Instrument Capabilities - Call for proposals

The 14th call for proposals is open until Tuesday 24 June 2025, at 16:00 CEST . You will be able to submit proposals for beamtime between April-December 2026. The text of the general facility-wide call you find here. On this website you we provide you with information about the current capabilities of HED-HIBEF. It is mandatory to contact the instrument scientists well before the submission of proposals in order to discuss technical feasibilt of your porposal and suggest potential improvements to make best use of the facility.

 

You have never been to HED-HIBEF? Then take a virtual tour to the hutch.

Instrument-relevant publications

X-ray delivery parameters

 

Standard SASE operation mode

Bunch distribution: up to 350 X-ray pulses per instrument assuming the equal distribution at 2.25 MHz, or ~200 µs are available. If you need higher or smaller numbers for higher/smaller intra-train frequency, please contact instrument scientists.

Pulse energy: around 2 mJ (SASE) from 5-9 keV, 1 mJ between 9-12 keV, and 0.5 mJ availabe 12 keV (getting weaker with higher photon energies).

 

Special modes (require more tuning and are less reliable)

a. Hard X-ray self-seeding (HXRSS) (SA2; 7 - 14 keV)

b. Hard X-ray two-colour w. variable delay (SA2; 6–10 keV; 0–0.5 ps)

c. Short bunches (< 10 fs FWHM); requires coordinated scheduling as other instruments and available number of bunches might be affected; time-diagnostics is only partially available

d. Full trains at instruments with rep. rates much lower than 10 Hz  (~ max. 2250 pulses)

 

Experiments requesting these special modes should address the development of new techniques and fields and are expected to involve large communities and facility staff. Since there is a vast range of detailed specifications for these special modes, proposers are requested to contact instrument staff before submission in order to clarify requirements.

 

Full-train delivery (special mode d)

This mode sends the full can send 352 pules in 550 µs (at 500 kHz rate) to HED, but only every 10 seconds. We use this mode for dDAC and pulsed magnetic field experiments. The accelerator would run normally, where each train would deliver a portion of the RF window to each SASE. Then, every 10s,  a full train (full RF window) would go ONLY to SASE2 (HED). This means that SA1 and SA3 “miss” one train out of 100.

The EuXFELs timing system is absolutely capable of this mode. However the various feed-backs and feed-forwards that are presently optimised for each beamline separately will have to work on a common setpoint. The operators usually tune for a 'compromise' working point that works for all cases, but would not reconfigure the linac for a single pulse every 10s. So every SASE would operate with a not optimal working point all the time. As a consequence we estimate a systematic about 30% less intensity at compared to the standard modes.

 

Photon delivery to your experiment at HED-HIBEF

 

  • 5-24 keV x-ray photon energy SASE spectrum (about 0.2..0.3 % bandwidth), usually about 1-2 mJ pulse energy in ~20-40 eV bandwidth

  • Seeded x-rays between 7-14 keV (~1 eV spectral width), few 100 µJ

  • Single pulses/trains on demand, or 10 Hz continuous pulse trains of 2.25 MHz (440 ns) or less (down to single pulse on demand)

  • One week with 4.5 MHz rep. rate (222 ns pulse spacing) per run

  • 4-bounce monochromator (1 eV bandwidth) at max. 10 Hz between 5-18 keV (please contact Karen Appel before to talk about transmission and stability of this mono).

  • High resolution-mono fixed to 7.49 keV  with about 45 meV bandwidth) at 10 Hz

  • full focusing capability CRL 1,2,3,4 - any focus from parallel beam (few µrad divergence) down to slightly less than 1 µm foci, however with potentially significant absorption in the Be lenses. The feasibility of sub-micron foci at any photon energy has to be discussed with the instrument scientists before submission.

  • diamond focusing lenses, please contact instrument scientists for details.

  • “HIREX2” spectrometer, far upstream in the SASE2 branch (before the separation into MID and HED) for monitoring the incident SASE / seeded spectrum.

 

 

Considerations when choosing a photon energy

The linac of EuXFEL has specific electron energy setpoints, 11.5, 14, and 16.5 GeV.

