Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
LA-UR-12-20350 Slide 1
How we can improve nuclear fission data for applications and fundamental
physics
Physics with Secondary Hadron Beams in 21st CenturyThe GWU Virginia Science and Technology Campus
Ashburn, Virginia, April 7, 2012
Alexander LaptevLos Alamos Neutron Science Center (LANSCE)
Neutron & Nuclear Science
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 2
Why neutrons?
High demand from nuclear industry for good quality data, first of all neutron-induced reaction cross sections for actinides and sub-actinides
- Development of new advanced nuclear reactors- Decreasing nuclear data uncertainties will decrease
nuclear reactor construction safety margins incorporated into reactor’s design
- Industry keeps developing: in Dec. 2011 NRC approved first nuclear power plant license since 1978 for the power plant expansion in Georgia
- Public pressure is as high as ever
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 3
Why neutrons (cntd)?
Defense physics needs Accelerator-based conversion of weapon’s grade
plutonium Transmutation of nuclear waste, especially actinides
Basic understanding of fission process, fundamental physics, etc.
- Yucca Mountain nuclear waste repository doesn’t accept new waste effective in 2011
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 4
Why a pulsed neutron source?
The most accurate and effective method to measure neutron energy is the time-of-flight method
Cartoon idea is from the KENS web-page
0.1 1 10 1000.00
0.05
0.10
0.15
En/E
n
En, MeV
t = 5 nsL = 20 m
Time-of-Flight (t)
TOF
Dist
ance
(L)
0
T
= T Wrap-around
τ
E1 E2
E3
Ew
Time
T1 T2 T3 Tw
Proton pulse injection
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 5
What is the energy range of interest?
Neutron flux shapes folded with cross sections determine the region of interest (both energy and isotopes)
The magnitude of the neutron flux drives cross section uncertainty requirements
10-2 10-1 100 101 102 103 104 105 106 107
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
U-238(ENDF/B)
Th-232(ENDF/B)
Pu-239(ENDF/B)
U-235(ENDF/B)
Thermal Reactor
Fiss
ion
Cro
ss S
ectio
n, b
arn
Neutron Energy, eV
Fast Reactor
109
1010
1011
1012
1013
1014
1015
Neu
tron
Flux
, n/(c
m2 ·s)
Fission Cross Section and Fluxes
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 6
History of neutron source development
Highlighted are active facilities in the US
IAEA-TECDOC-1439, 2005
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 7
Spallation sources: n/p yield and neutron energies (thick Pb target)
Report LA-4789, 1972NIM A 242 (1985) 121
NIM A 374 (1996) 70Preprint INR RAS 1280, 2011
Two components: - The cascade component up to the energy of the incident protons - The evaporation component which is dominant up to ~20 MeV
Ep = 800 MeV
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 8
Moderated neutron sources
NIM A 242 (1985) 121
Enrich neutron flux with epithermal neutrons- High content hydrogen material
is used for effective neutron moderation, e.g. polyethylene, water, etc.
- Varying of moderator thickness one can change the ratio of faster/slower neutrons
Time resolution of moderated source, GNEIS
Neutron flux of moderated source, LANSCE
Very specific moderator – liquid hydrogen – provides cold and ultra cold neutrons. This is a very unique field of neutron physics
PR C 79, 014613 (2009)
Details about this field are in the following report of S.Dewey
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 9
What facilities are available for fast neutrons?
