Polarized or unpolarized neutron reflectometry.

Prompt Gamma Activation Analysis (PGAA) is located at the end of the cold neutron beam No. 1 at Budapest Research Reactor (upper subbeam). Neutrons irradiate samples in a chamber equipped with an automated sample changer. Here the neutron flux is 1.2 E8 n/cm2/s. The emitted gamma radiation is detected using a Compton-suppressed HPGe detector. The elemental composition of the samples are then detected based on the prompt gamma spectra. Both neutrons and high-energy gammas penetrate into material deep, so the analysis gives the average composition of the irradiated sample volume. The method can be used for a non-destructive analysis of a large variety of samples. In principle all chemical elements can be analysed using the method, however it is mainly used in the analyses of light elements, especially hydrogen and boron. With PGAA, closed containers even operating chemical reactors can be investigated.

Small Angle Neutron Scattering (SANS) is a powerful tool for the structure determination of materials on nanometer scale (5 - 1400 Å). Among the advantages of using SANS one can mention that it is a non destructive method, sensitive to different kinds of isotopes and to the magnetic structure, and it gives information from the whole illuminated volume of the material. The SANS instrument named Yellow Submarine covers the momentum transfer range: 0.003 - 0.5 Å^-1. The neutron beam is monochromatized by a neutron velocity selector allowing to change the wavelength between 3 - 25 Å. The wavelength resolution is between 12-30%. The automatic sample changer having 6 positions can be thermostated from an external bath between -10 and 150 C. The sample to detector distance can be varied between 1.3 - 5.5 m. The scattered neutrons are detected by a two dimensional position sensitive BF3 detector having 64x64 pixels of 1x1cm^2 size. The neutron flux at the sample position is: 5*10^7 n/cm2s.

Neutron, gamma and X-ray radiography is an advanced technique for Non-Destructive Testing. It makes it possible to visualize the inner structure and medium speed movements inside the investigated objects. The unique feature of our radiography station the complementer inspections of the large objects as helicopter rotor blades (10m X 0,7m; 200kg) in Europe.

The Budapest Research Reactor is a tank type, light water moderated and cooled, Russian (Soviet) type research reactor. It became critically in 1959. BRR had two major reconstructions; at the first one the reactor power was increased from 2 to 10 MW, while the second one was a full scale reconstruction (1986-1992), all construction parts were replaced and several safety innovations were introduced. From 1993 the average yearly operation time is 3500 hours. BRR as a high flux neutron source has been utilized for basic and applied research and it has satisfied real research demand. The cold neutron source installed in 2000 significantly extends the scientific use of the research reactor. Currently, 14 neutron facilities are operated around the research reactor. The Budapest Neutron Centre was founded to enhance the scientific use of the BRR.

The goal of the neutron induced prompt-gamma spectrometry (NIPS) station is to provide cold neutrons for a wide variety of experimental setups for studying neutron-induced radiations in samples. The possible setups include nuclear physics experiments with many detectors and analytical experiments that require unique geometries. For example, we have constructed setups for 3D prompt-gamma imaging (PGAI) and for neutron tomography (NT). Processes in In-situ catalytic reactor can be followed by prompt-gamma analysis to measure the quantity of uptake of catalyst. The NIPS experimental station is at the end of guide No. 1 in the Guide Hall of the Budapest Research Reactor. Concrete biological shielding surrounds the super mirror neutron guides. The neutron beam is divided into two parts; the upper feeds the PGAA station and the lower serves the NIPS station. The Al flight tube is inlined with 6Li-enriched polymer, which absorbs the scattered neutrons. The sample position is 2.5 m from the end of the neutron guide. The flux of the 2x2 cm collimated beam is 3x10^7 n/cm^2/s.

The BAGIRA irradiation rig, along with the materials testing laboratory, is part of the Budapest Research Reactor. The device is used for study the radiation damage caused by high energy neutron radiation in structural materials. The temperature can be controlled in the vertical irradiation channel, with a neutron flux permitting the accelerated testing of pressure vessel materials of nuclear reactors. The samples can be investigated in the mechanical laboratory.

The neutron activation analysis (NAA) is a non-destructive, multi-element analytical method, which can be applied for environmental chemistry, geochemistry, biological and medical research. NAA still preserves its role in the large amount analytical methods, due to excellent selectivity and high sensitivity (for about 75 elements less than 0.01 μg can be determined). The majority of the NAA investigations are based on the determination of short-life isotopes. The pneumatic sample transfer system (rabbit system) ensures the sample transfer to the irradiation position in the reactor core. The neutron activation analysis is always combined with computerized high resolution gamma-ray spectrometry.

