neutron induced resonance reactions
DESCRIPTION
Frank Gunsing CEA/Saclay DSM/IRFU/SPhN F-91911 Gif-sur-Yvette, France [email protected]. Neutron induced resonance reactions. Re action: • X + a Y + b • X(a,b)Y • X(a,b) Examples of equivalent notations : Reaction cross section , expressed in barns, 1 b = 10 –28 m 2 - PowerPoint PPT PresentationTRANSCRIPT
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 1
I R F U
Neutron induced resonance reactions
Frank Gunsing
CEA/Saclay
DSM/IRFU/SPhN
F-91911 Gif-sur-Yvette, France
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 2
I R F U
Neutron-nucleus reactions
Reaction: • X + a Y + b• X(a,b)Y• X(a,b)
Examples of equivalent notations:
Reaction cross section , expressed in barns, 1 b = 10–28 m2
Neutron induced nuclear reactions:• elastic scattering (n,n)• inelastic scattering (n,n’)• capture (n,)• fission (n,f)• particle emission (n,), (n,p), (n,xn)
Total cross section tot: sum of all reactions
238U + n 239U*238U + n 239U + 238U(n,)
10B + 1n 7Li + 4He10B + n 7Li + 10B(n,)
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 3
I R F U
Neutron-nucleus reactions
Reaction: • X + a Y + b• X(a,b)Y
Cross section: function of the kinetic energy of the particle a
Differential cross section:function of the kinetic energy of the particle aand function of the kinetic energy or the angleof the particle b
Double differential cross section: function of the kinetic energy of the particle aand function of the kinetic energy and the angleof the particle b
aa
XX YY bb
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 4
I R F U Cross sections n et f
neutron energy (eV)
cro
ss s
ecti
on
(b
arn
)
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 5
I R F U
10-3
10-2
10-1
100
101
102
0 10000 20000 30000 40000 50000
En (eV)
tota
l cro
ss s
ecti
on
(b
arn
)
56Fe + n
Interference of potential and n
transmissionT = exp(–n.T)
0<T<1
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 6
I R F U The nucleus as a quantum system
neutrons protons –V0
0
level scheme representation:excited states of a nucleus(shell model and other states)
ground state
1st excited state
2nd excited state
3rd excited state
AXe
xcita
tion
en
erg
y
nuclear state
shell model representation: configuration of nucleons in their potential
po
ten
tial d
ep
th
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 7
I R F U The nucleus as a quantum system
neutrons protons
po
ten
tial d
ep
th
–V0
0
AX
nuclear state
level scheme representation:excited states of a nucleus(shell model and other states)
shell model representation: configuration of nucleons in their potential
ground state
1st excited state
2nd excited state
3rd excited state
exc
itatio
n e
ne
rgy
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 8
I R F U The nucleus as a quantum system
neutrons protons
po
ten
tial d
ep
th
–V0
0
AX
nuclear state
level scheme representation:excited states of a nucleus(shell model and other states)
shell model representation: configuration of nucleons in their potential
ground state
1st excited state
2nd excited state
3rd excited state
exc
itatio
n e
ne
rgy
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008 9
I R F U The nucleus as a quantum system
neutrons protons –V0
0
AX
nuclear state
level scheme representation:excited states of a nucleus(shell model and other states)
shell model representation: configuration of nucleons in their potential
ground state
1st excited state
2nd excited state
3rd excited state
po
ten
tial d
ep
th
exc
itatio
n e
ne
rgy
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
Decay of a nuclear state
state with a life time :
definition (Heisenberg):
Fourier transform gives energy profile:
eigen state,transitition E0Ef life time
E0 E
I(E) / 2
(E E0 )2 2 / 4
(t) 0e iE0t / e t / 2
E0
Ef
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Neutron-nucleus reactions
Solve Schrödinger equation of system to get cross sections.Shape of wave functions of in- and outgoing particles are known, potential is unknown. Two approaches:
• calculate potential (optical model calculations, smooth cross section)• use eigenstates (R-matrix, resonances)
Conservation of probability density:
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U R-matrix formalism
+
entrance channel
+
exit channelcompound nucleus
partial incoming wave functions:
partial outgoing wave functions:
related by collision matrix:
cross section:
Internal region (r<ac compound nucleus):• wave function is expansion of eigenstates .
