Studies of Deuteron and Neutron Cross-sections Important for ADS Research
Vladimír Wagner
Nuclear physics institute of CAS, 250 68 Řež, Czech Republic, E_mail: [email protected]
for collaboration “Energy plus transmutation”
(Russia, Belarus, Germany, Greece, Poland, Ukraine, Czech Republic …)
XXI INTERNATIONAL BALDIN SEMINAR ON HIGH ENERGY PHYSICS PROBLEMS
(XXI Baldin seminar)
Deuteron reaction cross-section measurements Neutron reaction cross-sections measurements
Production of 24Na on aluminum foil by deuteron beam
Only about this reaction are cross-section data, but only scarce. → uncertainty 10 %
2 GeV deuterons
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
0 1 2 3 4 5 6
De
ute
ron
inte
gra
l [1
013
de
ute
ron
s]
4 GeV deuterons
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
0 1 2 3 4 5 6
De
ute
ron
inte
gra
l [1
013
de
ute
ron
s]
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
2.4
2.5
0 1 2 3 4 5 6
De
ute
ron
inte
gra
l [1
013
de
ute
ron
s]
6 GeV deuterons
Beam integral determination by means of aluminum foils
2 GeV 1.54(7)·1013 deuterons4 GeV 1.39(4)·1013 deuterons6 GeV 1.97(10)·1013 deuterons
Cross-section uncertainty – 10 %
December 2011 set of QUINTA irradiations
Very good agreement – we have approved values
1.40E+131.42E+131.44E+131.46E+131.48E+131.50E+131.52E+131.54E+131.56E+131.58E+131.60E+13
0 1 2 3 4 5 6 7 8 9
Number of measurement [-]
Beam
inte
nsity
[-]
1.75E+13
1.80E+13
1.85E+13
1.90E+13
1.95E+13
2.00E+13
2.05E+13
2.10E+13
2.15E+13
0 2 4 6 8 10 12
Number of measurement [-]
Beam
inte
nsit
y [-
]December 2011 irradiations
1 GeV deuterons
4 GeV deuterons
1 GeV 1.533(9)·1013 deuterons4 GeV 1.932(10)·1013 deuterons
Only statistical uncertainties
Zhuk:
1 GeV 1.47 ·1013 4 GeV 1.96 ·1013
Necessary – all data with uncertaintiesDescription of all correction calculation (coincidences, self absorption, size of sample)
March 2012 irradiations
1.80E+131.82E+131.84E+131.86E+131.88E+131.90E+131.92E+131.94E+131.96E+131.98E+132.00E+13
0 1 2 3 4 5 6 7 8
Number of measurement [-]
Beam
inte
nsity
[-]
2.60E+13
2.65E+13
2.70E+13
2.75E+13
2.80E+13
2.85E+13
2.90E+13
2.95E+13
3.00E+13
0 1 2 3 4 5 6 7 8
Number of measurement [-]
Beam
inte
nsity
[-]
1 GeV deuterons
4 GeV deuterons
Energy Number of deuterons
1 GeV 1.886(8)·1013
4 GeV 2.796(26)·1013
8 GeV 0.565(6)·1013
Only statistical uncertainties
1 GeV 4 GeV 8 GeV
Zhuk 1.9 2.7 0.37KH1 1.8 3.5 0.49KH2 1.8 2.7 0.37JINR 1.87(10) 2.65(13) 0.55(4)
Preliminary
Studies of relativistic deuteron reactions on natural copper
Common irradiation of aluminum and copper foils
Production of different radionuclides
2.0E+08
2.1E+08
2.1E+08
2.2E+08
2.2E+08
2.3E+08
2.3E+08
2.4E+08
2.4E+08
0 2 4 6 8 10
yie
ld o
f ra
dio
nu
clid
e
52Mn 744 keV
March 2012 – 4 GeVMore measurements of copper sample in different times (possibility split influence of short lived and long lived isotopes with the same energy line – 43K and 43Sc, 56Co and 56Mn, 48Sc and 48V) and on different detectors with different geometry (suppression of systematic uncertainties influence)
Some deuteron energies were measured more times
Energy range of deuteron beam from 1 GeV up to 8 GeV
Comparison of different measurements with the same deuteron energy
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
0 2 4 6 8 10 12 14
Ra
tio
of
1 G
eV
me
as
ure
me
nts
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
0 2 4 6 8 10 12 14
Ra
tio
of
4 G
eV
me
as
ure
me
nts
Comparison of two measurements with 1 GeV neutron beam1. December 20112. March 2012
Mean value of ratio: 0.969
Comparison of three measurements with 4 GeV neutron beam1. March 20112. December 20113. March 2012
Mean value of ratio: 1./2. 0.8843./2. 0.926
57Ni, 58Co, 56Co, 55Co, 56Mn, 52Mn, 48Cr, 48V, 48Sc, 47Sc, 44mSc, 43Sc and 43K
Obtained deuteron reaction cross-sections on natural copper
58Co
15.0
20.0
25.0
30.0
35.0
40.0
45.0
0 1 2 3 4 5 6 7 8 9
Deuteron energy [GeV]
Cro
ss-s
ectio
n [m
barn
]
52Mn
4.0
6.0
8.0
10.0
12.0
14.0
16.0
0 1 2 3 4 5 6 7 8 9Deuteron energy [GeV]
Cro
ss-s
ecti
on
[m
bar
n]
43K
1.0
1.5
2.0
2.5
3.0
0 1 2 3 4 5 6 7 8 9Deuteron energy [GeV]
Cro
ss-s
ecti
on
[m
bar
n]
57Ni
0.5
0.7
0.9
1.1
1.3
1.5
0 1 2 3 4 5 6 7 8 9Deuteron energy [GeV]
Cro
ss-s
ecti
on
[m
bar
n]
BeamBeam-line-line
Li-targetLi-target
GraphiteGraphite stopper stopper
SamplesSamples
Measurement of neutron reaction cross/sections
