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centered on nuclear Bragg positions. Polarized neutron scattering data taken on a single crystal of Ho 2 Ti 2 O 7 using D7 are shown in the figure. In unpolarized data (C), the pinch points are not visible,

inelastic scattering. In the example shown here, D7 was used to measure the magnetic spectra from a Tb 2 Sn 2 O 7 magnetic pyrochlore. The compound has magnetic frustration, but it does partially order if the

neutrons: polarized neutrons: flux at sample ~3.6 10 6 n/cm 2 /s at λ = 1.3 Å (Cu 200) ~7.1 10 6 n/cm 2 /s at λ = 2.4 Å (PG 002) ~ 2.10 6 n/cm 2 /s at λ = 1.3 Å (PG 002 + Heusler 111) typical sample size ... change automatically the incoming neutron wavelength in the range 1 - 3 Å (unpolarized neutrons) and 1.2 - 2.4 Å (polarized neutrons). The ...

distances / m 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11.2, 14.4, 17.6, variable apertures at 19.1 Sample area maximum flux at sample (for Δλ/λ = 10%) 1.2x10 8 n cm -2 s -1 typical sample size 10 to 300 mm 2 Detector distances ... distances 1.1 ... 17.6 m rotation -2° < 2Θ <22° horizontal offset -5 ... 50 cm area 102.4 x 98 cm 2 pixel size 8 x 8 mm 2 maximum ...

/ T1/2 λ(293 K) = 0.147 nm Electric charge q n = - (1.5 ± 2.2 ) x 10 -20 e Life time t = λ 1/2 / ln 2 = 925 ± 11 s Magnetic moment µn = -1.04187564(26) x 10 -3 µ B = -1.91304308(54) µN Frequency nn = 1 ... 20 %. 1.2. Neutron properties Discovered by Chadwick in 1932 Rest mass mn = 1.6749543(86) x 10 -24 g = 1.008665012(37) u Temperature dependence ...

angles HOPG (002) Cu (200) take-off angle 2θ λ/Å Φ/n s-1cm-2 λ/Å Φ/n s -1 cm -2 26° - - 0.82 2.4 x 10 7 28° - - 0.88 3.2 x 10 7 30° - - 0.94 4.3 x 10 7 42° 2.41 4.2 x 10 7 1.30 9.8 x 10 7 Germanium monochromator ... 63-122° hhl λ/2 contamination at λ = 1.3 Å about 0.3 % λ/2 at λ = 2.4 Å removed by graphite filters Collimation primary collimation α1 ...

diffractometer D2B . D20 has the end-position of this tube. The 'bouchon' H11 has to be open in order to provide neutrons for all three instruments, the 'obsturateur' B2 has to be open for D2B and D20 and ... mm, Radius 1471 mm Angular aperture : horizontal = 160° Detection gap 50 mm Definition: 0.1° in 2Theta (2.568 mm) per cell (gif - 161 Ki) 1.5 ...

the orientation of the crystal lattice planes to the diffraction position. Finally the fourth circle 2θ, rotates the detector to the diffracted beam. The closed Eulerian Cradle of D9 is stout enough to

sensitive with 32 x 32 pixels Pixel size 2 x 2 mm 2 0.25° x 0.25° Sensitive area 64 x 64 mm 2 Sample-detector distance 40 cm Sample environment Displex cryostat with J-T stage 2 K Peltier cooler gas flow furnace ... neutron beam H3 Monochromators Cu (220) Take-off angle 2θM 13 - 56 ° Wavelength λ 0.25 - 0.85 Å Sample Beam size 0.6 x 0.6 cm2 ...

(111), (224) Bragg angle 2θ m 42.7°, 70° or 90° wavelength 0.8 < λ/Å <2.4 Collimation before monochromator 60' (natural) Sample max. beam size 10 mm flux 10 7 ... 10 8 n cm -2 s -1 angular range -60° < ... es, filamentous viruses), water is a key environmental parameter. The amount of H 2 O in the sample and the H 2 O/D 2 O substitution in ...