IMPULSE NUCLEOSYNTHESIS Yu.S. Lutostansky, V.I. Lyashuk, and I.V. Panov National Research Center "Kurchatov Institute" Institute of Nuclear Research RAS Institute of Theoretical and Experimental Physics ITEP

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IMPULSE NUCLEOSYNTHESIS Yu.S. Lutostansky,
V.I. Lyashuk, and I.V. Panov National Research
Center "Kurchatov Institute"Institute of
Nuclear Research RAS Institute of Theoretical
and Experimental PhysicsITEP 10.09.2013
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PROCESSES OF NUCLEOSYNTESIS.
Superheavy nuclei
ß-decay
fission
s-process track
r-process track
ß-decay
The tracks of elements synthesis in s (slow)-
and r (rapid)- processes.
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NUCLEOSYNTHESIS OF THE HEAVY NUCLEI
Dynamic r-process
NUCLEOSYNTHESIS OF THE HEAVY NUCLEI in s
(slow) and r (rapid)- processes ? nuclei
withT1/2 ? 1 y. ? T1/2 lt 1 y.
 - predictions. Dynamic r-process
track.
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r process equations for the concentration
calculations.Dynamic model ?n?/ ?n(A, Z)? ? n?/
?n (A, Z, t) n(A, Z) ? n(A, Z, t)

• Concentrations n(A,Z, t) are changing in time
  (may be more than 4000 equations)
•  
• dn(A, Z, t)/dt ??(A, Z).n(A, Z, t)
  ?n?(A, Z, t).n(A, Z, t)
• ??n(A1, Z, t).n(A1, Z, t) ?n?(A1, Z,
  t).n(A1, Z, t) ??n(A, Z).n(A, Z, t)
• ??(A, Z1).n(A, Z1, t) P?(A, Z1)
  ??(A1,Z1).n(A1,Z1,t) P1n(A1,Z1)
• ??(A2,Z1).n(A2, Z1, t)P2n(A2,Z1)
  ??(A3,Z1)n(A3, Z1, t) P3n(A3,Z1)
• Ff (A, Z) ??(A, Z, t)
• ?n?(t) and ??n(t) rates of (n,?) and
  (?,n) reactions all fluxes and spectra are time
  depended
• ??ln(2/T1/2) ?-decay rate,
• P? - probability of (A, Z) nuclide
  creation after ?-decay of (A,Z-1) nuclide.
  Branching coefficients of isobaric chains - P1n,
  P2n, ?3n corresponds to probabilities of one-,
  two- and three- neutrons emission in
• ?- decay of the neutron-rich nuclei.
• Ff (A, Z) describes fission processes
  spontaneous and beta-delayed fission.
• ??(A, Z) - neutrino capturing processes.

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MODEL DESCRIPTION OF Sß(E) 2. T1/2 calculations
1988.
Time of new nuclei synthesis
ß-decay time Fermi-function
The dependence of r-process duration time on mass
A-value under different external conditions
curve 1) constant nn1026 cm-3, T1.5 109K 2)
the same nn, T1.109K 3) dynamical
calc. with ?02.105 g/cm5, T1.109K ?(t) ?0 .
??p (-t/?H), ?(t) ?0 . ???(-t/3?H).
Yu.S. Lutostansky, and I. V. Panov. Astron.
Letters. 14, no 2 (1988) 168.
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DYNAMIC MODEL OF NUCLEOSYNTHESIS
Yelds of Nuclei, calculated in static (curve 2)
and dynamic pulse r processes (curves 3 and 4).
Numbers denote 1- exp abundance data.
Curves 2 and 3 - Calculations with different
parameters. Curve 2 nn1024 ?m-3, ?9109K,
??? Curve 3 ?0 2?105 g??m-3, ?92x109K,
??1 s. Curve 4 (doted line) calculations
with solar abundance initial nuclei concentration
of s elements.
Lyutostansky Yu.S., Malevanny S.V., Panov I.V.,
Chechetkin V.M. Canada 1987
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Yields (concentrations in relative units) for
Par and Barbel experiments
Yields of transuranium nuclei measured in the
thermonuclear explosions Par and Barbel
(LANL data). Red line
approximation Y exp(1.442A 354.56)
??? ?? 7?1024 ?/??2
Par ?n 7?1024 n/cm2
Barbel
??????
Odd-Even inversion effect
?.?. ????????????, ?.?. ?????, ?.?. ?????.
???????? ?? ???? ???. ???. 1990, ?. 54, ???.
2137 ???????? ???? 25-90, ?. 1990.
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Prompt process in the explosive nucleosynthesis
Multiple neutron capturing process on Uranium
material (U target) , t lt 10-6 s.
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r(rapid) process in the explosive
nucleosynthesis


The initial concentration changed because of
ß-delayed fission and neutron emission during
cooling processes (return to the value of
ß-stability).
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Factor of the concentration losing in
Prompt-process
Np ß-delayed fission probabilities
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NUCLEOSINTHESIS AFTER NEUTRON PULSE 1
????? ??????????? ????????? ? ??????? (r-???????)
????????????? (??????? ?????) ? ???? ? T1/2 ?
1 ? ? ???? ? T1/2 lt 1 ?  - ??????????????
?????????-?????????? ????
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NUCLEOSINTHESIS AFTER NEUTRON PULSE 2