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Nuclear physics activities in Lithuania
Arturas PlukisInstitute of Physics,
Savanoriu pr. 231, Vilnius, 02300Lithuania
www.fi.lt
Institute of Theoretical Physics and Astronomy
• Department of Theory of Nucleus has been established in 1973 by V. Vanagas.
• Investigate the light nucleus as quantum Skyrme model solitons
• Calculations of deuteron and helium form factors
• neutrino interactions with nuclei as well as electron-capture rates in the supernova environment
Institute of Theoretical Physics and Astronomy
• collaboration with K.Langanke,G.Martinez-Pinedo (both GSI,Germany), and W.R.Hix (ORNL, USA)
• collaboration with F.Nowacki (IReS, France) and G.Martinez-Pinedo
Vytautas Magnus university, Kaunas
• Techniques for microscopic nuclear theory development
• Modification of the nucleon-nucleon interaction because of surrounded“spectator” nucleons
A. Plukis, Oct 17, 2008, Vilnius
Institute of PhysicsNuclear and environmental radioactivity
research laboratory
• 40 Employees– 20 with doctor or hab. doctor degree– 8 PhD students
• Radiochemical laboratory• Nuclear spectroscopy facilities• “Tandetron” ion accelerator• Ignalina Radioecological Monitoring
Station
A. Plukis, Oct 17, 2008, Vilnius
Nuclear theory group
• Ab initio microscopic nuclear structureinvestigations for light nuclei:harmonic oscillatorbasis, translationaly invariant and antisymmetricwave function, realistic nuclear Nucleon-Nucleoninteraction (Reid, Argonne, Nijmegen)
• Parallel code, MPI and FORTRAN• Participation in LitGRID distributed computing
network• Collaboration with Arizona university (prof. B.
Barrett), Vytautas Magnus university
A. Plukis, Oct 17, 2008, Vilnius
Experimental nuclear spectroscopy
• Activity started by prof. K.Makariūnas
• Influence of chemical environment on radioactive decay (electron capture, internal conversion) rate.
• Hyperfine interactions (PAC, Mössbauer spectroscopy)
• Applied nuclear physics
A. Plukis, Oct 17, 2008, Vilnius
57Co decay rate variations
Compound CoS CoCl2 Co Co(Pd) CoSO4
(Δλ/λ)⋅104 -2.9 ± 0.4 -1.1 ± 0.4 0.0 ± 1.1 2.0 ± 1.1 5.6 ± 1.2
57Co EC Δλ/λ values compared to Co metal
A. Plukis, Oct 17, 2008, Vilnius
Measurement of electron density chemical changes on In nucleus by ΔΙγ/Ιγ method
A. Plukis, Oct 17, 2008, Vilnius
Calibration of 127I ir 129I Mossbauer isomer shift by 125I decay
rate variations (Δλ/λ)
Juodis L., Plukis A., Remeikis V., and Makariūnas K.,EPL 53 (3) , p. 283 (2001)
-8 -6 -4 -2 0 2 4 6 8
0.995
1.000
0.995
1.000
v, mm/s
A. Jagminas, K. Mažeika, J. Reklaitis, M.Kurtinaitienė, D. Baltrūnas: Template synthesis,characterization and transformations of ironnanowires while aging, Materials Chemistry andPhysics 109, (2008) 82-86.
Influence of annealing to Mössbauer spectra of Fe nanowires in AAO matrix
Mössbauer spectrometer with closed cyclehelium cryostat used for the studies ofbiomolecular objects, amorphous andsemiconductor, ferroelectric andnanocrystalline materials.
