1. |
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2. |
- Almehed, Sverker, et al.
(author)
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A Silicon-Tungsten Electromagnetic Calorimeter for LEP
- 1991
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 305:2, s. 320-330
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Journal article (peer-reviewed)abstract
- This report describes a silicon-tungsten electromagnetic calorimeter used to determine some beam properties and luminosity in the DELPHI experiment at LEP. The polar angular range covered by this detector is 5–8 mrad, which allows the detection of a Bhabha rate about 10 times the rate of produced Z particles at the peak cross section.
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3. |
- Andersson, Åke, et al.
(author)
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Beam profile measurements at MAX
- 1995
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 364:1, s. 4-12
-
Journal article (peer-reviewed)abstract
- An electron beam profile monitor system is described. It utilizes the visible bending magnet synchrotron radiation (SR) to form an image of the beam. A model for calculating diffraction and depth of field effects is introduced. Assuming a Gaussian distributed electron beam, the relation between beam image size and actual beam size is then calculated with this model, for a number of practical measuring situations. In a series of measurements at the MAX I electron storage ring at a current of 1 mA, the beam image size has been measured for these calculated situations. The measured values are presented, and their behaviour is in good agreement with the model. With this model the horizontal and vertical rms beam sizes were determined to σx = (203 ± 3) μm and σy = (19 ± 3) μm respectively. The corresponding vertical emittance is approximately 0.05 nm rad.
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4. |
- Andersson, Åke, et al.
(author)
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Emittance manipulation by first- and second-order lattice control
- 1997
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 387:3, s. 463-470
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Journal article (peer-reviewed)abstract
- The lattice of the MAX-I electron storage ring has been investigated and tuned towards small momentum compaction values. By measurements of the synchrotron frequency, bunch length, horizontal beam size and beam movement, the beam has been found to behave in reasonable agreement with the predictions of the lattice model up to second order in energy deviation. Both longitudinal and horizontal emittance could be varied within a relatively large range with lattice changes and/or controlled beam energy changes.
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5. |
- Andersson, Åke, et al.
(author)
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Experiences with the narrow gap undulator at MAX-lab
- 1995
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 362:2-3, s. 586-591
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Journal article (peer-reviewed)abstract
- An undulator with short poles (period 24 mm) and extremely narrow gap (magnet gap 7.7 mm) using a squeezable vacuum chamber has been installed and is in operation at the MAX-lab 550 MeV storage ring. The device operates with a vacuum chamber aperture down to 6.2 mm. The behaviour of the storage ring concerning lifetime, emittance, tune shift and closed orbit is well described by conventional models. We present here the design of the device, the influence on the storage ring and the spectral characteristics, as well as comparison with expected theoretical results and an overview of the activities at the beam line.
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6. |
- Andersson, Åke, et al.
(author)
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Positron production for ESRF
- 1988
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 267:1, s. 15-21
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Journal article (peer-reviewed)abstract
- In this report, we first discuss some different pre-injector possibilities for the ESRF booster synchrotron, using estimated machine performances. We then focus on the commercially available linac schemes carrying out more detailed calculations. We also look into the possibility of recyling the particles through the linacs.
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7. |
- Andersson, Åke, et al.
(author)
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The MAX II synchrotron radiation storage ring
- 1994
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 343:2-3, s. 644-649
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Journal article (peer-reviewed)abstract
- A 1.5 GeV third generation storage ring optimised for the VUV and soft X-ray spectral region is currently being built at MAX-lab. The magnet lattice, ring architecture and production choices are optimised to fit within rather tight boundary conditions without sacrificing performance. In this paper, the magnet lattice, light characteristics, injection and technical solutions for the ring are presented.
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8. |
- Ausmees, A., et al.
(author)
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Secondary photoelectron spectra of ionic solids as a function of the incident photon energy
- 1991
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 308:1-2, s. 219-222
-
Journal article (peer-reviewed)abstract
- Energy distributions of slow electrons (0-10 eV) emitted by thin layers of NaCl, KBr, CsBr, and CsI irradiated by monochromatic XUV photons with various energies in the interval of 50-300 eV are measured. The contributions of slow secondaries, hot secondaries and primary photoelectrons are obtained. It is shown that the higher the absorption coefficient for incident photons, the stronger the contribution of hot secondaries. The relationship between their contribution and the electron-phonon scattering process is discussed.