Quasi-monoenergetic neutron source:protons from cyclotron + lithium target
NPI ASCR Řež: Energy range 18 -37 MeV, neutron intensity ~ 108 neutron cm-2 s-1
TSL Uppsala: Energy range 25 – 200 MeV neutron intensity ~ 105 neutron cm-2 s-1
Advantage of two neutron sources: very wide energy range, partial overlap – better estimation of systematical uncertainties
380.79 keV
9/2+
1/2-
87mY
ε+β+87Y
98.43(10) % 1.57(10) % <<
ε+β+
T1/2 = 13.38 hours
T1/2 = 79.8 hours
Yttrium cross-section measurement
Reaction (n,3n) - production of isomeric and ground state of 87Y
Yttrium – good material for activation detectorUsed by “Energy+Transmutation” collaboration
Very scare data about cross-sections
Methodical measurement – neutron energy 32.5 MeV (only reactions (n,2n) and (n,3n)), May 2011, to prepare systematic study of yttrium reactions using the NPI neutron source
No data about cross-sections of isomeric state production
Long irradiation, intensive beam, only limited number of samples → possibility to measure yttrium sample many times to study systematic uncertainties of gamma measurements
Concentration on isomeric state 87mY
tt eNeNNN
12
0121
101
21
1022
teNN 1011
87mY 87Y
0
2000000000
4000000000
6000000000
8000000000
10000000000
12000000000
14000000000
16000000000
0 50 100 150 200
Time after end of irradiation [hours]
Nu
mb
er
of
rad
ioa
cti
ve
nu
cle
i [1
09 ]
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
N02
N01
♦ - 87mY
■ - 87Y
N = N01exp(-λ1t)
N = N01exp(-λ2t)
teNNN
2
0121
102
Experimental points
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
0 200 400 600 800 1000
Time after end of irradiation [hours]
Nu
mb
er
of
rad
ioa
cti
ve
nu
cle
i teNNN
2
0121
102
Experimental points
■ - 87Y
♦ - 87mY
N = N01exp(-λ1t)
tt eNeNNN
12
0121
101
21
1022
teNN 1011
87mY 87Y
N01= 6.05(8)109
9
0121
102
10)11(38.14
NN
N02= 7.12(21)109
0
100
200
300
400
500
600
700
800
900
0 10 20 30 40
Neutron energy [MeV]
cros
s-se
ction
[mba
rn] 87mY
87Y
87gY
Higher threshold near to neutron energy → 93 % of radioactive nuclei is produced by peak, only 7 % by background
Cross-section of 87mY and 87gY
89Y(n,3n)87Y case
89Y(n,2n)88Y case
Uncertainties of proton beam integral and neutron spectra description are about 10 - 15 % > gamma spectroscopy uncertainties
Background production subtraction
σ(87mY) = 578(56) mbarn
σ(87gY) = 203(25) mbarn
87Y - EXFOR
squares - our datalines - TALYS
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
0 5 10 15 20 25 30 35 40Neutron energy [MeV]
Cro
ss-s
ecti
on [
barn
]
EXFOR
TALYS 1.2
our data
88Y
Reaction 89Y(n,2n)88Y
Neutron peak - only 34.8 % of production, 65.2 % of radioactive nuclei produced by background
New measurements next weeks
New measurements of neutron cross-section on yttriumtogether with Polish colleagues
Improvements:
1) Every irradiations two yttrium samples, one foil and one pressed tablet
2) Big number of measurements of every sample (very important for isomeric state measurement)
3) Measurement in different sample distance to detector
Measurement is in the framework ofERINDA
Four irradiations:
First two during weekend:
Energies 18 and 35 MeV
Next two during first half of October:
Energies 26 and 29 MeV
Conclusions
• Many cross-sections of deuteron and neutron reactions with different materials are needed (very scarce data at experimental data bases).
• We used Quinta measurements to obtain cross-sections of relativistic deuterons reactions on copper.
• The crucial is determination of beam integral (for all data). The common analysis of all monitor data and determination of common final of beam integral is necessary. We made this only fo first Quinta irradiation (March 2011)
• The set of thirteen reactions on copper was studied and cross-sections were determined within energy range from 1 GeV up to 8 GeV.
• The quasimonoenergy neutron sources are ideal possibility to obtain cross-sections of reactions which we use for activation measurement of neutron field.
• We started set of measurements of yttrium samples together with our Polish colleagues. The ERINDA project and NPI Rez neutron source are used.
BIG THANKSto students
Diploma and PhD students:
Ondřej Svoboda Jitka Vrzalová
Martin SuchopárPetr Chaloupka
Other students:
Ondřej SlámaAnne Laredo
Daniel Wagner
and also all colleagues
and JINR Dubna Nuclotronpeople