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Advanced neutron spectrometers for condensed matter studies at the IBR-2M reactor

Advanced neutron spectrometers for condensed matter studies at the IBR-2M reactor. Anatoly M. Balagurov Frank Laboratory of Neutron Physics, JINR, Dubna, Russia . Neutron scattering for condensed matter science. IBR-2M pulsed reactor as a neutron source of third generation.

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Advanced neutron spectrometers for condensed matter studies at the IBR-2M reactor

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  1. Advanced neutron spectrometers for condensed matter studies at the IBR-2M reactor Anatoly M. BalagurovFrank Laboratory of Neutron Physics, JINR, Dubna, Russia • Neutron scattering for condensed matter science. • IBR-2M pulsed reactor as a neutron source of third generation. • Performance of neutron scattering spectrometers at the IBR-2M. • Perspectives. Hydrogen: primary energy sources, energy converters and applications

  2. Neutron space and time domain S(Q, ω) ~ ∫∫ei(Qr – ωt) G(r, t)drdt l ~ 2π/Q, τ~ 2π/ω For elastic scattering: ΔQ = (10-3 – 50) Å-1 Δl = (0.1 – 6·103) Å Nanostructured materials are inside! • Neutron scattering features: • Strong magnetic interaction, • Sensitivity to light atoms, • Sensitivity to isotopes, • Large penetration length, …

  3. Success of neutron scattering experiment depends on: I. Parameters of a neutron source average power, pulse width, spectral distribution, ... II. Performance of a spectrometer intensity, resolution, (Q, E)-range, available sample environment,... III. Team at spectrometer head of team, experience,contacts,...

  4. Neutron sources for condensed matter studies I. Continuous neutron sources II. Pulsed neutron sources W = 10 – 100 MW Const in time II-a. SPS II-b. LPS VVR-M, Russia IR-8, Russia, ILL, France LLB, France BENSC, Germany FRM II, Germany BNC, Hungary NIST, USA ORNL, USA … SINQ, Switzerland W = 0.01 – 1 MW Pulsed in time Δt0≈ (15 – 100) μs W = 2 – 5 MW Pulsed in time Δt0≈ (300 – 1000) μs ISIS, UK LANSCE, USA SNS, USA KENS, Japan J-SNS, Japan IBR-2M, Russia ESS, Europe LANSCE (new) ???

  5. Fermi chopper with 2 slit packages 21.79 m 22.5 m 23.5 m 29.9 m 6 Disc choppers 49.6 m 73.4 m Magnet (25 T) TOF high-resolution diffractometer at LPS type source Neutron pulse after fast chopper Δt0≈ (20 – 50) μs Δd/d≈ 0.001 for back scattering

  6. HRFD – High Resolution Fourier Diffractometer at IBR-2 Put into operation in 1994 in collaboration between: FLNP (Dubna), PNPI (Gatchina), VTT (Espoo), IzfP (Drezden)

  7. HRFD resolution The utmost TOF resolution of HRFD For V=11,000 rpm & L=30 m Rt=0.0002 (0.0009 now) Diffraction patterns of Al2O3 measured at ISIS (UK) and IBR-2 (Dubna). Resolution is the same, despite L is 5 times longer at ISIS.

  8. Neutron spectrometers on the IBR-2M reactor Diffraction (6): HRFD, DN-2, SKAT, EPSILON, FSD, DN-6 SANS (2): YuMO,SANS-C Reflectometry (3): REMUR, REFLEX,GRAINS Inelastic scattering (2): NERA, DIN 13 spectrometers (3 new)

  9. Spectrometers on existing pulsed neutron sources* * At a new SNS (Oak Ridge) neutron source 18 spectrometers are planning ** Numbers in brackets – spectrometers at the II Target Station *** IPNS is closed in the very beginning of January 2008

  10. Diffraction at the IBR-2M • HRFD* powders – atomic and magnetic structure • FSD* bulk samples – internal stresses • DN-2powders – real-time, in situ • DN-6 microsamples – high-pressure (new project) • EPSILON** rocks – internal stresses • SKAT** rocks – textures * Fourier RTOF technique ** Long (~100 m) flight pass

  11. Diffraction at the IBR-2M. Resolution. HRFD powders FSD internal stresses DN-2real-time, multilayers DN-6 high-pressure EPSILON stresses SCAT textures Resolution becomes better for longer d-spacing!

