The Influences of Material Properties to Micro Damages on Vacuum Chamber CF Flanges

The European-XFEL, a 3.3 km long X-Ray laser facility, powered by a 17.5 GeV superconducting linear accelerator, is located at DESY in Hamburg [1]. For the diagnostics ultra-high vacuum components with high mechanical precision and strict requirements on particle cleanliness had to be developed, designed and produced. For the screen system of the facility, enabling to observe the size and shape of the electron beam, massive vessels, precisely milled out of stainless steel blocks 1.4435 (316L) have been produced. For these chambers all flange-connections are milled into these blocks. This paper will report on micro damages in these integrated knife edges and will present simulations of the damage mechanisms. It will also describe the influences of material properties of two different stainless steel brands, effects on the “knife edge” due to the penetration into the gaskets as well as the non-elastic deformation of the sealing area. The dependence of tightening forces under special conditions, like the very clean conditions in particle free applications due to the non-lubricated conditions will be reported. A “cooking recipe” to avoid such micro damages will be given

The OTR Vessel Issues

49 vacuum vessels for screen monitors for the European XFEL (E-XFEL) were produced anddelivered with insufficient quality and had to be replaced by newly produced vessels. Thissummary describes the situations, the observations, the ideas to counteract and the final solutionof the issue. Some “Lessons Learned” are discussed to avoid similar problems for the future

Status Update of the SINBAD-ARES Linac Under Construction at DESY

ARES (Accelerator Research Experiment at Sinbad) is a linear accelerator for the production of low charge (from few pC to sub-pC) electron bunches with 100 MeV energy, fs and sub-fs duration and excellent arrival time stability. This experiment is currently under construction at DESY Hamburg and it is foreseen to start operation by the beginning of 2018 with the commissioning of the RF-gun. After an initial beam characterization phase, ARES will provide high temporal resolution probes for testing novel acceleration techniques, such as Laser driven plasma Wake-Field Acceleration (LWFA), Dielectric Laser Acceleration (DLA) and THz driven acceleration. In this work we present an overview of the present design of the linac with a special focus on 3D integration and planned installation phases of the beamline

First Experience with the Standard Diagnostics at the European XFEL Injector

International audienceThe injector of the European XFEL is in operation since December 2015. It includes, beside the gun and the accelerating section, containing 1.3 and a 3.9 GHz accelerating module, a variety of standard diagnostics systems specially designed for this facility. With very few exceptions, all types of diagnostics systems are installed in the injector. Therefore the operation of the injector is served to validate and prove the diagnostics characteristics for the complete European XFEL. Most of the standard diagnostics has been available for the start of beam operation and showed the evidence of first beam along the beam line. In the following months the diagnostics has been optimized and used for improvements of beam quality. First operational experiences and results from the standard beam diagnostics in the injector of the European XFEL will be reported in this contribution

First Experience with the Standard Diagnostics at the European XFEL Injector

The injector of the European XFEL started beam operation in December 2015. Besides the gun and the accelerating section, containing a 1.3 and a 3.9 GHz accelerating module, it contains a variety of standard diagnostics systems specially designed for this facility. With very few exceptions, all types of diagnostics systems of the whole XFEL are installed in the injector. Therefore the injector operation allows validating and proving of the diagnostics performances for the entire facility. Most of the standard diagnostics have been available from the very beginning of the beam operation and have been used for the monitoring of the first beam. In the following months the diagnostics have been optimized and used for improvements of beam quality. In this contribution, the first results and the operation experience of the standard beam diagnostics of the European XFEL are reported