LNLS Synchrotron, Brazil
The synchrotron radiation source which is being constructed at LNLS (Laboratório Nacional de Luz Síncrotron) is composed of a 100 MeV LINAC injector and a 1.15 GeV electron storage ring. Two beamlines and workstations are completed and five are under construction. They are associated with several experimental techniques, including VUV and X-ray spectroscopies and X-ray diffraction and scattering.
The LNLS storage ring, to be commissioned at the beginning of 1996, is a sixfold symmetric double-bend Chasman-Green achromat lattice. Four of the six dispersion-free straight sections are available for insertion devices, each with a useful length of 3 meters. At the moment, the construction of most of the components of the injector and storage ring (excepting the wigglers) has been completed. Parallel to the construction of the synchrotron source, the LNLS is working on the design and construction of the beamlines associated with different experimental techniques and applications.
- XAFS (XANES and EXAFS)(X-ray Absorption Near-Edge Structure and Extended X-ray Absorption Fine Structure)
- Applications: Local atomic structure of disordered materials (glass, multilayers, composites, catalyzers, etc.), electronic and magnetic structure of solids.
- TGM (Toroidal Grating Monochromator)
- Applications: Surface physics, surface chemistry, molecular spectroscopy, electronic structure of condensed matter, mass spectroscopy.
- SGM (Spherical Grating Monochromator)
- Applications: High-resolution soft X-ray spectroscopies, electronic and magnetic properties of materials.
- Soft X-ray Spectroscopy
- Applications: Soft X-ray spectroscopy of transition metals and rare earth systems (thin films, multilayers, alloys, and compounds), core level spectroscopy.
- X-ray Diffraction
- Applications: Multiple-axis goniometry: rocking curves, standing waves, backdiffraction, topography, multiple diffraction, grazing incidence. Q and 2Q goniometry: Debye-Scherrer powder diffraction, texture, structural characterization of epitaxial layers and nanostructures. Single- and multiple-crystal optical studies and devices. Metal and alloy surface studies: high temperature corrosion and recrystallization.
- SAXS (Small-Angle X-ray Scattering)
- Applications: Heterogeneous materials, characterization of fractal structures, micro porous materials, microphase separation, composite glass-semiconductor nanocrystals, gels, proteins in solution.
- Protein Crystallography
- Applications: High-resolution structure determination of crystallized proteins and other macromolecules of biological importance.
The first two workstations described above were constructed at LNLS and are already in operation at the Center for Advanced Microstructures and Devices (CAMD, Louisiana State University), four are under construction at LNLS, most of them in collaboration with external users, and the last is in the design stage. Additional technical information about the different workstations under construction at LNLS or now in operation at CAMD may be requested from the authors at Laboratório Nacional de Luz Síncrotron/CNPq, Inst. de Física, CP 6192, 13081-970 Campinas, SP, Brazil.C. E. T. Gonçalves da Silva, A. R. D. Rodrigues and A. F. Craievich