For a presentation of the SAXS basic theory, techniques and applications, you can download the book Small Angle X-ray Scattering (O. Glatter and O. Kratky Eds., Academic Press, 1982) from http://physchem.kfunigraz.ac.at/sm/ (Scattering Methods at the Chemistry Department, University of Graz).

For a more biologically oriented introduction one can download Structure Analysis by Small-Angle X-Ray and Neutron Scattering (L. A. Feigin and D. I. Svergun, Plenum Press / Springer, 1987) from http://www.embl-hamburg.de/ExternalInfo/Research/Sax/publications.html

From a practical point of view, you might want to take a look at the Beamline Manuals page. One can find there a short User's survival manual, the full manual of the data acquisition and reduction software for collecting and pre-processing SAXS and/or WAXS data for both static and time-resolved measurements on beamline BM26B, as well as a list of basic Unix commands.

Last but not least, the Data Reduction and Analysis page provides the response of the detector in use, together with links to data reduction and analysis software.

The station

Photo: Daniel Michon, ARTECHNIQUE

With the SAXS/WAXS station one can simultaneously obtain wide- and small-angle scattering patterns. This photograph shows the SAXS station. Here the SAXS pattern is collected by a 1D quadrant but area detectors are also available. The WAXS pattern was initially detected by a curved linear detector, now replaced by a 2D device (cf. WAXS detectors).
The low angle resolution of the SAXS station is dependent on the X-ray wave length and the sample-to-detector distance.

SAXS detectors

Currently, one can use as SAXS detector either a Multiwire Proportional Counter (see below) or a FReLoN 2k CCD camera.

• A description of how the gas-filled wire chamber detectors operate can be found in A. Gabriel and F. Dauvergne, The localisation method used at EMBL, Nuclear Instruments and Methods 201 (1982), 223-224.
• The operating principle of the 1D quadrant detector is explained here.
• A basic presentation of the FReLoN camera is given here; technical data sheet is available here.
• An abstract about the position sensitive detector technology, data reduction, and count rates can be downloaded here (as pdf).

Wire chamber detectors

Characteristics

Detector calibration

• Silver Behenate Peak Positions
• Rat Tail Positions 

FReLoN 2k camera

The FReLoN 2000 (the acronym stands for Fast-Readout, Low-Noise) is a CCD camera developed by the ESRF Instrument Support Group.

Technical data sheet is available here.

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WAXS detectors

WAXS data can currently be acquired using a CCD-based X-ray digital camera: either the FReLoN 2000 (2048×2048 pixels), or a VHR (2657×3955 pixels) from Photonic Science. In the near future, they will be replaced by a Pilatus 300K-W detector from Dectris.

Pilatus is a state-of-the-art detector family with remarkable characteristics. Our system is the first Pilatus at the ESRF. It arrived at Dubble at mid April 2009 and has been successfully tested with beam.

General characteristics

• operates in single-photon counting mode
• based on CMOS hybrid-pixel technology
• high frame rate
• air-cooled => simple in operation and handling
• PC with Linux OS (Suse 10.3) + a data acquisition and analysis software (TVX)

Technical specifications

For those who might miss the old MSGC (MicroStrip Gas Chamber) detector, some information about it is still available here.

Detector calibration

• HDPE Peak Positions
• NBS Silicon Powder

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