共查询到20条相似文献,搜索用时 12 毫秒
1.
2.
3.
The results of high-heat-load tests of indirectly cryogenically cooled silicon monochromators are presented. The measurements show that, provided that the total power absorbed by the crystal is less than approximately 150 W, indirect cryogenically cooled silicon monochromators will perform well, with thermal-induced slope errors of less than 2 arcsec. At the Advanced Photon Source, this corresponds to the undulator closed-gap (11 mm) condition at 100 mA with white-beam slit sizes slightly larger than the full width at half-maximum of the radiation central cones. The dependence of the slope errors on the thermomechanical properties of silicon are discussed and clearly demonstrated. 相似文献
4.
5.
The more recent developments in the spectroscopy of Nuclear Magnetic Resonance on Oriented Nuclei (NMRON) are reviewed; both
theoretical and experimental advances are summarised with applications to On-Line and Off-Line determination of magnetic dipole
and electric quadrupole hyperfine parameters. Some emphasis is provided on solid state considerations with indications of
where likely enhancements in technique will lead in conventional hyperfine studies. 相似文献
6.
7.
8.
The Canadian Light Source (CLS) is constructing two beamlines for Infrared Spectroscopy using synchrotron radiation (IRSR). One will supply mid-Infrared (2–25 μ) light to a Fourier Transform Infrared (FTIR) spectrometer and microscope for biological applications. The second will have a high resolution FTIR spectrometer for gas-phase and surface spectroscopy in the far-Infrared (beyond 25 μ). The Infrared beamlines will use dipole bending magnet radiation from a special bend magnet port design which provides a 50 mrad square acceptance. Issues with the first mirror and photon mask design, as well as the beamline layout and features are discussed. 相似文献
9.
A secondary pion beam facility has recently been installed and commissioned at the SIS-GSI (Darmstadt) 18Tm synchrotron. Pions are produced in the collision of light heavy-ion beams from the SIS onto a thick production target and transported to HADES experimental area. A system of three time-of-flight hodoscopes has been constructed and installed in the beam line to separate pions from other secondary particles. The main results of the commissioning experiment are presented. 相似文献
10.
NMR on brute force oriented nuclei (NMRON/BF) has been observed for110mAg in elemental silver. Resonances have been measured at approximately 7 T and 8 T with the resulting gradient of 4.583(5)
MHzT−1 which produces a value for the110mAg moment of μ=3.589(4) nm (uncorrected). Factors pertinent to successful NMRON/BF in systems such as110mAgAg, with a complex decay scheme and modestg-factor, are also discussed. 相似文献
11.
B. van den Brandt M. Daum P. Hautle J. A. Konter S. Mango P. A. Schmelzbach Ph. Demierre N. Goujon E. Heer E. Hess C. Lechanoine-Leluc A. Teglia D. Rapin B. Vuaridel J. Arnold J. Franz H. Lacker M. Schmidt E. Rössle R. Schirmaier H. Schmitt M. Finger M. Slunecka R. Drevenak M. FingerJr A. Janata F. Lehar 《Czechoslovak Journal of Physics》1999,49(2):23-28
The new nucleon area (NA) at PSI is designed as a multi-purpose facility with nucleon beams. The area can be used for experiments with polarized or unpolarized protons or neutrons. For both kinds of nucleons the available energy ranges from about 100 MeV up to a maximum of about 590 MeV. 相似文献
12.
The ISIS pulsed surface muon facility at RAL is presently undergoing a major expansion to provide three experimental ports with simultaneous single muon pulses at 50 Hz. This upgrade, funded by the European Community (EC), is described together with recent development results which are relevant to its future scientific programme. These new beam lines are expected to be available for experiments in June 1993. 相似文献
13.
14.
S. Schwarz C. Bachelet M. Block G. Bollen D. Davies M. Facina C. M. Folden III C. Guénaut J. Huikari E. Kwan A. A. Kwiatkowski D. J. Morrissey G. Pang A. Prinke R. Ringle J. Savory P. Schury C. Sumithrarachchi T. Sun 《Hyperfine Interactions》2006,173(1-3):113-122
The low-energy beam and ion trap facility LEBIT at the NSCL at MSU has demonstrated that rare isotopes produced by fast-beam
fragmentation can be slowed down and prepared such that precision experiments with low-energy beams are possible. For this
purpose high-pressure gas-stopping is employed combined with advanced ion manipulation techniques. Penning trap mass measurements
on short-lived rare isotopes have been performed with a 9.4 T Penning trap mass spectrometer. Examples include 66As, which has a half-live of only 96 ms, and the super-allowed Fermi-emitter 38Ca, for which a mass accuracy of 8 ppb (280 eV) has been achieved. The high accuracy of this new mass value makes 38Ca a new candidate for the test of the conserved vector current hypothesis.
相似文献
15.
P. Herzog U. Dämmrich K. Freitag C. -D. Herrmann K. Schlösser J. C. Soares 《Zeitschrift für Physik B Condensed Matter》1986,63(2):241-246
Nuclear magnetic resonance of175Hf oriented at low temperature in iron has been observed with a sample prepared by ion implantation. The centre frequency of the broad resonance line isv L (B ext = 0)=138.53(36)MHz. Possible origins of the large inhomogeneous line width of FWHM=11.0(1.1) MHz are discussed. A comparison with model calculations for combined magnetic and electric hyperfine interaction indicates that the centre frequency may be interpreted as the magnetic interaction frequency for175Hf in unperturbed substitutional sites of the host iron. With theg-factor of175Hf from literature the magnetic hyperfine field of Hf in Fe is derived asB hf=?64.9(9.3) T fitting well into systematics. 相似文献
16.
17.
E. Van Walle D. Vandeplassche J. Wouters N. Severijns L. Vanneste 《Hyperfine Interactions》1987,34(1-4):105-109
Since the previous conference we extended our series of on-line -anisotropy measurements in the Z=50 and Z=82 region leading a.o. to the identification of the phase transition in the Au isotopes. Besides conventional on-line low temperature nuclear orientation, we introduced the first on-line applications of NMR/ON, on-line -anisotropy measurements and -decay asymmetry experiments. The intriguing information from these new developments both in the field of nuclear structure and solid state physics is briefly discussed. 相似文献
18.
M. Allaire M. Aslantas A. Berntson L. Berman S. Cheung B. Clay 《Synchrotron Radiation News》2013,26(6):20-25
FLASH at DESY in Hamburg, the first and currently only free-electron laser for VUV and soft X-ray radiation, started user operation in the summer of 2005. Currently it covers a wavelength range from 13 nm to 50 nm with GW peak power and pulse durations between 10 fs and 50 fs. Approximately 20 weeks of beamtime are provided per year for scientific experiments that are not possible on any other radiation source. 相似文献
19.
T. Kambara 《Hyperfine Interactions》1998,112(1-4):101-106
Combining Mössbauer spectroscopy with magnetic property measurement, we have studied Fe-N and (Fe, Ni)-N powders for magnetic recording. The typical particles of the core (α-Fe)/shell (γ′-Fe4N) structure have been successfully prepared. All the products are stabilized in a multi-organic solution. It has been found that the coercivity can be changed from 300 to 800 Oe by adjusting the shape of the particles. The special saturation magnetization of the particles can be adjusted from 120 to 180emu/g and their chemical stability is improved by substituting nickel for iron in γ′-Fe4N. Following experiments for corrosion resistance, it is expected that (Fe, Ni)-N and the core/shell particles will be applied as recording media in the near future. 相似文献
20.