The cold triple axis spectrometer is able to measure inelastic excitattions in (q,e) range (0-2.7A^-1 , 0 5meV ( with characteristic resolution of 120-150 microeV The main parameters of the spectrometer : Monochromator : pyrolitic graphite 90x80 mm (24min) Analyser : pyrolitic graphite 50x90 mm (24min ), or Ge monocrystal (15min mosaicity) Collimations : interchangeable 45', 30', 15' Range of monochromator angle: 342th 126deg Range of scattering angle : -120 2th 70 Range of analyser angle : -40 2th 120 Range of crystal orientation : 0 2 360 Angular resolution : 0.01 deg Flux at specimen : 2x10^6 n/cm2/.sec Beam size : 25x90 mm2 Momentum transfer : 0 - 2.7 Å-1 Energy transfer : 0 - 9 meV Characteristic resolution at 3.3 Å 120-150 microeV Sample enviroment : cryostat (liq. N2) , magnet up to.2T, max scattering angle 100 deg furnace up to 1000C, Thermostate (-20C-100C).

MTEST a multifunction neutron diffractometer has been installed at the 6. axial thermal channel of the Budapest Research Reactor. Although it is optimised for strain determination of structural materials but following the easy mounting of its parts it is suitable for atomic structur investigations in crystalline and amorphous state as well. Using different monochromarors the neutron wavelength can be changed in the range of 0.065-0.35 nm. The collimated then on the sample scattered neutrons are detected by a BF3 single detector in 0°-144° scattering angle range. For special needs a vacuum-furnace (RT-1000ºC) can also be placed on the sample table.

The exposure faciliy constructed at the 5th horizontal channel of the Budapest Research Reactor is capable to utilize the mixed neutron and gamma radiation. The neutron flux, dosis and the neutron-to-gamma ratio can be varied in several order of magnitude.

GINA is a fix (3,20, 3,97, 4.65 or 5,24 Ǻ) wavelength, vertical-sample, "Tanzboden"-type polarized neutron reflectometer installed on the 10/3 guide of the Budapest Neutron Center with a 5-element focussing pyrolytic graphite monochromator, slit system, cryo-cooled Be-filter, two-dimensional delay-line-type He-3 detector, single supermirror analyzer and polarizer as well as a 0,5 T electormagnet and a 20-300 K closed-cycle He-cryostat option. Latter to be optionally combined with the magnet option.

The 'PSD' neutron diffractometer has been installed at the No. 9 tangential, thermal channel of the Budapest Research Reactor. The PSD neutron diffractometer is suitable for atomic structure investigations of amorphous materials, liquids and crystalline materials, if the resolution requirement is not high. The monochromised and collimated neutron beam is scattered on the investigated specimen, and the scattered diffractogram is detected by a linear position sensitive detector system. The detector assembly is mounted on the diffractometer arm and it spans a scattering angle range of 25° at a given detector position. The entire diffraction spectrum can be measured in five steps.

FSANS - Focusing Small Angle Neutron Scattering Spectrometer. Operates on a cold neutron beam of the Budapest Research Reactor. Monochromation by rotating velocity selector. Wavelenght range: 3.5 - 20 Å. Collimation options: multichannel converging collimator - maximum sample diameter: 25 mm; true ellipsoidal supermirror - maximum sample diameter: 60 mm. 2D position sensitive detector, 200 x 200 mm2 active area. Best resolution: 4E-4 Å-1. Q-range: 8E-4 - 1.2 Å-1, the high limit available with rotated detector arm.

Atomic resolution hologrraphic instrument and thermal three-axes spectrometer for neutron holography experiments, inelastic neutron scattering experiments and hy resolution transmission measurements. The instrument is installed at the 8th thermal neutron beam of the Budapest Research Reactor.

The new instrument TOF installed to a radial thermal neutron beam in a new guide-hall at BNC is the one of the highest resolution operating neutron diffractometer at the present time. The time-of-flight monochromator system consists of a fast double and two single choppers and a straight neutron guide with 2.5x10 cm cross section at the end. The double chopper is designed for a maximum speed of 12000 rpm. While in high resolution mode the very short - 10µs - neutron pulse and the 25m total flight path allows us to obtain a diffractogram with 10-3Å precision (at back scattering) in a single measurement, in low resolution mode liquid diffraction can be performed at good neutron intensity up to 15Å-1 scattering vector. The resolution of the instrument allows to study the fine structure of crystalline materials. After desired upgrades it will be applicable for inelastic neutron scattering experiments too.

REF - neutron reflectometer. This instrument is mainly used for neutron optical research. Operates on a cold neutron beam of Budapest Research Reactor. The instrument works at constant wavelength, 4.28 Angstrom. The monochromatization is provided by two PG monochromator. The collimator system- two Cd slits- gives 10-3 rad collimation. The sample can be rotated with accuracy 0.005 degree. The reflected beam is detected by a 200x200 mm2 position sensitive detector.