PERFORMANCE AND FIRST RESULTS OF THE ELETTRA HIGH-FLUX BEAMLINE FOR SMALL-ANGLE X-RAY-SCATTERING

A new beamline for small-angle X-ray scattering (SAXS) has recently be en constructed and is presently under final commissioning at the 2 GeV storage ring ELETTRA. It has been designed specifically for time-reso lved studies of non-crystalline and fibrous materials and has been opt imized for small-angle scattering measurements. The beamline operates with a SAXS resolution between 10 and about 1400 Angstrom in d spacing (at 8 keV) and has been optimized with respect to high flux at the sa mple [of the order of 10(13) photons s(-1) for 8 keV photons (2 GeV, 4 00 mA)]. Soon it will be possible to perform simultaneously wide-angle diffraction measurements in the d-spacing range 1.2-8 Angstrom (at 8 keV). In order to allow time-resolved (resolution similar to 1 ms) sma ll-angle scattering measurements, a high-power 57-pole wiggler is used as the beamline source. From its beam, one of three discrete energies , 5.4, 8 and 16 keV, can be selected with a double-crystal monochromat or, which contains three pairs of asymmetrically cut plane Si(111) cry stals. Downstream, the beam is focused horizontally and vertically by a toroidal mirror. Commissioning tests of this new SAXS beamline showe d that all design parameters have been realized.