WNR GNEIS n_TOF SNS J-PARC
Proton energy, MeV 800 1,000 20,000 1,000 3,000
Proton current, μA 1.8 2.3 0.5 1,400 300
Target W Pb Pb Hg Hg Number of produced neutrons per proton 10 20 250 25 75
Total neutron yield per second 1∙1014 3∙1014 8∙1014 2∙1017 1.5∙1017
Proton pulse length on target, ns 0.2 10 6 700 1,000
Pulse frequency, Hz 13,900 50 0.4 60 25
Handbook of Nuclear Engineering, Springer, 2010NIM A 242(1985)121
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 10
Existing 235U(n,f) XS data for fast neutrons
1 10 100 1000
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
235U 1955 Goldanskiy+ 1957 Smith+ 1963 Pankratov 1965 White 1975 Czirr+ 1976 Leugers+ 1978 Kari+ 1983 Alkhazov+ 1986 Alkhazov+ 1988 Johnson+ 1997 Lisowski+ 2007 Nolte+ Standard ver.1997 Standard ver.2007 JENDL/HE
Fiss
ion
cros
s se
ctio
n, b
Neutron energy, MeV
15%
The most popular detector is a parallel-plate fission ionization chamber (FIC)
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 11
Existing 239Pu(n,f) XS data for fast neutrons
Ref.: LANL(88): Lisowski et al., ND-1988(1988)97LANL(98): Staples et al., Nucl.Sci.Eng. 129(1998)149PNPI(02): Shcherbakov et al., J.Nucl.Sci.Tech. S2(2002)230LANL(10): Tovesson et al., Nucl.Sci.Eng. 165(2010)224
1 10 1001.4
1.6
1.8
2.0
2.2
2.4
2.6
10%
5.6%239Pu
LANL(88) LANL(98) PNPI(02) LANL(10) ENDF/B-VII.0 JENDL/HE
Fiss
ion
Cro
ss S
ectio
n, b
Neutron Energy, MeV
1%
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 12
Existing 238U(n,f) XS data for fast neutrons
1 10 1000.0
0.2
0.4
0.6
0.8
1.0
Present data Lisowski et al. [9] Recommended [13]
238U / 235U
Fiss
ion
cros
s-se
ctio
n ra
tio
Neutron energy, MeV
1 10 1000.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
238U
Lisowski+(1992) Shcherbakov+(2001) Nolte+(2007)
Neutron energy, MeV
Fiss
ion
cros
s se
ctio
n, b
7%
Data were taken using FIC as a ration to 235U (LANL and PNPI)
Data of Nolte were obtained relative to np-scattering
Ref.: Lisowski: Lisowski et al., ND-1991(1992)732Shcherbakov: Shcherbakov et al., J.Nucl.Sci.Tech. S2(2002)230Nolte: Nolte et al., Nucl.Sci.Eng. 156(2007)197
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D
Existing data for fast neutron-induced fission of some minor actinides
Slide 13
From the NEA Nuclear Data High Priority Request List for fission cross section of minor actinides
Requested accuracy is defined by the Accelerator-Driven Minor Actinides Burner (ADMAB)
245Cm Initial vs target uncertainties (%)
Energy Range Initial ADMAB 2.23 - 6.07 MeV 31 7 1.35 - 2.23 MeV 44 6
0.498 - 1.35 MeV 49 3
llllll
244Cm Initial vs target uncertainties (%)
Energy Range Initial ADMAB 6.07 - 2.23 MeV 31 3 2.23 - 1.35 MeV 44 3
1.35 - 0.498 MeV 50 2
0.1 1 10 1000.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
244Cm
Fursov+, 1997 Fomushkin+, 1991 Vorotnikov+, 1981 Fomushkin+, 1980 Moore+, 1971 Koontz+, 1968 Fomushkin+, 1967 ENDF/B-VII.0 JEFF-3.1 JENDL-3.3 JENDL/AC-2008
Fiss
ion
cros
s se
ctio
n, b
Energy, MeV0.1 1 10 100
0.5
1.0
1.5
2.0
2.5
3.0
3.5
245Cm
Fursov+, 1997 Ivanin+, 1997 Fomushkin+, 1991 Fomushkin+, 1987 White+, 1982 Gokhberg+, 1972 Moore+, 1971 ENDF/B-VII.0 JEFF-3.1 JENDL-3.3 JENDL/AC-2008
Fiss
ion
cros
s se
ctio
n, b
Energy, MeV0.1 1 10 100
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Fursov+, 1997 Fomushkin+, 1991 Fomushkin+, 1980 Moore+, 1971 ENDF/B-VII.0 JEFF-3.1 JENDL-3.3 JENDL/AC-2008
Fiss
ion
cros
s se
ctio
n, b
Energy, MeV
248Cm
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 14
Systematic errors associated with conventional FICs1. Separation of fission and background events in pulse-
height spectra:
2. Anisotropy of emitted fission fragments3. Neutron flux normalization: mostly data were obtained from
235U ratio, very few were normalized to (n,p)-scattering 4. Beam profile and sample uniformity5. Charged particle contamination of neutron beam6. …
- Spallation and fragmentation inputs- Radioactivity of used targets- Electronic noise
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D
Fission fragment track
Alpha particle track
Slide 15
TPC can address most of the systematic uncertainties associated with conventional FICs Time Projection Chamber (TPC)
technology based on highly pixelated readout anodes
Full 3D event reconstruction gives a “snapshot” of ionization tracks in a fill gas
Particle identification based on specific ionization loss
The TPC experiment, involving a collaboration of 4 national labs and 6 universities, is currently running at the fast neutron beam facility WNR at LANL
There are more details in following report of F.TovessonRef.: Heffner, AIP Conf.Proc. 1005(2008)182
Alpha particle
Fission fragment
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 16
Other ways to avoid systematic uncertainties associated with conventional FICs An ionization fission chamber with gaseous
actinide target doesn’t lose fission fragments emitted at steep angles
Uranium hexafluoride UF6 can be a suitable compound for investigating U isotopes as it has a boiling point at 56.5oC
Ref.: Laptev, Strakovsky, Briscoe, Afanasev, Proposal NSF-ARI-MA (DNDO) Grant ECCS-1139985, 2011
- There is no “edge-effect” due to two fragment emission- It is expected much better resolution between fission
fragments and small PH signals in a pulse height spectrum
- Separate active volume outside the main one should be used for the background neutron input estimation
For the Pu isotopes, plutonium hexacarbonyl Pu(CO)6 can be considered.