  12. 1 2 No 1 No4 4 • Chamber of the cold moderator. • Light water pre-moderator. • Flat water reflector. • Outer border of the reactor jacket. 20K No 5 300K No 6 water 3 No 9 Combi-moderator at the central direction of the IBR-2M reactor, plan view

  13. Cold moderators at the IBR-2M reactor Gain factor as a function of λ Diffraction patterns of TbFeO3 measured at Tmod=30 K and 300 K Neutron flux distributions as a function of λ

  14. HRFD development Actual state Resolution: one of the bestin the world Intensity: not high enough (Ωd≈0.2 sr) • Neutron guide • Detector array • Correlation electronics Could be Resolution: best among neutron diffractometers Intensity: 10 times better than now ~500 KUSD

  15. New diffractometer for micro-samples and high-pressure studies Chopper Neutron guide Sample Actual state Ring-shape detectors Ring-shape multi-element ZnS(Ag)/6LiF detector Resolution: optimal for high-pressure studies Intensity: one of the best in the world Pressure: up to 7 GPa in sapphire anvils • Detector array • Neutron guide Could be Intensity: 25 times better than now Pressure: 20-30 GPa in natural diamond or mussonite ~250 KUSD

  16. GRAINS: complete reflectometry at the IBR-2M reactor FLNP: M. Avdeev, V. Lauter-Pasyuk Germany: H. Lauter V. Aksenov, V. Bodnarchuk PNPI: V. Trounov, V. Ul’yanov Parameters: Resolution: optimal, δλ/λ = (0.3 – 7)%, angular = (1 – 10)% Q-range: optimal, (0.002 – 0.3) Å–1 Intensity: one of the best in the world Modes: Cost estimate = 1050 kEUR Contributions: - Germany, Hungary, - Romania, external. • Reflectometry in vertical plane, • Off-specular scattering, • GISANS with polarized neutrons.

  17. A new reflectometer GRAINS at the IBR-2M reactor Main feature: vertical scattering plane→ studies of liquid media

  18. Frank Laboratory of Neutron Physics Condensed Matter Department Proposals for IBR-2M spectrometer complex development program Editors: Victor L. Aksenov, Anatoly M. Balagurov Dubna, 2006 The second edition of the proposals is under preparation.

  19. Proposalsfor 2008 – 2011 Development of existing spectrometers New spectrometers General-purpose projects • HRFD (SA) • FSD (SA) • DN-2 • SKAT (BMBF) • EPSILON (BMBF) • YuMO • REMUR • DIN (RosAtom) • NERA (Poland) • Moderators • Detectors • Sample environment • Cryogenics • Electronics • DN-6 • RTS • SANS-C • GRAINS • SESANS • SANS-P 2,700 K$ 3,000 K$ 4,000 K$ In total: 9.7 M$ for4years

  20. Priorities for 2008 Priorities for 2009 - 2011 Approved projects Strategical necessity YuMO / SANS-C FSD DN-6 Projects with external support Projects without clear perspective REMUR, NERA, DIN, SESANS, SANS-P, DN-2, RTS SCAT EPSILON GRAINS HRFD

  21. New science after 2010 Modern material science - nanostructures (catalysts, multilayers, porous materials, …), - materials for energy (electrochemistry, hydrogen, …), - biomaterials, polymers (soft-matter), - new constructive materials for atomic energy, - geological problems (earthquakes, waste deposit, …), … Modern fundamental physics - complex magnetic oxides with strong correlations, - low-dimensional magnetism, - phase coexistence in crystals, …

