Table of Content

• The PSI User Office invites user proposals for the first user run at SwissFEL.
• SwissFEL is being continuously developed but the proposals must be based on the parameters outlined below on this page
• After the submission deadline the proposals are evaluated in terms of safety and technical feasibility. Then they are ranked in terms of scientific criteria by the international SwissFEL Proposal Review Committee (PRC). More information about the evaluation procedure is published on Evaluation. The result of this rating is the basis for the beamtime assessment made by SwissFEL.
• The main proposers are informed by email about the result of the ranking and beamtime assessment.
• The annual calendar for the proposal evaluation is as seen below.

Schedule for Calls

We will open a call for proposals for SwissFEL on February 8, 2021. 

Current achieved parameters (February 7th , 2020)

• photon energy: 1.8-12.4 keV (12.7 keV is also possible)
• typical bandwidth: 0.25% dE/E, larger bandwidth up to 2% also feasible (photon energy dependent)
• typical pulse energies: 200-600 µJ
• repetition rate: single shot - 25Hz (50 Hz possible under certain conditions)
• X-ray pulse duration: 50 - 100 fs fwhm (shorter pulses possible but with a linear decrease in photon flux)
• X-ray-laser arrival-time jitter: ~ 200 fs fwhm

Please note, that due to the early operation phase of the SwissFEL facility, the evolution in 2020 toward advanced parameters is based on best effort. In addition, due to the concurrent buildup of the ATHOS branch, technical feasibility and resource requirements will be strong criteria in the evaluation.

Experimental Endstations

For the new run the Alvra and Bernina endstations are available with the following parameters:

Alvra Instrument

The Alvra end station of SwissFEL specializes in measuring the ultrafast dynamics of photochemical and photobiological systems using a variety of X-ray scattering and spectroscopic techniques. For the Alvra branch, the Alvra Prime chamber and Alvra Flex in-air instruments will be available with the following parameters.

General information about the Alvra endstations can be found at: Alvra
For questions and further information about Alvra contact: Dr. Chris Milne

Bernina Instrument

The Bernina Instrument is designed for studying condensed matter systems by selective excitation and probes, with emphasis on flexible but precise positioning hardware for diffraction on solid state samples. The instrument can interchange large endstations on rails transverse to beam direction. Two configurable endstation platforms are  permanently installed, both having a single vertical axis sample rotation:

• X-ray Diffractometer (XRD), equipped with a two circle detector arm,
• General Purpose Station (GPS), with a multi-purpose horizontal 2-theta arm.

Both endstations can be completed with different sample platforms that allow a large range of of specialized sample environment being precisely positioned:

• Six degree of freedom (DOF) heavy load goniometer,
• Two-circle surface diffractometer combination plus hexapod,
• Kappa arm (6 DOF).

An additional 6 DOF robot arm can be used for flexible detector positioning.

For specific high time resolution experiments a temporarily installed timing diagnostics can potentially be combined with the setup after careful planning with the Bernina staff.

General information can be found at: Aramis Bernina Experimental Endstations
For questions and further information about Bernina contact: Dr. Henrik Lemke