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Instruments – Ineleastic Tuesday 9 July 2013, Fintry Room, 14:30-16:30 Instruments – Ineleastic (invited) Status report of the J-PARC MLF (The J-PARC Materials & Life Science Experimental Facility) M Arai J-PARC Materials & Life Science Experimental Facility, Japan J-PARC MLF was designed to be a 1 MW spallation neutron source. Presently the power of the proton accelerator is 300 kW with a very stable operation at 94%, a world-class stability, after recovering in January 2012 from the damages by the devastating disaster happened in March 2011. In order to mitigate the pitting on the Hg-target container, now we are injecting helium micro bubbles in the target. The Laser Doppler vibrometory from the container showed us that vibration on the proton bombardment has obviously reduced by the injection. 20 instruments have been already funded, 16 are operated for user program and four instruments are under either commissioning or construction. Operational time for user program in JFY2012 was about 180 days, and we have received more than 550 experimental proposals from users. We have introduced innovative instrument design, such as multi-Ei measurement, pulse-shaping chopper with coupled moderator, intensive background suppression design, event-recording data acquisition etc. Instruments perform quite well at world class and users are very much enjoying experiments even at 300kW. World-class scientific outputs have been already created in various scientific fields, ranging from Li-battery science to bio-molecular science. Since J-PARC is internationally open for users, we have got experimental proposals from abroad more than 10% of the whole proposals. More than 30% of proposals have come from industries, such as Toyota, Nissan, Honda, Panasonic and other big industries. This fact has revealed a new horizon has come in the neutron scattering science in the 21 century. We are expecting those statistics will be increased more than three times at 1MW in three years’ time. So how well does LET perform? R Bewley, J Taylor, T Guidi, R Stewart and V Garcia ISIS, UK LET is a cold neutron direct geometry spectrometer which resides within the new second target station at the ISIS facility. It has been optimized to take advantage of the high fluxes of cold neutrons this target station was designed for. Features include a wide dynamic range with large neutron fluxes over incident energies from 0.5-30 meV and excellent energy resolutions of up to 8 μeV are possible. The detector array will consist of a massive π Steradians of position sensitive He3 tubes. At present the detector array is still being populated. To enable virtually gapless detector coverage the detectors are the worlds longest at 4m long. The instrument was also designed to take extreme sample environment, with the most popular piece by far being the 9T wide opening magnet with dilution fridge. To make use of the long 100ms time frame LET runs in multi repetition rate mode with typically around 5 incident energies per frame covering the full dynamic range. We are presently installing polarization equipment which will enable XYZ polarization within the next year. LET has run user experiments for around 18 months now and in this talk I will discuss the performance of LET over this period including ‘the good, the bad and the ugly’. ICNS 2013 International Conference on Neutron Scattering DC-TOF : A new time-of-flight neutron spectrometer J-Y So and E Kim Korea Atomic Energy Research Institute, South Korea The Disk Chopper Time-of-Flight Spectrometer (DC-ToF) is a new neutron time-of-flight spectrometer at HANARO cold neutron research facility(CNRF). It uses multi disk chopper cascade, elliptical shape focusing guide and array of long 3He position sensitive detectors (PSDs). The DC-ToF has been developed since 2003 and the first time-of- flight spectra were measured in March 2012. Since then, the commissioning of the DC-ToF has been taken, and it will be open for users from the August. In spite of the small number of PSDs, we can measure scientific data of hydrogen storage materials such as metal-organic-framework (MOF) and zeolite-imidazolate-framework (ZIF). In this presentation, we would describe the instrumental characteristics and performance, and the result of standard sample and others. Pelican: An inelastic neutron scattering spectrometer with polarization analysis R Mole and D Yu Bragg Institute, ANSTO, Australia A new cold neutron time-of-flight inelastic neutron scattering instrument, Pelican, is currently being commissioned at the OPAL research reactor at ANSTO. The instrument is constructed to be of broad use with applications ranging from condensed matter physics, through to polymer science and soft condensed matter. The use of large PSD detectors, gives approximately 0.8 steradian coverage, thus a large fraction of reciprocal space can measured simultaneously, allowing the study of single crystals as well as powders and liquids. Polarization analysis has been implemented using a supermirror bender for polarization, while analysis