The beamline BL1 delivers non-monochromatic FEL photons and is equipped with KB focusing optics providing a focal spot of ~7 µm x 8 µm (at 13.5 nm; depending on wavelength). The permanent end-station, CAMP, is a multi-purpose instrument that provides large-area, fast-readout pnCCD photon detectors (1 Megapixel, 75 µm pixel size, ~ 8 cm x 8 cm active area), different double-sided velocity map imaging (VMI) and COLTRIMS-style electron-ion spectrometers. A split-and-delay unit for XUV pump - XUV probe experiments at 13.57 nm wavelength in a delay range from from −29 ps to +654 ps was recently added.
After the shutdown in 2024-2025, BL1 will initially not be operable with an optical pump-probe laser. A high-power optical pump-probe laser for FLASH1 beamlines will be built after accomplishing the seeded FEL and its delivery.


DESC multilayer-mirror-based split-and-delay unit

Please have a look at the publication M. Sauppe et al., J. Synchrotron Rad. (2018). 25, 1517-1528 (https://doi.org/10.1107/S1600577518006094) for more information.

Kirkpatrick-Baez (KB) focusing mirrors at BL1

Beam monitors: YAG or MCP based; 2x GMD transparent beam position and pulse energy monitors (one before the gas attenuator and one behind); VLS: variable line space grating spectrometer to measure online the shot-to-shot SASE-FEL spectrum (optimized to reflect the FEL beam to the endstaion in 0th order); gas attenuator & several filters to suppress/enhance harmonics or attenuate the FEL beam; fast shutter to reduce rep. rate down to single pulses; optical alignment laser
Max Flux On Sample
1 * 1014 [ph/s] @ 100 [eV]
Other Optics
4 additional transport mirrors before KB focusing with two different coating (Nickel or Carbon) and a total transmission of ~48% or ~29% for photon energies below and above 250eV.


Focal Length
680 [m]
Spot Size Hor
7 [um]
Spot Size Vert
8 [um]
Endstations or Setup


Long distance optical microscope for in-focus spatial overlap of FEL and optical laser beams using a Ce:YAG screen, as well as for sample positioning (resolution ~10µm)
Double-sided VMI spectrometer for simultaneous electron and ion measurements.
Wide angle scattering using large area, pnCCD photon detectors.
Base Pressure
1 * 10-9 [mbar]
Detectors Available
pnCCD photon detector
VMI spectrometer
Endstation Operative


Sample Type
Amorphous, Gas, Other: nano-particles, single (bio-) particles and large viruses
Mounting Type
User-provided sample injection/mounting required!

pnCCD photon detector

Large area, single photon sensitive, XUV and X-ray pixel detector (CCD, 10Hz)
CAMP can be equipped with two large-area (78 x 74 mm²), single-photon counting 1 Megapixel pnCCD detectors (75 x 75 µm² pixel size), which collect scattered and fluorescent photons with high quantum efficiency and an energy resolution of 40 to 200 eV between <100 eV and 25 keV at a frame read-out rate up to 200 Hz. A variable-sized gap/hole in the center of the first CCD allows the direct FEL beam (and a high-power pump-probe laser, if applicable) to pass through the detector, while the small-angle scattering signal within the area of the hole can be detected on the second CCD, which has a fixed-diameter hole for the direct FEL beam. Both pnCCD detectors can be removed individually if they are not needed in order to provide more flexibility inside the experimental chamber. The typical base pressure with pnCCDs is ~10^-7 to 10^-8 mbar.
Pixel Size
X = 75 [um], Y = 75 [um]
Array Size
X = 1024 [pixel], Y = 1024 [pixel]
Passive or Active (Electronics)
Dynamic Range
1 * 102 [photons/pixel]


Detected Particle

VMI spectrometer

Double-sided velocity map imaging (VMI) spectrometers for simultaneous electron and ion measurement
Optional double-sided electron and ion imaging spectrometers (time-of-flight, velocity map imaging (VMI), and COLTRIMS/‘reaction microscope’ spectrometers) are available to detect ions and/or electrons of up to a few hundred eV kinetic energy within the full 4pi solid angle, while its conical electrodes provide an unrestricted line-of-sight from the interaction region to the pnCCD detectors. The spectrometers use 80mm MCP detectors that can be operated with delay-line anodes for coincident, momentum-resolved single particle detection or with MCP/phosphor screen detectors that are read-out at 10 Hz by CCD cameras.
Time Resolved
Array Size
X = 1300 [pixel], Y = 900 [pixel]
Passive or Active (Electronics)
Output Readout Software
Image readout (at 10Hz) integrated into the FLASH DAQ system


Detected Particle
Benjamin Erk
  • Coherent diffractive imaging
Ion Spectroscopy
  • Ion imaging
  • Mass spectrometry
Photoelectron emission
  • Angular Resolved PES
  • Time-resolved studies
  • UPS
  • XPS
  • Coherent scattering
  • Magnetic scattering
  • Time-resolved scattering
  • Wide angle scattering
  • Atoms, molecules, clusters and gas-phase chemistry
  • Femtochemistry, solid- and liquid-state chemistry
  • Other - Chemistry
  • Physical Chemistry
Life Sciences & Biotech
  • Molecular and cellular biology
  • Other - Life Sciences & Biotech
Material Sciences
  • Other - Material Sciences
  • Atomic & molecular physics
  • Dynamics
  • Other - Physics
  • Quantum electronics & optics
  • Technique Development - Physics
Notkestraße 85
Building 28c (FLASH1 Hall)
22607 Hamburg
control/Data analysis
Control Software Type
  • To control the beamline and the photon diagnostics tools provided by FLASH we have a visualization software called "jddd". The underlying FLASH control system is a DESY specific system called "DOOCS". APIs for python (and Matlab) are existing to allow read and write access for user scripts to DOOCS controlled devices.
Data Output Type
  • There are two different approaches possible. The "online" reading of the data stream by python (or Matlab) with the provided API or the "semi online" and offline data analysis using HDF5 files containing user data and all relevant FEL parameters. See FLASH documentation for details.
Data Output Format
  • HDF5
Softwares For Data Analysis
  • A data base for python (and Matlab) scripts is currently build up.
Equipment That Can Be Brought By The User
The instrument offers up to 4x CF250 ports centered on the FEL focus. This allows the user groups to bring various types of target injectors/holders and specific (additional) detectors.