At 11.5 GeV, the available photon energy range at SASE2 and HED is 5-9 keV,
it can be extended to higher values but the intensity will drop significantly. Even at 8-9 keV, the pulse energies will probably not exceed 0.3 mJ. 14 GeV:~6 - ~ 15 keV, 16.5 GeV: 8.2 – 25 keV, respectively.

It is not possible to change between 5-6 keV and 12-24 keV during one user experiment because the electron energy is fixed for the entire facility.

We strongly recommend not to change the photon energy during your experiment, or at least not more than 1 keV. Larger changes need extensive tuning time of the LINAC and undulators and may lead to a low technical feasibility ranking. Also the x-ray focusing needs to be changed and aligned after each change.

In HXRSS (seeding mode, special mode a), it is not possible to scan the photon energy wider than the SASE bandwidth, i.e. ~30 eV at ~10 keV photon energy

The „special mode b“ two-color has been successfully demonstrated at HED, however interested proposers should contact HED staff with their specific request and HED would catalyze a discussion with experts feeling comfortable to discuss these. We feel confident to offer up to 100 µJ per color and pulse.

Detectors and diagnostics

X-ray area detectors

We offer several Jungfrau detectors (Si chip based, 38x77 mm sensitive area) inside the vacuum of IC1 and in-air outside the chamber. While most modules have square pixels of 75µm pitch, we have also so-called "strixel" modules with rectangular pixels of 25µm x 225 µm for spectroscopy applications. Contact Thomas R. Preston for details.

 

We also offer VAREX detectors as part of the DiPOLE IC2 standard configuration, which are scintilator-based large flat-panel detectors, work at 10 Hz only and at photon energies exceeding 14 keV. They have no single-photon counting capability.

The AGIPD 500K is a Si-based detector with 200µm pixels that can record up to 352 images at a maximum rapetition rate of 4.5 MHz. We use it for DAC XRD measurements.

For details on VAREX and AGIPD, please contact Cornelius Strohm.

 

 

Further information on the camera:

 

https://www.shimadzu.com/an/products/materials-testing/high-speed-video-camera/hyper-vision-hpv-x2/features.html

https://hadlandimaging.com/wp-content/uploads/2019/08/Shimadzu-HPV-X2-FTCMOS2-Sensor.pdf

 

 

X-ray spectrometers

HAPG mosaic von-Hamos Spectrometers

Inside IC1, we offer two von-Hamos HAPG spectrometers for X-ray emission or inelastic X-ray scattering measurements. Please contact Thomas Preston for further details and read: https://doi.org/10.1088/1748-0221/15/11/P11033.

These spectrometers, equipped with Jungfrau detectors and tungsten shielding, have been successfully used for K-line spectroscopy in combination with RELAX shots at I=1021 W/cm².

 

"Dortmund" X-ray emission spectrometer

  • range: 6 keV - 12 keV
  • dispersion: ~0.4 eV/pixel (JF detector)
  • instrumental broadening: ~0.5 - 1 eV
  • Multi-fluorescence spectroscopy e.g.:
    • Si(531) for Fe K beta
    • Si(333) for Fe K alpha
    • Si(444) for Re L alpha (~12 keV)
  • Kaa et al., JSR 30 (4), 822–830 (2023), https://doi.org/10.1107/S1600577523003041
  • Please contact Karen Appel for details.
  • This project was made possible by the BMBF under project 05K19PE2

 

 

Diced Crystal Analyzers for high-resolution spectroscopy

 

We also offer diced crystal analyzers (DCAs) matched to our high-resolution monochromator at 7.49 keV. These allow for meV-resolution inelastic x-ray scattering experiments.
Details and applications are published in 

 

Direct-beam XFEL spectrum analyzers

We currently have means to characterize the spectrum of the XFEL beam itself by the following spectrometers:

  • HIREX-2: this is a convex-bent thin crystal (silicon and diamond) for upstream in the x-ray beam transport, before the distribution mirrors. It is used to tune seeding and monitor the XFEL spectrum  and maintained by the XPD group (Naresh Kujala).
  • A similar spectrometer to HIREX, but located at the end of the HED-HIBEF hutch before the beamstop. It is funded by the French CNRS. Contact Carsten Baehtz for details.
  • A spectrometer based on a divergent beam from a glassy carbon scatterer onto a distant flat crystal. Contact Thomas Preston for details.