External region (r>ac, well separated particles):• no interaction, Schrödinger equation solvable.
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Find the wave functions
separation distance
external region
internal region
match value and derivate of
Internal region: very difficult, Schrödinger equation cannot be solved directly solution: expand the wave function as a linear combination of its eigenstates.using the R-matrix:
External region: easy, solve Schrödinger equationcentral force, separate radial and angular parts.solution: solve Schrödinger equation of relative motion:
• Coulomb functions • special case of neutron particles (neutrons): fonctions de Bessel
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U The R-matrix formalism
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
D =100 keVSn =10 MeV
A+1X
AX
D =10 eVn +
En
En
Compound neutron-nucleus reactions
compound nucleus reaction
+
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
The R-matrix formalism
• The R-matrix formalism is adapted to describe compound nucleus reactions.
• Typically used for neutron-induced reactions at low energy (En<10 MeV, resonance region).
• The resonance parameters are properties of the excited nuclear levels:
- in the resolved resonance region (RRR), to each level (resonance) corresponds a set of parameters:
- in the unresolved resonance region (URR)average parameters are used:
10-3 10-1 101 103 105 107
En (eV)
tota
l cro
ss s
ecti
on thermal,
25 meV
resolvedresonances
unresolvedresonances
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
• A same set of resonance parameters is used to produce all resonant reactions,• at low energies mainly elastic scattering and capture (and fission).
• In a measurement, one does not measure a cross section, but a reaction yield or• transmission factor.
• The measured reaction yield is not equally sensitive to all parameters, additional• constraints can be necessary to extract RP from measurement.
Resonance parameters
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Neutron-nucleus reactions
Optical model calculations• gross structure• average cross sections• optical model potential • high energy, many channels
R-matrix resonance description• fine structure (resonances)• highly fluctuating cross sections• resonance parametrization• low energy, few channels
10-5 10-3 10-1 101 103 105 107 109
neutron energy (eV)
cap
ture
cro
ss
sect
ion
ne
utr
on
flu
x
thermalspectrum
stellarspectrum
whitesource
fissionspectrum
measurements calculations
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
197Au
neutron energy (eV)tota
l cro
ss s
ecti
on
(b
) thermal RRR URR
resonances, R-matrix
OMP
Compound nucleus reactions
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
6Li
27Al
55Mn
197Au
208Pb
241Am
neutron energy (eV)
tota
l cro
ss s
ecti
on
(b
)
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Statistical model
The nucleus in the vicinity of Sn is described by the Gaussian Orthogonal Ensemble (GOE)
The matrix elements are random variables with a Gaussian distribution.
• Consequences: • The partial width have a Porter-Thomas distribution. • The spacing of levels with the same Jπ have approximately a Wigner distribution.
