smolanchuk et al. Macro-micro model, Smolanchuk et al. 19971997 (4) (4)

Bf ETFSI- Mamdouh et al., NP 2001

R-process path and abundances YA(Z,N) when duration r ~ 10s

nn < 1022 cm-3, n < Squares – most abundant nucleiWhite dots: 10% < Pdf < 90%

25

nn < 1012, n <<

JINR => Zagrebaev et al. Phys. Rev. C 84, 044617 (2011)

Amax(progenitors) ≈280

A(progenitors) ~ < 260

Final abundances YFinal abundances YA , R ~ 0.4 – 4 109 years

Final abundance YA when s.f. rates ~

f(Bf)

Final YA when s.f.rates - macro-micro model

30

ConclusionsConclusions• It was shown that s.f. model applied to the r-It was shown that s.f. model applied to the r-

process nucleosynthesis strongly influe in first process nucleosynthesis strongly influe in first turn on yields of nuclei-cosmochronometersturn on yields of nuclei-cosmochronometers

• Among tested models of spontaneous fission Among tested models of spontaneous fission phenomenological model based on Swiatecki phenomenological model based on Swiatecki model and on macro-micro model predictions model and on macro-micro model predictions gave the better results in calculation of yields gave the better results in calculation of yields of nuclei–cosmochronometersof nuclei–cosmochronometers

• Additionally to 232/235, 235/238 pairs of Additionally to 232/235, 235/238 pairs of nuclei-cosmochronometers, pairs 232/244 or nuclei-cosmochronometers, pairs 232/244 or 238/244 can be considered238/244 can be considered

• The detailed investigation of decay chain is The detailed investigation of decay chain is neededneeded

Thank youThank you !!

• Participants for attentionParticipants for attention

• Blinnikov, Dolgov, Korneev, Blinnikov, Dolgov, Korneev, Thielemann Thielemann for for collaborationcollaboration

Fission cycling – fission fragments are involved in the r-process as new seeds

Bf TF Myers, Swiatecky 1999

Map of nuclei and field of Map of nuclei and field of ratesrates

o - “солнечная” распространенность элементов синим цветом – расчет для сценария слияния нейтронных звезд в двойной системе ( Панов, Корнеев и Тилеманн. Письма в АЖ, т.34, 2008;)

ModelModel, , SSSS and and metal-poor halo star CS 22892-052