 

 

Drivers

We offer these drivers to create an HED state:

  • Isochoric x-ray heating (using XFEL pulse to create plasma)
    • single pulse SASE or HXRSS ("seeded beam")
    • two-color two pulse pump.probe
  • Pump-probe laser (PP)
    • in IC1, standard configuration grazing-incidence X-ray scattering/difraction
  • Diamond Anvil Cells
    • in IC2 (MHz XRD standard configuration)
    • in IC1 (XRD plus K-beta spectroscopy)
  • DiPOLE-100X shock laser 
    • in IC2 (XRD standard configuration) 
    • in IC1 for x-ray spectroscopy (standard configuration)
  • 300 TW relativistic laser RE.LA.X 
    • in IC1, standard configuration X-ray imaging
    • in IC1, standard configuration, SAXS

We encourage to use standard configurations, as you will have a higher chance to get scheduled.

All proposals must be submitted through UPEX (https://in.xfel.eu/upex) after being discussed with instrument scientists.

Interaction chambers at HED-HIBEF

Interaction Chamber IC1

IC1 is a large and flexible chamber and hosts all RELAX and most x-ray only experiments.

  • 4x (vacuum) and 1 in-air JUNGFRAU detectors (gain switching 104) at 10 Hz (no burst mode) for XRD or spectroscopy (pixel pitch 75um, detector size ~ 3.5*7 cm). For details on detectors, please contact Thomas Preston (Thomas.preston@xfel..eu) from EuXFEL HED/detector group.
  • Possibility to mount area detectors or spectrometers on curved rails in vacuum on vertical breadboard
  • Von-Hamos HAPG spectrometers (RoC 50mm and 80mm, crystals available 40um HAPG, 100um HAPG, 200um HOPG)
  • X-ray emission spectroscopy in Von-Hamos geometry
  • High-resolution monochromator and diced analyzers (Si 533) for ~45meV spectroscopy at 7.490 eV
  • stepper-motor based target stage (10x10 cm area) on hexapod and precision rotation stage
  • CRL4 x-ray lens stack for ~µm foci with short focal length

Interaction Chamber IC2

IC2 offers two distinctly different configurations. The entire internal breadboard is exchanged to field two setups:

Diamond Anvil Cell (DAC) setup for precision XRD

  • AGIPD mini-half 4.5 MHz detector
  • Pulsed laser heating for DAC research
  • Dynamic DAC (dDAC)

 

DiPOLE XRD shock setup

  • DiPOLE laser at 2w
  • 2 VAREX flatpanel detectors in IC2 (10 Hz)
  • VISAR

 

Please contact instrument team, e.g. Zuzana Konopkova (DAC), Rachel Husband (DAC), Cornelius Strohm (DAC and shock), or Erik Brambrink (fshock).

Alternating setups in IC2, standard configurations

Users are always welcome to submit regular (non-standard platform) proposals which fit to the instrument capabilities. However, before submitting your proposal, it is mandatory to discuss your proposal with the instrument staff, as not all combinations are technically feasible.

DiPOLE XRD and DAC XRD proposals compete for the same resources, e.g. beamtime at 16.3 GeV electron energy and IC2 target chamber access. Therefore, European XFEL decided to schedule the DiPOLE platform in each second half of a calendar year. Please note that this does not apply to DiPOLE "spectroscopy proposals" at lower photon energies for IC1. For 2026 we will again welcome proposals for both platforms since we schedule the entire year.

 

Pump-Probe (PP) Laser 

Anticipated parameters

PP laser at 800 nm wavelength

  • < 20 or 50 fs duration, close to Fourier-limited bandwidth (going for narrower bandwidth with longer pulse duration is an option)
  • max ~1 mJ at 100 kHz, or down to 10Hz or shot-on-demand
  • higher repetition up to 4.5 MHz with lower pulse energy
  • Second harmonic (400 nm) is available. Conversion efficiency is however low (15-20%) due to the large bandwidth.
  • chirped mode up to ~10 ps duration

PP laser at 1030 nm wavelength

  • Duration: ~ 1 ps compressed “or” ~450 ps uncompressed. Please contact instrument scientists to discuss the possibiliy of pulse durations in between these two values.
  • max ~30 mJ at 100 kHz, or down to 10Hz or shot-on-demand
  • higher repetition up to 4.5 MHz with lower pulse energy
  • second/third harmonic (515/343 nm) are potentially available.