0.0
0.2
0.4
0.6
0.8
1.0
0 1 2 3x = D / <D>
Wigner distribution
P(x
)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 1 2x =
i / <
i>
2=1
P(x
)
Porter-Thomas distribution
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Distribution of the spacing of two consecutive levels
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Distribution of neutron widths
N(t ) N(0) P(x)dxt
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Level density
Sn
Separated states are available- at low excitation energy
- in the region just above Sn
énergie d'excitation U
den
sité
de
niv
eau
x
Sn
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Known nuclei
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Known nuclei
stable
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Known nuclei
stable–
EC, +
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Level spacing D0
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I R F U Level spacing D0
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Level spacing D0
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Neutron separation energy
N
Z
4 - 10 MeVpour noyaux stables
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Neutron separation energy
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Fission of 235U+n and 238U+n
239U
238U
fissionactivation
Sn = 4.8 MeV
6.6 MeVn + 6.2 MeV
236U
235U
fissionactivation
Sn = 6.5 MeV
n +
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measurement of (n.xn) by gamma-ray spectroscopy
182W
181W
180W 6.7 MeV
8.1 MeV
gammasignature
excitationbyneutron
example: 182W(n,3n)180W
9/2+
0+
0+
183W
6.2 MeV
1/2–
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
0 1 2 3 4 5 6 7
E (MeV)
197Au(n,)In
ten
sité
rel
ativ
e
Simulated gamma-ray spectrum
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Moderation of neutrons
0.00 0.02 0.04 0.06 0.08 0.100
0.01
0.02
0.03
0.04
0.05
0.06
0.07
rela
tive
pro
bab
ility
dn
/dE
neutron energy (eV)
T = 300 K
thermal neutron spectrum
0 1 2 3 4 5 60.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
rela
tive
pro
bab
ility
neutron energy (MeV)
235U(nth
,f) emitted neutrons
H2O
moderator
Maxwell-Boltzmann velocity distribution: thermal neutrons:
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Evaluated nuclear data libraries
Libraries• JEFF - Europe• JENDL - Japon• ENDF/B - US• BROND - Russia• CENDL - China
Common format: ENDF-6
Contents:Data for particle-induced reactions (neutrons, protons, gamma, other)but also radioactive decay data
Data are indentified by “materials” (isotopes, isomeric states, (compounds) )ex. 16O: mat = 825 natV: mat = 2300 242mAm: mat = 9547
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U The library JEFF-3.1
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Files for a materialfrom report ENDF-102
1 General information 2 Resonance parameter data 3 Reaction cross sections 4 Angular distributions for emitted particles 5 Energy distributions for emitted particles 6 Energy-angle distributions for emitted particles 7 Thermal neutron scattering law data 8 Radioactivity and fission-product yield data 9 Multiplicities for radioactive nuclide production 10 Cross sections for photon production 12 Multiplicities for photon production 13 Cross sections for photon production 14 Angular distributions for photon production 15 Energy distributions for photon production 23 Photo-atomic interaction cross sections 27 Atomic form factors or scattering functions for photo-atomic interactions 30 Data Covariances obtained from parameter covariances and sensitivities 31 Data covariances for nubar 32 Data covariances for resonance parameters 33 Data covariances for reaction cross sections 34 Data covariances for angular distributions 35 Data covariances for energy distributions 39 Data covariances for radionuclide production yields 40 Data covariances for radionuclide production cross sections
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Example: part of an evaluated data file
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
A+1X
Ex
Neutron Capture Gamma-Ray Detection
A+1Xradioactive
• Activation- cross sections integrated over known neutron spectrum - applicable to some nuclei only- no time of flight
• Total energy detection- cEx, requires weighting function- neutron insensitive detector
example: C6D6 liquid scintillator
• Total absorption detection- requires = 4π, efficiency 100%- capture/fission discrimination in possible, example BaF2 total absorption
calorimeter
• Level population spectroscopy- applicable to some nuclei only- feasible with HPGe detectors,
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measuring a reaction yield using the time-of-flight technique
time zero
sample
production target,neutron source
reaction productdetector
flight length L
Pulse of charged particles
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measuring a reaction yield using the time-of-flight technique