Mössbauer spectroscopy
Rayleigh scattered Mössbauer spectroscopy
0 10 20 30
0
500
1000
1500
2000
2500
3000
3500
4000
Research of macromolecule dynamics
-6 -4 -2 0 2 4 60,65
0,70
0,75
0,80
0,85
0,90
0,95
1,00
1,05
1,10
Rel
ativ
e in
tens
ity
velocity, mm/s
A. Plukis, Oct 17, 2008, Vilnius
Tandetron 4110A accelerator
H, C, Si, Fe ions from 2 to 5 MeVCurrents up to 2 particle μAPIXE, NRA, RBS analysis
A. Plukis, Oct 17, 2008, Vilnius
EU FP6 EurisolDS project
• European new generation RIB facility• Mostly participation in Task 5 “Safety and
Radioprotection”• Main target shielding calculations• Activation and radionuclide transport
evaluation• Spent target disposal and decomisioning
issues
A. Plukis, Oct 17, 2008, Vilnius
Neutron flux in Eurisol multi MW target
With CEA and PNPI
EPJ A, v,32, 1 p.1 (2007)
A. Plukis, Oct 17, 2008, Vilnius
Nuclear energy related activities
• Expert support for VATESI, RATA, Ministry of Environment
• Irradiated nuclear fuel composition• Radioactive waste analysis• Monitoring of radionuclides in environment
A. Plukis, Oct 17, 2008, Vilnius
Code validation for RBMK SNF calculation
(fuel assembly 3D description)
2% enrichment 235U fuelinner and outer fuel pellet ringsvertically varying coolant density along
the fuel channel
6.86
m
0.75171.5D, D2
0.55343C, C2
0.33514.5B, B2
0.25686A, A2
ρ (H2O) g/cm3h, cm
Axial region
h
A. Plukis, Oct 17, 2008, Vilnius
RBMK nuclear fuel composition239Pu content in irradiated fuel
A. Plukis, Oct 17, 2008, Vilnius
CASTOR cask modelling with MCNP5(3D geometry description)
CASTOR container No.0067-14102 half-assemblies located at specified places of CASTOR cask using hexagonal lattice option
3.43
m4.
4m
A. Plukis, Oct 17, 2008, Vilnius
MCNP5 Gamma dose average is 39 Sv/hSCALE 4.3 average is 52 Sv/h experimental dose points are ~1.6 times above the MCNP5
result is rather good taking into account a) uncertainties of our model:
spent nuclear fuel composition, irradiation and cooling history, Co contents in the fuel cladding, etc.
b) possible surface contamination with fission products from the cooling poolc)TLD sensitivity to thermal neutronsd) SCALE 4.3 after ~10 years and our work after 13 years
Gamma dose rate at the CASTOR surface
A. Plukis, Oct 17, 2008, Vilnius
Generation IV reactors for transmutation (collaboration with CEA)
- Fuel - Erbium - Helium - Graphite
310μm
200μmCore contains : 1.87×1010 ÷ 3.18×1010 fuel particles
1.5×108 ÷ 3.4×109 burnable poison particles
3D GT-MHR geometry descriptioncompact and particle levels (R.Plukiene)
A. Plukis, Oct 17, 2008, Vilnius
239Pu burnup in GT-MHR:WG Pu - 73%PWR Pu - 82%RBMK Pu1 - 93%RBMK Pu3 - 90%
GT-MHR:WG Pu, PWR Pu and RBMK Pu1 fuel cases
(burnup)
Fusion – fission hybrid system simplified neutronic model (collaboration
with CEA Saclay and TSI Research)
Molten salt liquid wall
Fusion system
D + T= 4He + n ( 14MeV)
External neutron source(1MW ~ 4·1017 n/s )
Molten salt blanket with TRU(LiF-BeF2-(HN)F4)HN (Pu + MA)
fission capture
1 group cross sections for actinides
A. Plukis, Oct 17, 2008, Vilnius
Nuclear spectroscopy for materials identification
• Participation in nuclear smuggling ITWG– Pu Round-robin test
• Forensic analysis for illegal nuclear materials– Depleted uranium– RBMK and VVER fuel pellets
A. Plukis, Oct 17, 2008, Vilnius
Pu in SNFU in fresh nuclear fuel
A. Plukis, Oct 17, 2008, Vilnius
Scaling factors for Ignalina NPP radioactive waste
• Experimental and modeling determination of difficult-to-measure nuclides
– Very low level waste
– Liquid radioactive waste
– Bituminized waste
– Waste characterization for decomissioning activities
• Graphite waste characterization (FP7 “Carbonwaste” project)
A. Plukis, Oct 17, 2008, Vilnius
Difficult to measure nuclides in bitumenized Ignalina NPP waste
A. Plukis, Oct 17, 2008, Vilnius
SNF
Solid waste
Liquid waste
Future
• Old RBMK reactor will be decomissioned for some period Lithuania will be non nuclear country
• “A New Hope” - new reactor is planed– Studies reactor and neutron physics in Vilnius
University
– Great popularity among students
– Experimental labs are foreseen
A. Plukis, Oct 17, 2008, Vilnius
Thank You for attention