Ref.: Thanks to W.Loveland, Oregon State University,for pointing out this opportunity
Neutron beam
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 17
Prompt Fission Neutron Study
Ref.: Noda, Haight et al., Phys.Rev.C 83, 034604 (2011)
- Parallel plate avalanche counter as a fission trigger- 20 6Li-glass detectors to measure neutron output below
1 MeV- 50 liquid scintillator detectors to measure neutron
output from 0.5 to 12 MeV
~35 % less than 1 MeV
Importantregion for
rad-chem: (n,2n) etc.
Existing data establish the prompt fission neutron spectrum quite well in the energy range from 1 to about 5 MeV
The Chi-Nu experiment to study the prompt fission neutron spectrum will also run at the WNR
Chi-Nu goals are - Below 1 MeV, to reduce the neutron output uncertainties
from ~10% to ~5%- Above 6 MeV, to reduce uncertainties from 20-50% to
10-20%
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 18Slide 18
Angular distribution of PFN relative to FF
Ref.: A.Vorobyev et al., NIM A 598 (2009) 795
Recent measurement for thermal neutrons
Fission neutrons from the 235U(nth,f) reaction were detected at several angles
Angular resolution is 18o
Model calculation was done on the basis of the assumption that neutrons are emitted only from fully accelerated fragments
Obtained an estimate of upper limit for “scission” neutrons less than 5% of the total neutron output
From all existing works: the contribution of scission neutrons to the total yield of PFN ranges from 1% to 20%, so even existence of “scission” neutrons can hardly be considered proven
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 19
Fission fragment yield distribution
The fission fragment yield distribution changes drastically with neutron energy above ~10 MeV, from asymmetric to symmetric
There are no data above neutron energy of about 20 MeV except for 238U and 232Th. No data for the most important nuclei 235U and 239Pu !
These data are vitally important for both fission theory and many applications including fast reactors, ADS systems, and special nuclear devices
This gives strong motivation for the new LANL experiment SPIDER, designed to obtain fission fragment yields with mass resolution up to 1 amu following fast neutron-induced fission
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 20
Existing data for fission fragment yield distribution as a function of neutron energy for 232Th
Ref.: Simutkin et al., AIP Conf.Proc. 1175(2009)393
The fission fragment yield distribution experiences drastic change in the energy range from 10 to 60 MeV
FF mass resolution is ~ 8 amu
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 21
High resolution fission fragment yield measurements Measured at ILL,
France for thermal neutron
FF yield Nuclear charge
distribution for A=87
229Th(nth,f) with COSI-FAN-TUTTE spectrometer
SPIDER experiment to measure energy-dependent neutron-induced FF yields with high resolution in progress at LANL
There are more details about SPIDER in following report of F.Tovesson
FF mass resolution is expected ~1 amu
FF mass resolution is ~ 0.64 amu
Ref.: White, Tovesson et al., Report LA-UR-11-01125
Ref.: Boucheneb et al., Nuc.Phys.A 502(1989)261c
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D
Fission fragment mass distribution for fixed numbers of emitted neutrons νL / νH for spontaneous fission of 248Cm
There are no such data for fast neutron-induced fission. The very first attempt of such measurement was done for thermal and 0.3 eV neutron induced fission of 235U and 239Pu [Batenkov et al., AIP Conf. Proc. 769 (2005)1003]
Fission theories are most sensitive for correlated data, source: LANL-LLNL fission workshop, Feb 3-6, 2009
Slide 22Slide 22
Correlation between PFN multiplicity & FF properties
Ref.: V.Kalinin et al., Fission: Pont d’Oye V (2003)73
Search for correlation between PFN multiplicity & FF properties in SF of 252Cf, 244Cm, and 248Cm was done using a 4π neutron detector and twin Frisch gridded FIC
FF mass resolution is ~ 1.5 amu (for 252Cf)
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 23Slide 23
Average fission neutron multiplicity
0 20 40 60 80 100 120 140 160 180 2000
2
4
6
8
10
12
14
Howe(1984) Ethvignot+(2005)A
vera
ge N
eutro
n M
ultip
licity
Incident Neutron Energy, MeV
235U
0 20 40 60 80 100 120 140 160 180 2000
2
4
6
8
10
12
14
Frehaut(1980) Taieb+(2007)A
vera
ge N
eutro
n M
ultip
licity
Incident Neutron Energy, MeV
238U
Ref. (238U):J.Frehaut , EXFOR data 21685.003J.Taieb et al., ND-2007 (2007)429
Ref. (235U):R.Howe, Nucl.Sci.Eng. 86(1984)157T.Ethvignot et al., PRL 94(2005)052701
Average fission neutron multiplicity as a function of incident neutron energy is known quite well for nuclei 235U, 238U, and 237Np, up to 200 MeV
For other nuclei important to the nuclear cycle the data are limited: for 232Th < 50 MeV, 239Pu < 30 MeV, 233U < 15 MeV, 243,241Am < 11 MeV, etc.