sample
production target,neutron source
flight length L
reaction productdetector
Pulse of charged particles
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measuring a reaction yield using the time-of-flight technique
sample
production target,neutron source
flight length L
reaction productdetector
Pulse of charged particles
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measuring a reaction yield using the time-of-flight technique
sample
production target,neutron source
flight length L
time of flight t
reaction productdetector
Pulse of charged particles
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measuring a reaction yield using the time-of-flight technique
sample
production target,neutron source
flight length L
time of flight t
Kinetic energy of the neutron by time-of-flight
reaction productdetector
Pulse of charged particles
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
Resolution
The resolution can be expressed equivalenty in time, distance and energy:
• neutron time-of-flight:• flight length:• neutron kinetic energy:
Lt
neutronstart
neutronstop
Neutron time-of-flight experiment
distribution
time-energy relation
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measured reaction yield
isolated Breit-Wigner resonance, decaying quantum state with half-life =h/
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measured reaction yield
isolated Breit-Wigner resonance, decaying quantum state with half-life =h/
Doppler broadened
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measured reaction yield
resolution broadened andshifted
isolated Breit-Wigner resonance, decaying quantum state with half-life =h/
Doppler broadened
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Measured reaction yield
real measurement with background
Doppler broadened
isolated Breit-Wigner resonance, decaying quantum state with half-life =h/
resolution broadened andshifted
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Further Reading
Books/Papers• K. S. Krane, Introductory Nuclear Physics, Wiley & Sons, (1988).• G. F. Knoll, Radiation Detection and Measurement, Wiley & Sons, (2000).• P. Reus, Précis de neutronique, EDP Sciences, (2003).• J. E. Lynn, The Theory of Neutron Resonance Reactions, Clarendon Press, Oxford, (1968).• F. Fröhner, Evaluation and analysis of nuclear resonance data, JEFF Report 18, OECD/NEA (2000).• C. Wagemans, The Nuclear Fission Process, CRC, (1991).• A. M. Lane, R. G. Thomas, “R-matrix theory of nuclear reactions”, Rev. Mod. Phys. 30 (1958) 257.• G. Wallerstein, et al., “Synthesis of the elements in stars: forty years of progress”, Rev. Mod. Phys. 69 (1997) 995.
Web siteswww.nea.fr www.nndc.bnl.govwwwiaea.orgwww.cern.ch/ntof www.irmm.jrc.be
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Conclusion
• Neutron induced reactions are important nuclear data necessary for a wide range of fields ranging from nuclear structure and astrophysics to advanced nuclear technology applications.
• The R-matrix formalism is adapted to describe compound nucleus reactions at low energy (En<10 MeV, resonance region).
• Resolved resonances need to be measured accurately, they cannot be predicted by nuclear models.
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
Rapport de branchement 209Bi + n
209BiJπ=9/2+
210BiJπ=1–
Jπ=9–
– (5 d)
(3x106 y)
210PoJπ=0+ (138 d)
271 keV
210Bi*neutron
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U L’origine des déchets nucléaires
U (94.5%)
Pu (1%)autres actinides (0.5%)produits de fission (4%)
combustibleusé
238U (97%)
235U (3%)
combustiblefraisQuantité des déchets en France:
2500 kg/an par habitant dont 1 kg radioactif dont 20 g hautement radioactif
Loi Bataille:
recherche 1991 - 2006
• séparation et transmutation • stockage profonde • conditionnement et entreposage
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Réduire la radiotoxicité:la transmutation en complément de stockage
• produits de fission • actinides mineurs transmutation par capture de neutrons transmutation par fission induite par dans flux de neutrons thermique neutrons dans flux de neutrons rapide
Composition des déchetsClefs CEA 46 (2002)
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Réduire la radiotoxicité des déchets: le cylce du thorium
N
Z
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
99Tc
– (2x105 y)99Ru
100Tc
– (15.8 s) 100Ru
(n,)
100Tc*
– (12 h) 130Xe
129I
130I
– (1.6x107 y)129Xe
(n,)
130I*
Réduire la radiotoxicité des déchets: la transmutation
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U Produits de fission:temps de vie versus rendement
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
Resolution
GELINA (0o)n_TOF
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Frank Gunsing, CEA/Saclay Joint ICTP-IAEA Workshop on Nuclear Reaction Data for Advanced Reactor Technologies, Trieste, 26-5-2008
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I R F U
Resolution