If you plan to use the PP laser, please contact Motoaki Nakatsutsumi  or Rahul S. Venkata

Experiments using Diamond Anvil Cells - DAC platform

Diamond Anvil Cell (DAC) standard configuration

  • IC2 standard DAC setup, 
  • symmetric DAC cell support for users who need cells. User supplied BX90 with adapters.
  • optical observation microscope, streaked pyrometry for x-ray heating.
  • 18-24 keV SASE, max rep rate 4.5 MHz, > 0.5 mJ pulse energy from the undulators (not accounting for beamline transmission)
  • 5-15 micrometer focal spot size (fixed at 5 µm, but effectively larger depending on beam pointing stability)
  • Detectors: AGIPD 500K detector and VAREX flatpanel 
  • Requirement to contact HED instrument team for feasibility check (Zuzana Konopkova, Cornelius Strohm).

AGIPD 500K detector

 

Pulsed laser heating

  • double side laser heating in DACs
  • 2x 100 W NIR lasers in pulse mode or cw mode, pulse duration 10-500 ns, and >1 µs possible
  • temperature determination: time resolved spectral radiometry (SOP) using streakcamera system
  • please contact Zuzana Konopkova for details.

 

Streaked Optical Pyrometry

  • record thermal emission through a spectrometer onto a streak camera
  • available, please contact Zuzana Konopkova for details.

 

Dynamic DAC (dDAC)

MHz XRD set-up for dynamic compression experiments in the diamond anvil cell (dDAC).

This mode is usually coupled to "long train delivery", 352 pulses in 550 µs (special mode "d") due to the limited strain rate of the piezo drive.

  • R.J. Husband et al., JSR 30 (4), 671–685 (2023), https://doi.org/10.1107/S1600577523003910

 

More details

MHz XFEL XRD and modeling of pulsed laser heated DAC:

Dynamic optical spectroscopy and pyrometry (SOP) under optical and x-ray laser

 

DiPOLE 100-X experiments

Standard configuration "XRD" IC2

 

Geometry

  • the quasi-collinear shock geometry (22.5°between shock direction and x-rays), however 90° between laser drive and x-rays may be proposed, but requires a setup change and commissioning time (please account for it in your proposal).
  • DiPOLE100-X laser at 2w, focus on target 
  • available phase plates: 
    • 100 µm (nominal, in reality more like 130 µm) 
    • 180 µm
    • 250 µm 
    • 300 µm (LLNL)
    • 500 µm
    • 1000 µm
  • 2w (green) laser energy: temporal square pulse scales as currently expected: ca. 50 J in 10 ns, ca. 15 J in 2 ns.
  • pulse shaping (other than flattop) on best-effort basis, contained energy has to be evaluated and will be lower than in a square pulse.

 

X-ray diagnostics

  • XRD with VAREX at 18 keV x-ray photon energy, SASE.

 

Optical diagnostics: 

  • VISAR (1 arm 1064nm and 2 arms 532nm) plus 1 SOP arm.

 

Standard configuration "spectroscopy" in IC1

Shock compression experiments with DiPOLE in the IC1 chamber can now be requested.

Two HAPG spectrometers are available which allow to study:

  • Resonant inelastic X-ray scattering (RIXS)
  • X-ray emission spectroscopy (Fe K-beta)
  • Plasmon dispersion w(k)
  • X-ray Raman spectroscopy

Contact the instrument team for details.