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9. |
- Backlund, Y., et al.
(author)
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Micromachining of Silicon for Thermal and Position-Sensitive Nuclear-Detector Applications
- 1989
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In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 279:3, s. 555-559
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Journal article (peer-reviewed)abstract
- As part of a programme aiming at the development of small nuclear radiation detectors, for example thermal detectors and position sensitive mosaic structures of surface barrier type, a technique for micromachining the detector bodies in silicon has been developed. The technique is based on an anisotropic etching property of a solution, mainly consisting of KOH. The etch rate is strongly orientation dependent with a speed in the 〈100〉 direction about 400 times faster than in the 〈111〉 direction. The major steps in the etching procedure are described and some examples of deep etching in Si are shown.
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10. |
- Bässler, M., et al.
(author)
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Beam line I411 at MAX II - Performance and first results
- 2001
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 469:3, s. 382-393
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Journal article (peer-reviewed)abstract
- We report on the characteristics and first results from the soft X-ray beam line I411, based on an undulator at the third generation synchrotron facility MAX II, Sweden. The beam line is designed for high-resolution, angle-resolved electron spectroscopy on gases, liquids and solids. Main components are the modified SX700 monochromator and the end station, both of which were previously used at beam line 51 at MAX I. The end station is equipped with a rotatable SES-200 hemispherical electron-analyser. Before the end station, a one-metre section is reserved for exchangeable experimental set-ups. The usable photon energy range is 50-1500 eV and the photon flux is two orders of magnitudes higher compared to beam line 51. At 400 eV a resolving power of about 5700 in the first order of the monochromator grating could be obtained. In gas phase, a total electron energy resolution of 16 meV has been achieved. Detailed results on the undulator performance, flux, photon and electron energy resolution as well as some technical details are presented here. As an example of the capabilities of the beam line I411, we present the fully vibrationally resolved Auger resonant Raman electron spectrum of gas-phase N 2.
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11. |
- Cronqvist, M., et al.
(author)
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Experimental-Determination of Cross-Talk between Neutron Detectors
- 1992
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In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 0168-9002. ; 317:1-2, s. 273-280
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Journal article (peer-reviewed)abstract
- Neutron cross-talk measurements have been performed with 14.1 MeV neutrons for organic scintillator detectors with n-gamma discrimination capability. The probability for cross-talk between two 156 mm thick neutron detectors with a hexagonal cross section (effective diameter 167 mm) placed 0.33 m apart was found to be (2.5+/-1.1) 10(-4). A similar measurement between two 100 mm thick, cylindrically shaped detectors with 50 mm diameter and at 75 mm distance from each other yielded a cross-talk probability of (2.5+/-0.4) 10(-3). The measured cross-talk probabilities are in agreement with values from a Monte Carlo calculation.
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12. |
- Da Via, C, et al.
(author)
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Lightwave Analogue Links For LHC Detector Front-ends
- 1994
-
In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 344:1, s. 199-211
-
Journal article (peer-reviewed)abstract
- The requirements on optical links for transferring analog and digital signals from the detector front-ends to the readout electronics at future high-luminosity colliders are reviewed. The advantages of external modulation techniques are discussed. An outline is given of the the R&D programme recently started at CERN by a collaboration involving high-energy physics institutes, optoelectronics research laboratories and industry, in order to develop electro-optic intensity modulator arrays, particularly for analogue applications, and to investigate the feasibility of volume production. The design of multichannel demonstrators in lithium niobate and III-V semiconductor technology is described. Preliminary results of the performance measurements are presented.
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13. |
- Eriksson, Mikael, et al.
(author)
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A VUV undulator for MAX
- 1988
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In: Nuclear Inst. and Methods in Physics Research, A. - 0168-9002. ; 265:3, s. 587-595
-
Journal article (peer-reviewed)abstract
- An undulator operating at radiation wavelengths between 250 and 2000 Å has been constructed at the Technical Research Centre of Finland and recently installed at the MAX storage ring in Lund. The undulator utilizes ferrite permanent magnets in the hybrid configuration. The magnetic and mechanical design, calculated performance and influence on the electron beam of the undulator are discussed.
