Calls for Proposals

The Alvra instrument specializes in ultrafast dynamics in chemical and biological systems, especially in solutions, liquids, or crystals in viscous media. Alvra is equipped for X-ray spectroscopy (absorption and emission), liquid scattering, and serial femtosecond crystallography measurements, as well as flexible user-provided setups. For the current call, the Alvra Prime instrument (vacuum and He environment) is available for liquid jet spectroscopy setups. The details are described below.

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

The Bernina Instrument is specialized on studying condensed matter systems by selective light excitation and selective X-ray probes. It is equipped with flexible but precise positioning hardware for diffraction on solid state samples, but also larger user-supplied hardware. The instrument can interchange two endstations, which can be configured for different sample and detector configurations. Bernina features versatile pump laser excitation from UV to single cycle THz pulses.

For the call of 2025A experiments, the flexible Bernina endstation platform will be limited to the following standardized configurations:

• Six circle kappa surface diffractometer, equipped with area detector on 2-circle detector arm (XRD). Sample in air or N2-cryostream atmosphere (80-500K stream temperature). Standard pump laser wavelengths from UV to near Ir. An optional polarisation analyzer can be used upon early request.
• Vacuum chamber setup for low sample temperature (down to ~5K), high electric field THz pulse excitation, and tender X-ray range experiments. It is advised to explore the compatibility of proposed experiments with the chamber geometry before proposal submission. For details about the chamber please refer to https://doi.org/10.1088/1361-648X/ac08b5

Experiments requiring a custom assembly using the flexible platform are encouraged to start communication with the Instrument staff and potentially submit a proposal for early evaluation of technical and scientific feasibility of their idea, respectively. 

New developments

• Visible short pulse pump (500 – 750 nm; ≤ 25 fs fwhm) by Non-Collinear Optical Parametric Amplifier (NOPA).
• Load lock for High-field THz cryo chamber for quick sample exchange and transfer from inert atmosphere (under commissioning, usable upon request).

For high time resolution experiments, a single pulse timing diagnostics is used for time-delay feedback and time delay measurement close to pulse length limit. The diagnostics works reliably at Si-111 monochromatic and pink FEL beam.

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

The first Cristallina-MX experimental station is called SwissMX (Serial WIth Solid-Support MX), a fixed-target setup designed for high-throughput SFX and SFX pump-probe. SwissMX has been commissioned with an in-air sample environment since May 2022 and is currently available for users.

The SwissMX has currently only been commissioned to accept two styles of fixed-target: the PSI MISP (MIcro-Structured Polymer) and the MPI SOS (Sheet-On-Sheet) chip (Doak et al., 2018). The MISP-chip is composed of an array of apertures in defined locations in a similar style to the Oxford (Horrell et al., 2021) and HARE chips (Mehrabi et al., 2020). The MISP-chips can be fabricated in either a clear or an opaque polymer, with the only latter being compatible with pump-probe measurements. The SOS chip by comparison is made by carefully sandwiching a sample between two sheets of polymer film and are ideal for samples of limited volume in viscous media such as LCP. Liquid-crystal samples will need to be embedded in a moderately viscous medium to be used effectively. Please indicate in the DUO which chip or both you would like to use.

The SwissMX is capable of both SFX and nanosecond resolution SFX pump-probe measurements. An EKSPLA nanosecond OPO can be used for pump-probe measurements and has been commissioned using the opaque MISP chips. Pump-probe is only possible using these chips.

Our standard SFX beamtime configurations are: X-ray photon energy of 12 keV with standard bandwidth (0.15 % SASE), nano-second laser excitation between 410 nm - 700 nm (if required), Jungfrau 8M detector and either MISP or SOS chips. Max beamtime length will be 2 days (6 shifts). Please indicate if you would only like 0.5/1 shifts for non-pump-probe SFX measurements.

General information can be found at the Cristallina-MX project page.
For questions and further information about Cristallina-MX, please contact: Dr. John Beale

The Cristallina-Q team has recently commissioned an experimental station named Ultralow-T Vectormagnet that enables resonant and non-resonant X-ray diffraction in high-magnetic fields and sub-Kelvin temperatures. It includes a dedicated cryostat with beryllium and mylar windows for the incident and the diffracted beams in the horizontal diffraction plane. The cryostat is installed on a heavy-load diffractometer to orient the sample with respect to the vertical axis (θ), as well as to position the detector at the Bragg angle (2θ) and at a suitable distance from the sample. The beam size on the sample can be varied by means of bendable KB focusing mirrors. The station can be placed at custom distances from the last KB mirror.

The ultralow-T sample environment requires mounting the sample and closing the cryostat at least 1 week before the beamtime start, to allow for cooling to the base temperature and offline tests. Depending on the requested measurement temperature and the sample properties, reduced repetition rates and/or high attenuation have to be used to ensure recovery of sub-Kelvin temperatures between subsequent X-ray pulses. Because of the latter, it is advantageous, although not mandatory, to operate the ARAMIS beamline in the ultrashort pulse mode such that that thermal and electronic modification of the sample can be outrun.

In this first user call, the capabilities of the Ultralow-T Vectormagnet are restricted in terms of the maximal θ range, due to mechanical limitations, and to higher photon energies to cope with in-air propagation and due to absorption of the X-ray windows.

General information about the Cristallina-Q experimental station can be found at: Cristallina-Q.

Because of the novelty of this experimental station, the inherent challenges due to the ultralow-T environment, and operational limitations, proposers must contact the Cristallina-Q team well ahead of submission.

The Maloja instrument specializes on studying ultrafast processes in atomic, molecular, non-linear and chemical sciences. The flexible setup allows for a variety of spectroscopy and imaging approaches. For the current call only the following standard setups and parameters will be available:

Natural jitter between X-ray and optical pulse ~150fs (FWHM), which can be improved with an arrival time monitor.

Restrictions for hazardous samples apply, please consult with the Maloja contact before submission in case you plan to use such substances.

General information about the Maloja endstations can be found at: Maloja
For questions and further information about Maloja contact: Dr. Kirsten Schnorr

The Furka experimental endstation, located at the soft x-ray Athos beamline of the SwissFEL, is dedicated to the study of quantum materials using time-resolved Resonant Inelastic and Elastic X-ray Scattering (tr-RIXS and tr-REXS) as well as X-Ray Absorption (tr-XAS) spectroscopy.

The endstation is equipped with at 4-circles UHV diffractometer (Tmin=25 K), a set of x-ray detectors (APDs) rotating on two independent circles around the sample and 6 meter long RIXS spectrometer (200 meV min energy resolution).  Sample cleaving in the load lock (room temperature, vacuum 10-7 mbar) is available. The THz radiation is focused using a parabolic mirror mounted on a motorized manipulator (5 DOF) located inside the vacuum chamber.

Natural jitter between X-ray and optical pulses ~150fs (FWHM). For higher time resolution experiments, a single pulse timing diagnostics, for jitter and drift corrections, can be used (please contact instrument responsible for more info).

General information about the Furka endstations can be found at: Furka
For questions and further information about Furka contact:  Dr Elia Razzoli