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 24Slide 24
Total kinetic energy of fission fragments as a function of neutron energy
Ref.:Data: C.Zöller, PhD Theses (1991)Fit: D.Madland, NP A 772(2006)113
Data on total kinetic energy of fission fragment are required for both theory and applications to calculate total energy release in fission (along with that for
The quadratic fit doesn’t describe structure near different chance fission thresholds because the corresponding experimental data for 235U and 239Pu are much lower in quality and the energy range is limited (no data above 15 MeV)
0 5 10 15 20 25 30167
168
169
170
171
172
Zoeller (1991) Fit
Tota
l Kin
etic
Ene
rgy,
MeV
Incident Neutron Energy, MeV
238UPre prompt neutron emission
prompt and delay fission neutron, prompt and delay fission gamma-ray energy, etc.)
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 25
Angular anisotropy of fission fragments
Ref.: Ouichaoui et al., Acta Phys.Hung. 64(1988)209Shpak, Yadernaya Fizika 50(1989)922
-30 0 30 60 9040
60
80
100
120
140
Ouichaoui+(1988) Fit ao+a2cos2Lab
d/d,
mb/
sr
Lab, deg
238UEn = 14.1 MeV
1 100.8
1.0
1.2
1.4
1.6
1.8
2.0
Ouichaoui+(1988) Shpak(1989) Other data(<1981)
d/d(
0o ) / d/
d(9
0o )
En, MeV
238U
It is used in fission cross section measurements to calculate a correction for FF absorption in a target
Provide information about the projection of the total angular momentum J of the fissioning nucleus along the nuclear symmetry axis at saddle point deformation
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 26
Ternary fission yields Important for both fission theory and applications (gas emission
characteristics) Studied quite well at thermal
energy:
Confident separation of all ternary particles in SF 252Cf [M.Mutterer et al., PR C 78(2008)064616]
E-distribution for the 235U(nth,f) ternary α’s
- 235U ratio binary/ternary fission was measured quite well: 536±10 [C.Wagemans et al., PR C 33(1986)943];
- energy distribution of ternary α’s measured[C.Wagemans et al., NP A 742(2004)291];
- etc.
