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Neutron collimators reduce the background signal in neutron experiments such as diffraction and spectrometry, by absorbing stray neutrons. Common designs include Soller and radial collimators, which typically consist of blades coated with a highly absorbing material in a parallel or diverging arrangement respectively. For more information on these collimators, have a look here.

Collimators based on blades inherently collimate in one dimension only, but advances in 3D printing technology allow more intricate designs, enabling 2D collimation. Recently we received the first proof of principle in the form of cubes, 3D-printed from enriched boron carbide powder (¹⁰B₄C). These first ‘collimator prototypes’ are 20x20x20 mm, with 5×5 mm, straight walled channels. We are currently exploring different designs and optimizing the structural integrity, vane thickness and smoothness.

Please do not hesitate to contact us if you want to learn more.

Our classic IB-C30-UHV can be modified according to our customers’ needs. An example is our nano-heat bump option as a standalone or in combination with a cooled Beamviewer. The Beamviewer is offered with boron doped diamonds and YAG:Ce. On the top of the Beamviewer, there is access to a DN100CF Port for mounting an ion pump.

We are delighted to announce that we have been selected to provide the beryllium filter for Bifrost. The ESS (European Spallation Source) spectrometer, named after the burning rainbow bridge from Norse mythology, is scheduled for hot commissioning next summer. The beryllium filter will be installed just before this time. The purpose of this filter is to remove the neutrons with wavelengths over 4 Å and to collimate the scattered neutrons. Both these measures will reduce the background noise of the spectrometer.

Bifrost is one of the eight instruments situated in the long sector of ESS, 162 meters away from the spallation target. The long distance enables a high neutron flux because the entire long pulse of ESS can be used. This unique high flux will facilitate neutron spectroscopy measurements for the fields of quantum materials, super conductivity, and magnetism. These fields are particularly relevant for the development of novel energy materials and IT applications.

When finished, Bifrost will push the boundaries of science by the high neutron flux combined with a high and flexible incident energy resolution. In addition, the spectrometer will provide increased neutron detection efficiency and extreme sample environments. Moreover, future users will be able to do their experiments on as little as one cubic millimetre of material.  As the chair of the ESS Scientific and Technical Advisory Panel, Philippe Bourges, puts it: “The instrument surpasses the current capabilities of existing inelastic neutron spectrometers by at least two-digit figures – and this is a rather conservative assessment.”

Beryllium filter design

We are extremely proud to contribute to this ambitious project with our unique knowledge of neutron collimators and years of experience with building custom designs. The design for Bifrost encompasses nine filter units with the focal point of the lamellae centred on the theoretical sample position. Each filter unit consists of beryllium wedges depicted above (in grey) mounted between borated lamellae (in brown). The copper housing facilitates cooling of the wedges to below 95 K. The filter assembly can move around the sample to enable measuring of different scattering angles. The neutrons that are not filtered out, will pass on to the spectrometer tank. Here, crystal analysers will reflect specific energies to the position sensitive detectors (see schematic figure below).

Read more about the Bifrost spectrometer here.

Read more about a similar neutron filter here.

Compound refractive lenses (CRLs) are an attractive alternative to Kirkpatrick-Baez mirrors or Fresnel zone plates as focusing elements. X-ray beamlines on Free Electron Lasers (FELs) and synchrotrons benefit from their robustness as they are less sensitive to external vibrations and surface contamination. Moreover, they preserve the beam trajectory, and their simple mechanical architecture renders them cost-effective.

An intrinsic problem of CRLs is their long focal length. This is due to the fact that the refractive index for X-rays is close to unity for all materials. This limitation is overcome by stacking multiple lenses together and by having a small radius of curvature (~50 µm). Both measures reduce the overall focal length, creating a compact focusing solution for incoming X-rays. Constant improvements in the manufacturing of thin lenses means that they can now be produced reliably and with a lower form error than ever before.

Traditionally, beryllium is the most used material for lenses withstanding energies up to 40 keV. The advantages of diamond lenses are the lack of scattering due to grain boundaries and superior thermal stability and conductivity. Furthermore, single crystal diamond lenses are applicable to nearly all energies of interest.

Advances in diamond laser ablation allow us to achieve high-level repeatability and low form errors, leading to complete freedom of operation. Moreover, the possibility to create multiple lenses in one diamond (e.g., 1D and 2D, or lenses of different sizes) offers cost-effective flexibility as it allows the user to switch between lenses with a simple translation of the CRL system.

In a ~20 minute meeting we will share the progress we have made in the processing of single crystal diamond CRLs and test results. The meeting will be followed by a live Q&A-session.

To accommodate viewing from any time zone we will hold the meeting twice:
June 15, 1.00 p.m. CDT (20.00 CET)
June 17, 11.00 CET (5.00 p.m CST)

Sign up here or read more about Single Crystal Diamond Compound Refractive Lenses on our website.

With over 200 kg, and just over a meter high, we recently delivered the biggest neutron collimator we have built until now. The picture shows the first out of six collimators for IMAT (Imaging and Materials Science & Engineering) at ISIS, with an apple for scale. This double converging collimator has an angular coverage of 56° in the vertical and 36° in the horizontal direction. It is densely packed with 361 gadolinium oxide (Gd₂O₃) coated blades spaced 0.1˚ apart. At the instrument, there will be two banks of seven large pixelated diffraction detectors, installed at 90 degree scattering angles. To obtain a higher resolution in neutron diffraction experiments, the collimator array will be placed in front of these large detectors.

IMAT is a neutron imaging and diffraction instrument for materials science, materials processing and engineering. It is a part of the ISIS neutron and muon facility. The instrument will be used for energy-selective neutron imaging, and a combination of neutron imaging and spatially resolved neutron diffraction. More information about this instrument can be found here.

The combination of these techniques allows for a variety of experiments such as radiography, neutron tomography, energy-selective imaging, neutron strain scanning, crystallographic structure and phase analysis and texture analysis.

With this wide range of imaging and diffraction techniques, this instrument is useful for scientist with backgrounds in the fields of aerospace and transportation, civil engineering, power generation, earth sciences, cultural heritage, agriculture and much more.

We are proud to contribute to these fields by providing our instrumentation and we would like to thank ISIS, and especially the people from IMAT for the fruitful collaboration. The need for these long blades required optimization of our techniques and tools. Because of these developments, we can now offer these large collimators in our standard product range.

More information about our collimators can be found here.

We are proud to announce our first contract with the SESAME synchrotron in Jordan. SESAME is the first synchrotron in the Middle East and we will supply of the front-end components for the BEATS beamline which will be used for hard X-ray full-field tomography. We are looking forward to the collaboration!

Von Hamos Spectrometers are now also offered for vacuum operation. This option is available for the smaller four-crystal version as well as the larger 16-crystal version. You can read more details about our spectrometers on our website.

A combination of copper braids and cold fingers makes this new actively cooled high vacuum slit (10^-5 mbar) a compact and cost-efficient solution for pink beam setups where UHV-operation is not necessary. For more information on IB-C80-HV-CL-50W, please contact us.

Due to increased demand, it is now possible to get the classical IB-C30-UHV slit system with a combination of passive cooling (5W per blade) and drain current. Previously, the design has been fitted for only one of these options at a time but now it is possible to combine them.

A cold head collimator has been added to our collimator portfolio. The collimator consists of beryllium wedges in a frame of copper placed inside a vacuum vessel. The cryocooler that is positioned on the top of the vacuum vessel works as a close-cycle cryostat that will cool the beryllium wedges via its connection to the copper frame.

For more information, please contact us.