  22. User program at the IBR-2 spectrometers International experts’ commissions: Time-sharing (13 spectrometers) FLNP (35%) I. Diffraction II. Inelastic Scattering III. Polarized neutrons IV. SANS External fast (10%) External regular (55%) User statistics IBR-2 operational time: ~2000 hours/year Number of experiments: ~150 per year External users: ~100 per year Others, 19% FLNP, 25% France, 3% Poland, 5% Germany, 17% Russia, 31%

  23. Condensed Matter Department at FLNP JINR staff38 Member States staff 28 Professor 4 Doctor of science 10 Candidate of science 26 Ph.D. + students 11 1999: 52 + 28 = 80 2007: 38 + 28 = 66 What staff do we need? CMD administration ~ 4 Heads of directions 4 Group at spectrometer ~ 3x13 = 39 Technical group 5 Additional techniques ~ 5 Scientific groups ~ 10 ~ 67 Age distribution There exists a substantial deficiency of permanent staff personnel

  24. IBR-2 is one of the best neutron sources in the world and the only existing advanced neutron source among JINR Member States. • Existing spectrometers are comparable with that at other advanced pulsed neutron sources; some of them are unique. • Experimental potential of the complex is much higher than that existing now. • All spectrometers are accessible for international community in a frame of accepted proposals. • Period 2008 – 2010 is most convenient for global development of neutron spectrometers. • Adequate financial support is urgently needed.

  25. Ambitious goal for Condensed Mater Department, Frank Laboratory of Neutron Physics, and Joint Institute for Nuclear Research: Experimental complex based on the IBR-2M reactor for fundamental and applied investigations of advanced and nanostructured materials.

  26. From White-Egelstaff law-book for thermal neutron scattering (~1970): Law 2: Neutrons are to be avoided where there is an alternative! New version: Neutrons can be applied everywhere, even if an alternative there exists! For studies of nanostructured materials as well !

  27. Thank you !

  28. Neutron spectrometers on the ISIS spallation source (RAL, UK) Diffraction (8): GEM, HRPD, PEARL, POLARIS, ROTAX, SXD, ENGIN-X, INES SANS (2): SANDALS, LOQ Reflectometry (2): CRISP, SURF Inelastic scattering (9): HET, MAPS, MARI, MERLIN, PRISMA, IRIS, OSIRIS, TOSCA, VESUVIO 21 spectrometers

  29. from MEETING REPORT “Consultancy on the Status of Pulse Reactors and Critical Assemblies” IAEA, 16 – 18 January 2008 The IBR-2 reactor at Joint Institute on Nuclear Research, Dubna is a unique facility internationally, and is being refurbished/modernized to continue to serve as an international centre of excellence for neutron sciences.

  30. Diffraction at the IBR-2M. Intensity. Mo powder measured in 1 min (1) and 0.2 sec (2). Intensity / Counting rate I ≈ Φ0 · S · Ω/4π · δ [n/s] ≥ 106 n/s Φ0 – neutron flux at a sample, 107 n/cm2/s S – sample area, 5 cm2 Ω – detector solid angle, 0.2 sr δ – scattering probability, 0.1

  31. IBR-2M pulsed reactor (with cold moderators) is the source of third generation*) *) For 2nd generation sources W is between 6 – 200 kW (IPNS, KENS, LANSCE, ISIS)

  32. Resources which are needed to complete the 2007 - 2010 program Technical needs: 1. Neutron guides – ~300 m 2. 1D PSD – 5 3. 2D PSD – 4 4. Large aperture det-s – 6 5. Choppers – 6 6. Neutron optics devices 7. Spin analyzers & polarizers 8. Electronics & computing 9. Sample environment: refrigerators, thermostats, magnets, acoustic technique… Financial needs (in KUSD): A. Development (9) – 4,105 (456) B. New projects (6) – 2,991 (499) Total (15): 7,096

  33. Hydrogen materials: what can we learn with neutrons? Location of H, OH, H2O in crystal: coherent elastic, diffraction. Dynamics of H, OH in crystal: incoherent inelastic. Diffusion of H, H2O in solids or liquids: quasielastic incoherent. Clustering of H, nanostructures: coherent elastic, SANS. Exchange membrane, hydration/dehydration: diffraction, reflectometry. Quantitative analysis: incoherent scattering/ absorption. H (and Li) are the most important Elements for fuel cells and batteries! Proton exchange membrane