 

ReLaX 300-TW laser

Parameters

Details about RELAX can be found in: A. Laso Garcia et al., High Power Laser Science and Engineering (2021) - https://doi.org/10.1017/hpl.2021.47. Further questions about the laser can be directed to Toma Toncian, t.toncian@hzdr.de


RELAX parameters:

  • up to 100 TW  laser beam available at IC1 target chamber. 
  • Laser pulse duration <30 fs (nominal).
  • Energy up to 6 J on target. 
  • Irradiation geometry: 45 deg to X-ray axis and target normal.
  • F/2 focusing optic.
  • Laser wavelength 750-850 nm.
  • Arrival jitter compared to x-rays at IC1 <30 fs RMS.
  • a synchronized optical probe beam with mJ energy can be made available upon request.
  • on shot diagnostic package with NF, FF, WF, pulse duration, arrival time at PAM. 
  • latest laser contrast trace can be measured upon request.
  • Shot-on-demand experiments (other modes upon request).
  • Shot rate will be limited by alignment time, debris issues, and probationary radiological limits.

 

Typical temporal jitter between short-pulse lasers and XFEL

 

ReLaX standard configuration 1: ReLaX + SAXS + PCI + Spectroscopy

This is a configuration in the IC1 chamber, 100 TW ReLaX laser incident on target at 45° w. r. t. XFEL (no normal incidence of laser on target is allowed).

 

X-ray delivery and diagnostics

 

X-ray spectrometers

  • Backward-facing HAPG x-ray spectrometer
  • Forward-facing spectrometer with restrictions of angles and photon energies due to the SAXS setup. Note that the spectroscopy signal may suffer from plasma background, which would require e.g. special shielding.

 

Laser diagnostics (upon agrement with staff prior to proposal submission):

  • EMP, electron, bremsstrahlung and proton diagnostics

 

ReLaX standard configuration 2: ReLaX + sub-µm imaging + Spectroscopy

This is a configuration in the IC1 chamber, the 100 TW ReLaX laser is incident on target at 45° w. r. t. XFEL (no normal incidence of laser on target is allowed). This configuration is NOT compatible with SAXS.

 

X-ray setup

  • X-ray imaging @ 8.15 keV SASE (slightly flexible, minimum 7.5 keV), ca. 1 mJ per pulse, 2.25 MHz maximum rep rate.
  • 1.5-50 µm spot size (X-ray),
  • 5-50 um spot size ReLaX. Note that >10 µm spot by defocusing of off-axis parabola will produce non-homongeneous spatial profile
  • Imaging resolution <1µm

 

X-ray spectrometers

  • Backward-facing HAPG x-ray spectrometer
  • Forward-facing spectrometer with restrictions of angles and photon energies due to the SAXS setup. Note that the spectroscopy signal may suffer from plasma background, which would require e.g. special shielding.

 

Laser diagnostics (upon agrement with staff prior to proposal submission):

  • EMP, electron, bremsstrahlung and proton diagnostics

Standard configuration: PP laser + grazing incidence X-ray small-angle scattering (GISAXS) and diffraction (GID)

 

  • X-ray: 8 – ~10 keV, grazing-incidence up to angle of incidence (AoI) ~ 2°
  • PPL: the laser profile will be elongated in one direction to match the x-ray footprint on the sample  
  • CRL4a: used to achieve a ≤ 1 µm spot size (elongated to ~100 µm depending on the angle of incidence)  
  • Two diffraction (GID) detectors (Jungfrau) available, positioned ~15 cm from the sample (Q coverage 1.5–2 Å⁻¹)  
  • One GISAXS detector (Jungfrau) at 60–70 cm from the sample, with ~6° angular coverage  
  • Samples: well-polished (RMS roughness ≤ 1 nm) samples on thick substrates should be used, cut into pieces ~7 mm wide and up to 95 mm long  
  • A 0.1 Hz repetition rate has been demonstrated; higher rates may be possible but are not guaranteed 
  • Applications: laser ablation and warm dense matter (WDM) studies 

 

 

 

Cryogenic liquid jet target platform IC1

 

The platform features:

  • Vertical jet flow direction
  • Nozzle types: round and slit (size/shape depends on gas type)
  • Gas types: Hydrogen (tested), Methane, Argon and others (not yet comissioned with the setup)
  • Motorized target rotation +/-45 deg (z-axis)
  • High resolution on-shot target imaging (xy-plane)
  • Online target position recognition (see screenshot)
  • Compatible with FSPEC, BSPEC, SAXS, XRD diagnostics in IC1
  • 30x30mm target frame (calibration, pin, ref targets, etc.)
  • High repetition rate shots with ReLax and PP lasers (possible laser parameters are jet type dependent)

Before submitting proposals, please discuss with Sebastian Goede the possible geometries, other x-ray diagnostics, target & laser specs, etc.

