PHELIX beamline – undulator installation and hutch construction

The PHELIX beamline construction continues. In October 2018 the light source for the beamline – an undulator – was installed in the storage ring. In November construction of the an optical hutch ended.

The hutch will protect people from radiation hazards. In the near future it will house the first optical components of the beamline.
The next planned steps are the installation of the front-end, i.e. the part of the beamline situated in the storage ring tunnel after the source (January 2019), the installation of the beamline with optical components for X-rays (February-March 2019) and the installation of the end-station (May-June 2019).

The PHELIX beamline will use soft X-rays. Its end station will enable a wide range of spectroscopic and absorption studies characterized by different surface sensitivity. In addition to collecting standard high-resolution spectra, it will allow, for example, to map the band structure in three dimensions and to detect electron spin in three dimensions. Users will, therefore, be able to conduct research on new materials, thin films and multilayers systems, catalysts and biomaterials, surface of bulk compounds, spin polarized surface states, as well as chemical reactions taking place on the surface.

>Read more on the SOLARIS website

Image credit: Agata Chrześcijanek

SESAME host to delegation from Helmholtz Association of German research centres

On 25th October, SESAME was host to a delegation from the Helmholtz Association of German Research Centres consisting of 43 persons. It was headed by Professor Otmar Wiestler, President of the Association.
The visiting delegation was shown round SESAME’s experimental hall and was able to see at first hand two of the Phase I beamlines that are already in operation, namely the XAFS/XRF (X-ray absorption fine structure/X-ray fluorescence) spectroscopy and IR (infrared) spectromicroscopy beamlines, as well as a further two Phase I beamlines, the MS (materials science) and MX (Macromolecular crystallography) beamlines, that are under construction and are expected to come on stream in two-three years.

During the visit, Otmar Wiestler informed SESAME that five research centres of the Helmholtz Association will be taking part in construction of a soft X-ray beamline for SESAME under the leadership of DESY (Deutsches Elektronen-Synchrotron). This is another of SESAME’s Phase I beamlines. The five research centres – DESY, FZJ (Forschungszentrum Jülich), HZB (Helmholtz-Zentrum Berlin), HZDR (Helmholtz-Zentrum Dresden-Rossendorf), and KIT (Karlsruher Institut für Technologie) – will be constructing a complete undulator beamline with monochromator and refocussing optics and a small chamber to conduct absorption and fluorescence yield experiments. The capital value of this work would be of the order of €3.5 million.
Given that the European Union has very recently informed SESAME that it will be providing €6 million for construction of its tomography beamline, SESAME will have six of its seven Phase I beamlines in operation relatively soon.

>Read more on the Synchrotron light for Experimental Science and Applications in the Middle East (SESAME) website

Image: (from left to right) Rolf Heuer, President SESAME Council, Otmar Wiestler, President Helmholtz Association, Khaled Toukan, SESAME Director, Walid Zidan, SESAME Administrative Director, and Rene Röspel, Member of the Bundestag and Vice-Chairman of the Science Committee of the Bundestag.
Credit: DESY

World record: Fastest 3D tomographic images at BESSY II

An HZB team has developed an ingenious precision rotary table at the EDDI beamline at BESSY II and combined it with particularly fast optics.

This enabled them to document the formation of pores in grains of metal during foaming processes at 25 tomographic images per second – a world record.

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends on the highest precision: Any tumbling around the rotation axis or even minimal deviations in the rotation speed would prevent the reliable calculation of the 3D tomography. While commercially available solutions costing several hundred thousand euros allow up to 20 tomographic images per second, the Berlin physicists were able to develop a significantly cheaper solution that is even faster. ”My two doctoral students at the Technische Universität Berlin produced the specimen holders themselves on the lathe”, says Garcia-Moreno, who not only enjoys working out solutions to tricky technical problems, but possesses a lot of craftsman skill himself as well. Additional components were produced in the HZB workshop. In addition, Garcia-Moreno and his colleague Dr. Catalina Jimenez had already developed specialized optics for the fast CMOS camera during the preliminary stages of this work that allows even for simultaneous diffraction. This makes it possible to record approximately 2000 projections per second, from which a total of 25 three-dimensional tomographic images can be created.

