The first experimental hutch contains a heavy duty Huber diffractometer with vertical rotation axis and FReLoN 2K CCD camera.

Photographs of the detector - diffractometer - slits assembly in EH1 as viewed from down stream and above. A gantry can be seen above the diffractometer which can hold further detectors (microscopes / fluroescence / ..) or sample environment (cryostream / ..). 

Beam definition

The beam in EH1 can be focused using the IVT in OH1 down to a size of ~ 45 x 6 micron (horizontal x vertical) for an energy range of 18-75 keV (see figure here). The beam then can be further defined using the slit system situated on the 'huber tower'. This consists of a set of xx type slits (slit6) mounted infront of a further set of huber tube slits (see image below). The tube slits are in-vacuum allowing a means of defining the x-ray beam as close to the sample position as possible and reduce the effect of air scattering. They also act as anti-scatter slits when s6 is used to define the beam. For users doing standard diffraction experiments in EH1 using the FReLoN camera, it is recommend to use a 50 x 50 micron beamsize to match the pixel size of the detector.

Photographs showing the beam defining apparatus available in EH1, consisting of a set of regular slits preceeding a set of huber tube slits.

Diffractometer

The huber diffractometer was installed in 2008 and offers a very large working area and load capacity (>100 kg) for complex sample environments, while maintaining ~2 micron sphere-of-confusion (SOC) and linear positional accuracy. Either white beam or monochromatic x-ray beams are available, with energies of 25-140 keV and sizes of 0.8x0.8 mm down to ~20 x 7 (HxV) microns. By exploiting the fast readout of the Frelon camera and high x-ray flux, 2D diffraction images can be collected very quickly, allowing time resolved in-situ studies to be carried out. Due to the vertical rotation axis, this instrument can also be used for single crystal diffraction. If required, a second rotation axis can be added in a fixed kappa angle geometry to provide single crystal data which are highly complete and redundant. 

Photographs and schematic showing the translations and rotations available on the EH1 diffractometer (hz - hz2) and 'huber tower' (hsz & hsy) which holds the slits, huber (hs) and regular (s6). Both are mounted on an 'x' translation (diffx) if the transfocator is used for focussing of the beam at the sample position. Above is also a schematic of the beam direction and a compass showing the standard lab coordinate system.

Typical detector arrangement

The detector (typically a FReLoN 2k, 2 dimensional CCD detector) is mounted on two x-translations, allowing a wide range of Q to be accessed depending on the detector- beam stop & detector - sample positions. There are also two z-translations, allowing the detector to be tilted. Other motors are also available, though not pictured, which may be mounted on the diffractometer such as a sample spinner and other angluar rotations.

Photographs and schematic showing the detector tower arrangement and translations. In the bottom left photo, mounted on 'diodey' is a lead screen that can be placed infront of the camera for high speed, time resolution studies.

EH1 control room