Pulsed Magnetic Field (PMF) experiments

 

In the second half of 2024 run, the first community experiment with pulsed magnetic fields at HED-HIBEF was executed. The platform is still in development.

If you are interested to submit proposals for this platform, please contact

Carsten Baehtz (carsten.bahetz@xfel.eu) or

Cornelius Strohm (cornelius.strohm@desy.de)

Frequently Asked Questions - FAQ

Q: What is HIBEF priority access?
A: The HIBEF user consortium is elegible for up to 30% or the available user beamtime for their priority program (this is about 12x 24hrs per half year). The decision on which experiments are included in this priority program is taken my the HIBEF management board after internal discussions and review. For details, please contact the spokesperson of HIBEF, Prof. T. Cowan.

 

Q: How many experiments will be scheduled?
A: For one run (typically a period of 4-5 months), we can schedule between 5 and 12 user experiments. Time to change the setup between those may be 1-2 weeks, but sometimes only 1-2 days. We encourage to use on of our standard configurations (ReLaX, DAC, DiPOLE). Please note that XRD proposals using DAC and DiPOLE in IC2 are usually offered only in alternating semesters only. This will however not be the case for allocation in 2026.

 

Q: What target chambers are available?
A: We offer both interaction chamber 1 (IC) and interaction chamber 2 (IC2). The vacuum in both chambers is oil-free and base operation pressures are around 10-4 mbar (however the chamber can reach lower pressures). Please ask us for our vacuum guidelines.
IC1 offers a rectangular multi-purpose chamber with a breadboard. The sample stack in located in the center, featuring a rotation stage, a large hexapod and a sample scanner.  A vertical breadboard has in-vaccum motorozed rails, where detectors and spectrometers can be mounted. The radius of curvature of these rails points towards the interaction point.
IC2 is a chamber dedicated to precision x-ray diffraction. In IC2, the Diamond Anvil Cell and the shock platform with the DiPOLE laser are possible, but offered in alternating semesters. For DAC experiments, note that the full 1M AGIPD detector is not yet available, however we offer an in-air 500K-pixel AGIPD detector. The DIPOLE laser work together with the VAREX flat-panel detectors, not (!) with AGIPD.

 

Q: I want to use the bunch trains, aka "burst mode" - what repetition rate is available?

European XFEL is usually running with 2.25 MHz repetition rate, but there will be 1 week per run and instrument where European XFEL offers 4.5 MHz (222 ns between pulses).

 

Q: Will there be a bunchtrain-resolved detector (kHz, MHz) available?

Yes - We have implemented an in-air 500K-pixel AGIPD. The development of "burst mode" for the JUNGFRAU detector is ongoing (200 kHz) and is NOT yet available for user operation. Please contact the instrument scientists for more details.


Q: What x-ray photon energies and tunability do you offer?
A: We offer full tunability between 5 and 24 keV with SASE spectrum (0.2% bw). We will have monochromators available (1eV bandwidth 5-18 keV, and 40 meV bw at 7.49 keV). We offer focused x-rays or collimated x-rays with < 2 µrad divergence and few 100 µm diameter. Currently, we have demonstrated pulse energies in SASE2 of 2.5 mJ at < 10 keV, and around 1 mJ at 18 keV. Seeding is available upon request between 7 and 18 keV.

 

Q: Can I bring my own instrumentation (motors, stages, cameras) and will you implement them into the XFEL control system?
A: In general no. We will be still occupied to commision the baseline instrumentation at HED, and we have limited resources to implement additional features. We ask you to use the available equipment. Also, since there are only a few days between two experimental campaigns, there is very little time to work on the mechanical setup. The only possibility is to bring a fully prealigned setup with independent motor controls, which runs stand-alone for your experiment, but this is not perferred as the data is not synchronized with the bunch ID pattern.