>Read more on the BESSY II at Helmholtz-Zentrum Berlin (HZB) website

Image: Experimental setup is composed of a fast-rotation stage, an IR heating lamp (temperature up to 800 °C), a BN crucible transparent to X-rays, a 200-μm thick LuAG:Ce scintillator, a white-beam optical system, and a PCO Dimax CMOS camera. The incident (red) and transmitted (green) X-ray beams as well as the light path from the scintillator to the camera (blue) are shown.
Credit: HZB

MAX IV becomes the first synchrotron to successfully trial neon venting from CERN

The vacuum chambers of MAXIV are only 22 mm of diameter; the chamber size was chosen in order to fit inside the compact magnets of the storage ring. Due to the small diameter of the chamber, the conventional way of pumping using lumped pumps is not efficient nor practical, accordingly, the vacuum system of the 3 GeV storage ring is fully NEG (non-evaporable getter) coated vacuum system.
NEG coating provides the needed pumping and reduces the outgassing due to the photons hitting the chamber walls. For NEG coating to be pumping down it should be activated, activation means that the coating should be heated up to around 200˚C, consequently, any venting to atmosphere will cause the NEG coating to be saturated (can not pump) and should be followed with NEG activation to restore the coating performance. At MAX IV, in order to activate the NEG coating, a major intervention is needed, where the whole achromat (23 m) should be lifted and heated up inside an oven. Such an intervention would last from 2 weeks (if the achromat does not have insertion devices) up to 4 weeks (for achromats with insertion devices).

>Read more on the MAX IV Laboratory website

 

Berkeley Lab delivers injector that will drive X-Ray laser upgrade

Unique device will create bunches of electrons to stimulate million-per-second X-ray pulses

 

Every powerful X-ray pulse produced for experiments at a next-generation laser project, now under construction, will start with a “spark” – a burst of electrons emitted when a pulse of ultraviolet light strikes a 1-millimeter-wide spot on a specially coated surface.

A team at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) designed and built a unique version of a device, called an injector gun, that can produce a steady stream of these electron bunches that will ultimately be used to produce brilliant X-ray laser pulses at a rapid-fire rate of up to 1 million per second.

The injector arrived Jan. 22 at SLAC National Accelerator Laboratory (SLAC) in Menlo Park, California, the site of the Linac Coherent Light Source II (LCLS-II), an X-ray free-electron laser project.

Getting up to speed

The injector will be one of the first operating pieces of the new X-ray laser. Initial testing of the injector will begin shortly after its installation.

The injector will feed electron bunches into a superconducting particle accelerator that must be supercooled to extremely low temperatures to conduct electricity with nearly zero loss. The accelerated electron bunches will then be used to produce X-ray laser pulses.

>Read more on the Advanced Light Source website

 Image: Joe Wallig, left, a mechanical engineering associate, and Brian Reynolds, a mechanical technician, work on the final assembly of the LCLS-II injector gun in a specially designed clean room at Berkeley Lab in August.
Credit: Marilyn Chung/Berkeley Lab

Superconducting X-Ray laser takes shape in Silicon Valley

The first cryomodule has arrived at SLAC

Linked together and chilled to nearly absolute zero, 37 of these segments will accelerate electrons to almost the speed of light and power an upgrade to the nation’s only X-ray free-electron laser facility.

An area known for high-tech gadgets and innovation will soon be home to an advanced superconducting X-ray laser that stretches 3 miles in length, built by a collaboration of national laboratories. On January 19, the first section of the machine’s new accelerator arrived by truck at SLAC National Accelerator Laboratory in Menlo Park after a cross-country journey that began in Batavia, Illinois, at Fermi National Accelerator Laboratory.

These 40-foot-long sections, called cryomodules, are building blocks for a major upgrade called LCLS-II that will amplify the performance of the lab’s X-ray free-electron laser, the Linac Coherent Light Source (LCLS).

 

>Read more on the Linac Coherent Light Source website

Photo credit: Fermilab / Jefferson Lab