will utilize Pastis coils and a wide angle 3He cell. The inclusion of polarization analysis further extends the potential use of Pelican to include the study of purely magnetic excitations over a large fraction of reciprocal space. In this contribution I will present the scientific background behind the instrument along with initial results from the commissioning experiments. First 100 days of commissioning of the new backscattering spectrometer IN16B B Frick, D Bazzoli and T Seydel Institut Laue-Langevin, France The new cold neutron backscattering spectrometer IN16B at ILL enters the commissioning phase. Designed and optimised for high count rate, high energy resolution and high momentum transfer[1], it uses Si(111) -1 monochromator and analysers in perfect backscattering with an energy resolution below 1 µeV and a Qmax ~ 1.9 Å . IN16B is located at the end of a ballistic neutron guide delivering neutrons to a 12% velocity selector, followed by an elliptical focus guide feeding the phase space transformation (PST) chopper. Recent measurements confirm the simulated flux[2]. The PST concentrates the intensity into a narrow energy band but increases divergence. A large spherical perfect crystal monochromator [3] mounted in backscattering on a Doppler drive allows for doubling the energy transfer range compared to IN16. The secondary spectrometer and neutron flight path is evacuated as a measure to lower the background, like the possibility to run a background chopper in phase with the PST [3] or the side position option where a PG(002) deflector narrows further the incident wavelength band. A doubling of the analyser solid angle compared to IN16 is foreseen by nearly 3m high analysers - of which a first prototype might just be tested- a new vertically sensitive PSD and increased cryostat tails. The instrument layout allows for the ICNS 2013 International Conference on Neutron Scattering implementation of additional options such as Si(311) and GaAs(002) and an inverted time-of-flight setup, BATS [4,5]. [1] Frick, B.et al. Physica B, 385-86 (2006) 1101 [2] H.N. Bordallo et al.; Journal of Neutron Research 16 (2008) 39 [3] Hennig, M.,et al.; Journal of Applied Crystallography, 44 (2011) 467 [4] van Eijck, L. et al; NIM A, 672 (2012) 64. [5] A. Magerl et al, BMBF proposal A comparison of the direct geometry spectrometers at the spallation neutron source M Stone, G Granroth, G Ehlers and B Winn Oak Ridge National Laboratory, USA There are currently four direct geometry spectrometers at the spallation neutron source: ARCS, CNCS, HYSPEC, and SEQUOIA. These four instruments offer a range of measurement capabilities throughout energy transfer and momentum transfer space. There also exists a range of incident energies where these instruments overlap in their capabilities. To characterize this range, we have measured an identical sample using each of these instruments. I will present these data to compare the capabilities of these four instruments. I will also present a description of the capabilities of these instruments including highlights of their research accomplishments. IN1-LAGRANGE on the hot neutron source at ILL: New sensitive spectrometer for high-resolution studies of vibration dynamics in complex materials A Ivanov1, J Kulda2, M Jimenez-Ruiz2 and S Fuard2 1Institut Laue-Langevin, France, 2Institut Max von Laue – Paul Langevin, France IN1-LAGRANGE is dedicated to studies of high-energy excitations, such as molecular vibrations, in different classes of complex materials available as a rule in non-oriented forms (polycrystals, powders, glasses, composites, biological matter etc.). The instrument design is based on the space focusing of the neutrons scattered by the sample in a very large solid angle and then registered by a relatively small single counter. The analyzer is built from appropriately oriented pyrolytic graphite crystals set to reflect neutrons with a fixed central energy of 4.5 meV. The subtended solid angle is as high as ~2.5 Steradian with characteristic analyzer dimensions less than 1 meter. A cooled beryllium filter is put in the neutron scattering path in order to suppress higher-order reflections by the analyzer crystals. The new instrument demonstrates a very high sensitivity such that vibration spectra of samples with sub-milligram hydrogen content can be measured on a time scale of several hours. It is important that the use of single crystal reflection in the analyzer in combination with the reduced collimation of the incident monochromatic beam will permit experiments with relative energy resolution down to ~1%. The resolution/intensity optimization can be comfortably performed in a broad range with typical time for changing over from one instrument setting to another less than an hour. The secondary spectrometer LAGRANGE (LArge GRaphite ANalyzer for Genuine Excitations) fully benefits from the completed upgrade of the IN1 crystal monochromator with several double- focusing reflecting planes and the available incident neutron energies in the range ~ 5 - 1000 meV.
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