  34. Phase transformations of high pressure heavy ice VIII. Time-resolved experiment witht = (1 – 5) min. Ih Ice VIII Ic hda Time & temperature scale TOF scale Time / temperature scale: Tstart=94 K, Tend=275 K. The heating rate is ≈1 deg/min. Diffraction patterns have been measured each 5 min. Phase VIII is transformed into high density amorphous phase hda, then into cubic phase Ic, and then into hexagonal ice Ih.

  35. Project EPSILON/SKAT: Investigation of strain/stress and texture on geological samples Spokesman from JINR: Dr. Ch. ScheffzükSpokesman from Germany: Dr. habil. A. Frischbutter EPSILON-MDS SKAT New neutron guide Could be ~106 EUR Intensity: 10 times better than now

  36. Diffraction at the IBR-2M. General conclusion. Unique complex with world top opportunities in: - extremely high-resolution (HRFD), - extremely high-intensity (DN-6, DN-2), - applied studies (FSD, EPSILON, SKAT).

  37. Polarized neutron scattering at the IBR-2M • REMUR magnetic multilayers – magnetic structures • 2. GRAINS interface science in physics, biology, chemistry • (new project) • 3. REFLEX reflectometry in horizontal plane, • now is used in test mode

  38. Resolution at pulse neutron source. Elastic scattering. R = [(Δt0/t)2 + (Δ/tg)2]1/2 For Δt0 ≈ 350 μs, L ≈ 25 m, λ≈ 4 Å TOF contribution is ~1%. Geometrical contribution is: ~(0.05 – 0.2)% for back scattering ~(5 – 10)% for SANS and reflectometry TOF component in resolution function is not important for: SANS and Reflectometry It is not very important for: single crystal diffraction, magnetic diffraction… Powder diffraction: structural studies, stress analysis, low symmetry textures?

  39. Criteria which could be used for the evaluation Modern and interesting science. Correspondence to the IBR-2M features. Top level parameters. Active and effective team. External support (financial, technical, …).

  40. Proposals at the IBR-2 reactor, JINR, Dubna IBR-2 operational time: ~2000 hours/year Number of experiments: ~150 per year External users: ~100 per year

  41. Research reactors in the JINR Member States Russia Czechia I. Dubna, IBR-2 (1984, 2 MW, pulsed) II. “RCC KI” Moscow, IR-8 (1957, 8 MW) III. Gatchina, VVR-M (1959, 16 MW) IV. Yekaterinburg, IVV-2M (1966, 15 MW) V. Obninsk, VVR-M (1960, 12 MW) I. Řeź, LVR-15 (1970, 10 MW) Germany I. Munich, FRM-II (2005, 20 MW) II. Berlin, BENSC (1973, 10 MW) Hungary I. Budapest, BNC (1970, 10 MW) The enhanced flux and new instrument concepts will allow to improve the resolution in both space and time ==> “new science”!

  42. Neutron Techniques (developed at the IBR-2) DINS Deep Inelastic Neutron Scattering INS Inelastic Neutron Scattering LND Laue Neutron Diffraction NBS Neutron Back-Scattering ND Neutron Diffraction NHol Neutron Holography NI Neutron Interferometry NPol Neutron Polarimetry NRad Neutron Radiography NRef Neutron Reflectometry NTom Neutron Tomography NSE Neutron Spin-Echo PolN Polarized Neutrons PST Phase-Space Transformation QENS Quasi-Elastic Neutron Scattering SANS Small Angle Neutron Scattering TAS Triple-Axis Spectrometry TOF Time-Of-Flight (techniques) USANS Ultra SANS ZFNSE Zero-Field NSE At the IBR-2 the techniques are developed, which are the most effective for condensed matter studies and above all for studies of nano-structured materials.

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