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14. |
- Glänneskog, Henrik, 1975, et al.
(author)
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Apparatus for on-line measurements of iodine species concentration in aqueous and gaseous phases
- 2003
-
In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 0168-9002. - 9904363455 ; 498:1-3, s. 517-521
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Journal article (peer-reviewed)abstract
- An apparatus was constructed for on-line measurements of the concentration of iodine species in aqueous and gas phases using radioactive tracers. The apparatus and procedures for determining detector efficiencies and flow rates of both phases are described in detail. A complete description of experimental procedures is given and reactions between gaseous iodine and reactor containment construction materials such as copper, zinc and aluminium are investigated using the apparatus.
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15. |
- Guo, J. H., et al.
(author)
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Characterization of undulator radiation at MAXII using a soft X-ray fluorescence spectrometer
- 1999
-
In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 431:1, s. 285-293
-
Journal article (peer-reviewed)abstract
- A grazing-incidence grating spectrometer has been used for the investigation of the undulator radiation from beamline 411 at MAX-lab. The direct detection of undulator light is expected to obtain the information of the quality of the undulator. Regular undulator radiation and some higher harmonics were observed. The effects of electronic beam coupling and Landau cavities have been studied. The experiment presents an easy and quick method to characterize the undulator radiation before the permanent monochromator is installed.
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16. |
- Hedin, Lars
(author)
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Properties of electron self-energies and their role in electron spectroscopies
- 1991
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; A308:1-2, s. 169-177
-
Journal article (peer-reviewed)abstract
- The GW approximation for the self-energy connected with the one-electron Green's function has been very successful in predicting band structures for a large class of semiconductors and insulators. The physical basis for this approximation and general features of its nonlocality are discussed, as well as possible improvements. Besides quasiparticle energies the self-energy also gives the intrinsic part of the photoelectron spectrum. In general, however, a full description of experimental spectra measured with synchrotron radiation, such as photoemission, Auger spectra and EXAFS, cannot be given by the one-electron Green's function. A new theoretical approach to synchrotron radiation spectroscopies is given in terms of the coupling functions involved in the GW approximation and on-the-energy-shell one-electron Green's functions.(14 refs)
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17. |
- Jensen, B. N., et al.
(author)
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Design and performance of a spherical grating monochromator used at MAX I
- 1997
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 394:1-2, s. 243-250
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Journal article (peer-reviewed)abstract
- We report on the performance of a grazing incidence spherical grating monochromator installed at MAX I and designed to cover the photon energy range from about 15-200 eV with high resolving power. It is intended mainly for angle-resolved photoemission work. Therefore, both refocusing optics, to obtain a small spot size at the sample, and a higher order light suppressor, to reduce the content of higher orders, have been incorporated in the design. The theoretically calculated energy resolution is presented and compared to the resolution obtained in photoabsorption measurements of gas-phase He, Ne, Kr, Xe, and N2. The possibility to reduce the influence of higher orders is illustrated by photoemission data collected on Si (100). The experimental results show that the monochromator fulfills the expected design goals.
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18. |
- Levin, J.C., et al.
(author)
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Production of very cold, highly charged ions by synchrotron radiation: Comparisons of the “scalpel” and “hammer” methods
- 1987
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 262:1, s. 106-109
-
Journal article (peer-reviewed)abstract
- Measurements of kinetic energies of highy charged argon ions produced by inner-shell photoionization and by ion-beam impact have been made using time-of-flight techniques. High-charge-state recoil ions produced by beams of ∼ 0.5-1 MeV/u Cl5+ are found to have energies one to two orders of magnitude higher than ions of the same charge produced by vacancy cascades following inner-shell photoionization by synchrotron radiation. The results may have application to the development of a very cold ion source useful for angle-resolved atomic collision studies.
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19. |
- Nyholm, R., et al.
(author)
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Beamline I311 at MAX-LAB : A VUV/soft X-ray undulator beamline for high resolution electron spectroscopy
- 2001
-
In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 467-468, s. 520-524
-
Journal article (peer-reviewed)abstract
- We describe a beamline based on a plane-grating monochromator and an end-station designed for high resolution photoemission and photoabsorption spectroscopy on surfaces and interfaces using undulator radiation in the energy range 30 1500 eV. The general design of the beamline is based on a horizontally focusing pre-mirror, an SX-700 type of plane-grating monochromator and re-focusing optics of Kirkpatrick-Baez design.