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 27
Prospective investigations of ternary fission Very little data for fast neutron-induced fission. Better
understanding needed of:- Variation of ternary-to-binary fission ratios in the resonance energy
region. E.g., a correlation of ternary fission yields and the relative contribution of standards I and II fission modes was found in 235U(n,f) resonances at energy from thermal to 2500 eV [S.Pomme et al., NP A 587(1995)1]
- Angular anisotropy in ternary nuclear fission and its dependence on neutron energy. Most fission theories predict ternary particles to be formed at scission. A way to confirm this assumption is to analyze the angular distribution of fission fragments[S.Dilger, PhD Theses(2004)]
- “Quaternary” fission with an apparently independent emission of two charged particles?[M.Mutterer, Pont d'Oye V (2003)135]
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 28Slide 28
Subthreshold fission as a search for class-II states
Ref.: Auchampaugh, Weston, PRC 12, 1850 (1975)
Gives unique information about fission barriers Direct demonstration of double-humped
structure of potential energy of heavy nuclei and existence of class-II states
First systematic study of class-II clusters with high energy resolution was done at the ORELA facility, ORNL for 240Pu
The double-humped fission barrier
Ref.: Mughabghab, Atlas of Neutron Resonances, 2006
Clustering of subthreshold fission strengths observed in 240Pu was explained in terms of the double-humped fission theory
Average level spacing of class-II states estimated of DII = 450±50 eV. Based on that and known DI, a value of EII = 1.52±.08 MeV was derived
1936 eV cluster in subthreshold fission of 240Pu
Clustering of fission strengths
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 29Slide 29
Search for γ-transitions to class-II states
Ref.: O.Shcherbakov et al., ASAP Proc. (2002) 123
Differences in pulse-height γ-ray spectra for weak (Γf < 10 meV) and strong (Γf > 10 meV) fission 1+‑resonances of 239Pu in epithermal neutron energies
Few possible structures could be interpreted as a γ-transitions between class-II states
Confident discovery of class-II γ-transitions will give unique information about the structure of the fission barrier
Descriptive schematic of the (n, γf) reaction mechanism
Ref.: J.Trochon, Physics & Chemistry of Fission, 1979, Vol. I, p.87
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D
1 10 100 1000 10000
0.5
1.0
1.5
2.0
235U(n,f), Standard ver. 2007 235U(n,f), JENDL-HE 235U(p,f), JENDL-HE 235U(p,f), Kotov+, 2006 235U(p,f), Yurevich+, 2002 235U(p,f), Ohtsuki+, 1991 235U(p,f), Bochagov+, 1978 235U(p,f), Boyce+, 1974 235U(p,f), Brandt+, 1972 235U(p,f), Matusevich+, 1968 235U(p,f), Konshin+, 1965 235U(p,f), Fulmer, 1959 235U(p,f), Steiner+, 1956 235U(p,f), McCormick+, 1954
Fiss
ion
cros
s se
ctio
n, b
Incoming Particle Energy, MeV
Fission cross section of 235U
Slide 30
Proton-induced fission of 235U This energy range is important
for future ADC systems, e.g., for transmutation of nuclear waste
Existing data are very scarce and are in contradictory
The ALICE code calculation for the JENDL-HE data file shows a peak near 300 MeV, which comes from a broad reaction cross section shape from the optical model [Private communication from T.Kawano, 2009]. New experimental data are needed to confirm that result
Relevant proton energy range should be available for the JLab EIC booster
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 31
Single-event effects (SEEs) in electronics investigations Increasing complexity and density of an electronic
chips increases their susceptibility to cosmic radiation. Most SEEs in avionic electronics at aircraft cruising altitudes are caused by neutrons
Electronics industry is very interested in checking the stability of their electronics against neutron irradiation
Spallation neutron sources can imitate cosmic neutron flux but with intensities millions of times higher
Many facilities all around the world built irradiation facilities, which are in high demand
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 32
Active facilities in SEEs studies Neutron flux of the ICE House
irradiation facility at LANL
Neutron flux of the irradiation facility at GNEIS
Facility Affiliation Energy, MeV*) Neutron source Ref.
ICE House LANL, USA 800(p) White spectrum J.Korean Phys.Soc. 59 (2011) 1558
TRIUMF Neutron Facility TRIUMF, Canada 70-500(p) White spectrum
IEEE Radiation Effects Data Workshop, 2003,
p.149
ANITA The Svedberg Lab.,
Uppsala Univ., Sweden
180(p) White spectrum IEEE Radiation Effects Data Workshop, 2009,
p.166
VESUVIO Rutherford Appleton Laboratory, UK 800(p) White spectrum Appl. Phys. Lett. 92,
114101 (2008)
GNEIS PNPI, Russia 1,000(p) White spectrum Instrum. Exper. Tech. 53 (2010) 469
RCNP Research Center for
Nuclear Physics, Osaka Univ., Japan
14-198(n) Quasi-monoenergetic
42nd Annual IEEE Int. Reliability Physics Symp.,
2004, p.305
…
*) (p) indicates proton beam energy on spallation target;
(n) energy of neutron beam is shown. With the EIC booster proton energy of 3,000 MeV
it may be possible to obtain better imitation of cosmic-ray neutron spectrum to higher energies
Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA
U N C L A S S I F I E D Slide 33
Summary
In many years of fission research, a large volume of experimental data was accumulated
There is still a significant lack of fission data for fast neutrons. Improving the quality of existing data will make a crucial impact on important applications and nuclear theory
The proposed EIC complex at JLab promises to be a facility for acquiring high-quality experimental fission data and to carry out applied research