GILDA BeamLine

G I L D A

General purpose Italian beam Line for X-ray Diffraction and Absorption

Consiglio Nazionale delle Ricerche	Istituto Nazionale per la Fisica della Materia	Istituto Nazionale di Fisica Nucleare

 

 

The GILDA Beamline

The Italian Collaborating Research Group GILDA at ESRF is a general purpose beamline using a bending magnet source. It is financed by three major italian public research Institutes (Consiglio Nazionale delle Ricerche CNR , Istituto Nazionale per la Fisica della Materia INFM and Istituto Nazionale di Fisica Nucleare INFN ) and is the result of a collaboration a number of Italian Universities namely Cagliari, Camerino, Roma "Tor Vergata", "Roma Tre", Parma, Trento

, ).

 

It is operational since Sept 1994, and is mainly dedicated to the investigation of local structures. To this purpose, X-ray Absorption Spectroscopy as well as X-ray Diffraction are used on the beamline in the energy range 5-80 keV. A high energy resolution is ensured by using Si(311) and Si (511) monochromating crystals. The GILDA beamline consists in four experimental hutches: the first contains the optical elements and the others the experimental apparata.

 

The first experimental hutch, in the 1:3 focal configuration which ensures the maximum flux, is dedicated to X-ray Absorption Spectroscopy (XAS). The wide energy range of the beamline makes GILDA well-suited for XAS investigations on heavy elements with the possibility to access the K absorption edges from Ti to Au. Experiments are carried out in transmission, fluorescence and total electron yield modes. For the study of highly diluted samples a 13-elements high purity Ge detector is currently used (current limit sensitivity: 10¹⁴ at/cm²

). Surface experiments in total reflection mode (ReflEXAFS) are performed in a dedicated experimental chamber.

 

The second hutch, in 1:1 focal geometry, is dedicated to X-ray scattering and diffraction. It is equipped with a two circle diffractometer with an angular step of 0.28 arcsec and a reproducibility of 2 arcsec. Crystal analyzers, solid-state detectors and scintillators are used to perform anomalous scattering on amorphous materials, and powder diffraction with an instrumental angular resolution lower than 0.01 degree. The recent installation of an Image Plate detector has permitted the development of an apparatus for time-resolved powder diffraction.

A third experimental hutch at the end of the beamline is available for users who wish install their own apparatus. An ultra high vacuum chamber fully equipped for surface preparation and characterization is available for EXAFS investigations in total and partial electron yield mode.

 

Last revised Apr 2012 by F. d'Acapito .