Predicting the coherent X-ray wavefront focal properties at the Linac Coherent Light Source (LCLS) X-ray free electron laser

Abstract

The first X-ray free electron laser (XFEL) at keV energies will be the Linac Coherent Light Source (LCLS), located at the SLAC National Accelerator Laboratory. Scheduled to begin operation in 2009, this first-of-a-kind X-ray source will produce ultra-short X-ray pulses of unprecedented brightness in the 0.8 to 8 keV first harmonic photon energy regime. Much effort has been invested in predicting and modeling the XFEL photon source properties at the undulator exit; however, as most LCLS experiments are ultimately dependent on the beam focal spot properties it is equally as important to understand the XFEL beam at the endstations where the experiments are performed. Here, we use newly available precision surface metrology data from actual LCLS mirrors combined with a scalar diffraction model to predict the LCLS beam properties in the experiment chambers.

Resonance-enhanced multiple ionization of krypton at an x-ray free-electron laser

“…In this measurement campaign the CAMP setup was used as an ion time-of-flight and imaging spectrometer, and the pnCCD photon detectors were not installed [16]. After passing through a set of photoluminescence-based pulse-energy detectors [17] and an attenuation chamber used to adjust the beam energy for intensity-dependent measurement upstream of the AMO beamline, the LCLS beam (120 Hz repetition rate, 1.5 and 2 keV photon energies) was reflected on three steering mirrors, and focused inside the CAMP main chamber (background pressure ≈2 × 10 10 mbar) by a pair of two dynamically bent grazing-incidence mirrors in Kirkpatrick-Baez geometry [18]. The overall transmission of the beamline and the focal spot dimensions will be discussed below.…”

Much Ado about Microbunching: Coherent Bunching in High Brightness Electron Beams

“…We compare the measured and expected values in Fig. 5.3 [72]. The discrepancy between the curves is likely the result of a change in the angle of the mirrors, which must move to redirect the beam to the far experimental hall.…”

X-ray metrology and performance of a 45-cm long x-ray deformable mirror

“…17 However, in most cases of interest to us Talbot effects are present. 18 In particular, the Talbot length can be comparable to the length of the x-ray optic in question.…”