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Forskningsprojekt Europeiska XFEL

European XFEL är en mer än 3 km lång frielektronlaser (FEL) som togs i drift i Hamburg 2017.

Elektroner som avger röntgenstrålar i Eu XFEL-undulatorn
Elektroner som avger röntgenstrålar i Eu XFEL-undulatorn

Här avger elektroner röntgenstrålar (1 Å) i ljuspulser med hög effekt och med laserliknande egenskaper som kan användas för att filma molekylära reaktioner och undersöka atomära detaljer i virus och celler. Instrumentationsfysik har varit involverad i flera projekt i uppbyggnadsfasen och vi undersöker för närvarande oönskad joniserande strålning som orsakar avmagnetisering av permanentmagnetmaterial i undulatorn.

Projektbeskrivning

The European XFEL is a more than 3 km long free electron laser (FEL) commissioned in 2017 at DESY in Hamburg, Germany.

Electrons emitting X-rays in Eu XFEL undulator
Electrons emitting X-rays in Eu XFEL undulator
Electrons will be accelerated in a superconducting accelerator to high energies (17 GeV) before traveling through a magnetic structure (undulator) where the bunched electrons emit X-rays (1 Å) in light pulses of high power and with laser-like properties. Sweden is one of twelve countries involved in the construction if the XFEL and the Instrumentation physics division has worked on several projects. The machine was commissioned in 2017 and will open up new areas of research, for example 3D-imaging with near atomic resolution of viruses and other previously inaccessible samples.

Instrumentation physics has been involved in several projects such as constructing a timing and synchronization system for the XFEL control and diagnostics, fiducialization of focusing quadrupole magnets, high accuracy temperature system for magnetic field compensation and a dosimetry system to measure the integrated dose in the in the permanent magnets material in the undulator.

Since commissioning, RadFET sensors positioned in front of the undulator segments monitor the ionizing radiation caused by stray electron hitting the vacuum chamber along the undulator. In addition, Gafchronic films positioned on the magnetic poles yield the distribution of radiation along each undulator segments. Together with simulations using the GEANT4 software it is possible to draw conclusions about the radiation field in the undulators. This will also be compared to measurements of the magnetic flux degradation in order to study the demagnetization of the permanent magnet material.

Projektmedlemmar