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20. |
- Nyholm, R., et al.
(author)
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SURFACE SCIENCE AT MAX-LAB
- 1989
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 282:2-3, s. 553-558
-
Journal article (peer-reviewed)
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21. |
- Peterson, Carsten
(author)
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Track finding with neural networks
- 1989
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 279:3, s. 537-545
-
Journal article (peer-reviewed)abstract
- A neural network algorithm for finding tracks in high energy physics experiments is presented. The performance of the algorithm is explored on modest size samples with encouraging results. It is inherently parallel and thus suitable for execution on a conventional SIMD architecture. More important, it naturally lends itself to direct implementations in custom made hardware, which would permit real time operations and hence facilitate fast triggers. Both VLSI and optical technology implementations are briefly discussed.
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22. |
- Schulz, Joachim, et al.
(author)
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Energy absorption of free rare gas clusters irradiated by intense VUV pulses of a free electron laser
- 2003
-
In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 0168-9002. ; 507:1-2, s. 572-576
-
Conference paper (peer-reviewed)abstract
- As one of the first experiments at the free electron laser of the TESLA Test Facility (TTF) the Coulomb explosion of Xenon clusters irradiated with high intensity pulses at a wavelength of 98 nm has been observed. Classical trajectory calculations have been performed in order to illuminate the energy absorption process. Comparison with typical parameters in the infrared regime shows that above barrier ionization is suppressed due to the fast oscillating field and thermionic ionization prevails.
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23. |
- Sorensen, S.L., et al.
(author)
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A normal-incidence beam line at the MAX storage ring
- 1990
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 297:1-2, s. 296-300
-
Journal article (peer-reviewed)abstract
- A 1-m normal-incidence monochromator has been designed and installed on a bending-magnet beam line at the MAX storage ring in Lund. The optical properties of the beam line have been investigated via ray-tracing studies and with flux measurements of the beam line-monochromator combination. A resolution of 0.9 Å at 919.8 Å was measured in first-order diffraction with an argon hollow-cathode lamp for slit openings of 100 μm. A photon flux of 2.0 × 1010 at 550 Å with 250 μm slits was measured with a calibrated GaAs photodiode through a 1.5-mm diameter aperture in an aluminum mask on the photodiode. The new instrument has a microcomputer controlled mechanism which optimizes focussing requirements for a scanning monochromator with the requirement of fixed slits and fixed exit beam.
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24. |
- Vavra, I, et al.
(author)
-
The influence of thermal processing on structural and electrical properties of WxSi1−x/Si multilayers
- 1994
-
In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 350:1-2, s. 379-390
-
Journal article (peer-reviewed)abstract
- Thermal stability of WxSi1−x/Si multilayers (MLs) with x varying from 1 to 0.11 is studied by TEM and LAXS. The structure of the prepared samples is amorphous. Doping of W sublayers with silicon affects the interdiffusion process as well as the crystallization in these sublayers. We investigated these two processes (which have a detrimental influence on e.g. X-ray mirror stability) by annealing our samples at 400°C for 40 min. The structural changes were monitored by resistance measurement in the temperature range of 1.5–300 K. A correlation between structural and electrical characteristics was found, which is based on the comparison between three different R(T) curves. It is shown in our paper that the R(T) curve of a ML lies between the R(T) curves of two extreme types of single layers. The first single layer is the analogue of a fully intermixed ML and the second one represents a parallel connection of all conductive sublayers. Thus, a simple resistance measurement can give additional information about the quality of interfaces. We claim that in MLs with ultrathin sublayers the reported highest thermal stability of the amorphous mixture W0.72Si0.28 cannot be utilized because interdiffusion dominates over crystallization so that the superlattice structure is not retained.
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25. |
- Walker, R.P., et al.
(author)
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The European UV/VUV storage ring FEL at ELETTRA : First operation and future prospects
- 2001
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In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 0168-9002. ; 467-468, s. 34-37
-
Journal article (peer-reviewed)abstract
- A European project to develop the first storage ring free-electron laser on a third-generation synchrotron radiation facility is presented, including a description of the main features, initial performance at 350 and 220 nm and future prospects.
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