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Experimental Devices

Isochronous cyclotron U-120M

 

Isochronous Cyclotron U-120M is a basic experimental facility of the NPI. Current parameters of accelerated and extracted beams are: p+/ H: 5.4–38 MeV, D+/ D: 11–20.5 MeV, 3He+2: 16.2–55 MeV, 4He+2: 22–40 MeV. External beams extracted from negative regimes by the stripping method can reach tens of μA while the beams extracted from positive ones by the deflection system are at the level of a few μA.

The cyclotron is routinely operated both in positive and negative modes. Due to this unique layout, the cyclotron can deliver ion beams (including 3He2+ ions, currently rarely available on cyclotrons) with very well defined optical parameters (low emittance, low energy dispersion dE/E ~ 5.10−4) for nuclear physics experiments in basic research (i.e. astrophysics, nuclear data measurements etc.) and also high intensity beams for applied research (i.e. generation of fast neutron fields, production of radionuclides for research and development of new radiopharmaceuticals etc.).

In comparison with commercially available cyclotrons, the U-120M is versatile machine tunable in a wide energy range and usable in a broad spectrum of research and application programs. Moreover, the cyclotron is operated by specialists with a long-term experience in acceleration technique who are able to provide routine service as well as complex machine upgrades including operation and development of various types of target stations.

 

Cyclotron-based fast neutron facility

 

The high-power proton and deuteron beams from U-120M cyclotron are employed for generation of fast neutron fluxes. Versatile irradiation stations are designed using different neutron source targets (solid, liquid and gaseous samples).

Among them, the flowing heavy water was investigated and employed for the first time as neutron source target. The high-power white-spectrum neutron flux extending to 35 MeV from the p-D2O reaction is routinely operated. The small-size samples (diameter of 15 mm) could be irradiated at neutron flux up to 1011 n/cm2/s at this station. The spectral flux in the energy range of 2-35 MeV and its variance with source-to-target distance are well determined using the scintillator technique and activation-foils method backed by the MCNPX calculations. The 7Li(p,n) reaction induced by 20-37 MeV proton beam is used for the production of quasi-monoenergetic neutron field. The scintillator pulse-height unfolding technique based on the n-gamma discrimination hardware and many-parameter data-acquisition system allows neutron spectrometry in the energy range from 0.7 to 35 MeV. The gamma activities of irradiated samples are investigated using gamma-spectrometry sets based on the High-Purity Germanium detectors, relevant spectrometry electronics and data analysis software.

At present the system of fast neutron generators is the only facility in EU countries which is able to simulate neutron fields of future tester of radiation hardness of fusion related materials (IFMIF, International Fusion Materials Irradiation Facility).

 

Tandetron accelerator

 

The accelerator Tandetron 4130 MC, put into operation in 2005, is a source of accelerated ions of most of elements from H to Au with energies from 0.4-20 MeV and intensities up to tens of mA. The main laboratory accessories are devices for material characterization by standard nuclear analytical techniques (RBS, RBS-channeling, ERDA, ERDA-TOF, PIXE, PIGE, and Ion-Microprobe with 1 mm lateral resolution) and for high-energy implantation. In the laboratory there are several other devices intended mostly for preparation of micro- and nano-structures using different deposition techniques and for their characterization by other complementary methods (e.g. AFM). Staff qualification and the parameters of the experimental devices of the laboratory are fully comparable to similar ones worldwide. With this equipment the laboratory is unique in the Czech Republic and it is able to meet all specific demands of Czech and foreign research organizations.

 

Neutron diffraction and scattering facilities

 

Facilities installed on neutron channels of the nuclear reactor LWR-15 operated by Nuclear Research Institute Řež:

  • Double axis diffractometer SPN-100 for residual strain/stress mapping and neutron radiography and topography experiments.
  • Powder diffractometer MEREDIT for structure studies of polycrystalline materials equipped with a cryostat, high temperature furnace and tension/compression rig permitting high quality experiments on samples under different external conditions.
  • Multipurpose double-axis diffractometer (MDAD) for Bragg diffraction optics studies, ultrahigh resolution diffraction experiments and for texture analysis of materials of technological interest.
  • Double-bent-crystal diffractometer for high-resolution small-angle scattering, MAUD, is equipped with a linear position-sensitive detector, tension/compression rig and a high temperature furnace, suitable for investigations of condensed matter microstructure in the size range 50 – 3000 nm.
  • Double axis diffractometer TKSN-400 for in-situ investigation of polycrystalline materials under thermomechanical loads and testing new neutron optical techniques.

MEREDIT and MAUD are new and were constructed and installed in the years 2007-2009. MEREDIT is equipped with modern multidetector and changeable monochromator systems. MAUD employs ultrahigh resolution multiple reflection monochromator, our recent invention, and opens new area of experiments. MAUD is one of two such instruments in the world optimized for momentum transfers just between the ranges of the classical collimator systems and the ultrahigh resolution Bonse-Hart cameras. SPN-100 and TKSN-400 are continuously modernized.

 

Other important equipment

 

  • Radiochemical laboratories for activation analyses have been reconstructed recently.
  • Radiopharmaceutical laboratories have been constructed during last 15 years.
  • Microtron BMT 25 – electron accelerator with energy from 6 to 24 MeV and current up to 25 mA used mainly for photon activation analysis has been modernized.
  • ESA12 – high resolution electrostatic spectrometer for 0÷8 keV electrons, suits well for the basic tests of electron sources developed for the KATRIN project, but should be recovered in reasonable pace.
  • SEIKO PRECISION HSP-1000 Digital Imaging Microscope purchased in 2009, used for analysis of nuclear track detectors,  at present unique in Europe.
  • Two low background liquid scintillation spectrometers Quantulus 1220 acquired in 2001 and 2009 serve for 14C activity measurement in environmental samples and radiocarbon dating.
  • Last update
    Friday, 25 May 2012
  • Thursday, 16 September 2010
  • Autor
    Jan Weinhold