The new FL23 pulse-length preserving double-grating monochromator beamline is an open-port variable micro-focus beamline covering the FEL wavelength range of 1.2 – 20 nm (including FEL harmonics). The double grating monochromator design of FL23 will provide a narrow spectral bandwidth of the FLASH2 photon pulses while preserving the ultrashort (FEL) pulse duration of less than 50 fs. A Kirkpatrick-Baez mirror system employing bendable mirrors focuses the monochromatized radiation down to approx. 5 x 5 um beam size at the target, independent of the monochromator slit. Due to a moveable exit arm, the monochromator can be used in double- or single-grating configuration. The latter allows higher throughput and is particularly interesting when using harmonics at short wavelengths.
|
Photon Beam Parameter (Baseline Configuration) |
|
|---|---|
|
Photon energy |
3.5 – 20 nm (down to 1.2 nm including harmonics) |
|
Flux@sample |
1010 photons |
|
Focus size |
5 um x 5 um FWHM (variable) |
|
Pulse duration |
<100 fs FWHM |
|
Resolving power |
Resolving power > 2000 |
|
Configurations |
Single (high transmission) & double grating (pulse length preserving) |
CONTACT:
|
|||||||
References:
[1] L.Poletto et al., Double-grating monochromatic beamline with ultrafast response for FLASH2 at DESY, J. Synchrotron Rad. 25 (1), 131 - 137 (2018);
https://doi.org/10.1107/S1600577517013777
[2] M. Ruiz-Lopez et al., Wavefront-propagation simulations supporting the design of a time-delay compensating monochromator beamline at FLASH2, J. Synchrotron Rad. 26 (3), 899 - 905 (2019); https://doi.org/10.1107/S160057751900345X
