The X-ray Pump–Probe instrument at the Linac Coherent Light Source

Systematic understanding and real-time feedback capability for x-ray free electron laser (FEL) accelerator and optical components are critical for scientific experiments and instrument performance. Single-shot wavefront sensing enables characterization of the intensity and local electric field distribution at the sample plane, something that is important for understanding scientific experiments such as nonlinear studies. It can also provide feedback for alignment and tuning of the FEL beam and instrumentation optics, leading to optimal instrument performance and greater operational efficiency. A robust, sensitive, and accurate single-shot wavefront sensor for x-ray FEL beams using single grating Talbot interferometry has been developed. Experiments performed at the Linac Coherent Light Source (LCLS) demonstrate 3σ sensitivity and accuracy, both better than λ∕100, and retrieval of hard x-ray (λ 0.13 nm, E 9.5 keV) wavefronts in 3D. Exhibiting high performance from both unfocused and focused beams, the same setup can be used to systematically study the wavefront from the FEL output, beam transport optics, and endstation focusing optics. This technique can be extended for use with softer and harder x rays with modified grating configurations.

show abstract

“…We tested the performance of this WFS at the x-ray pump-probe (XPP) instrument at LCLS [20]. For the first set of experiments, Fig.…”

Section: Single Grating Wavefront Sensor and Its Performance At Lclsmentioning

confidence: 99%

“…In the pink beam case, a CRL stack with an effective focal length of 3.85 m was inserted to achieve an approximately 1 μm focus at the XPP interaction point [20]. To measure at the first Talbot plane, the grating was placed 1.89 m from the nominal focal plane, and the scintillator was placed 0.48 m from the grating.…”

Section: Research Articlementioning

confidence: 99%

High-accuracy wavefront sensing for x-ray free electron lasers

Liu

Seaberg

Zhu

et al. 2018

Optica

Self Cite

View full text Add to dashboard Cite

show abstract

“…2b. The fluorescence spectra were measured at the XPP instrument [15], with a primary energy of 9 keV, and at SSRL BL2-1 with a primary energy of 7.5 keV, respectively.…”

Section: Performance Of the Prototype Cameramentioning

confidence: 99%

ePix100 camera: Use and applications at LCLS

Carini¹,

Alonso‐Mori²,

Blaj³

et al. 2016

AIP Conference Proceedings

View full text Add to dashboard Cite

Development of speckle-free channel-cut crystal optics using plasma chemical vaporization machining for coherent x-ray applications Review of Scientific Instruments 87, 063118 (2016) Abstract. The ePix100 x-ray camera is a new system designed and built at SLAC for experiments at the Linac Coherent Light Source (LCLS). The camera is the first member of a family of detectors built around a single hardware and software platform, supporting a variety of front-end chips. With a readout speed of 120 Hz, matching the LCLS repetition rate, a noise lower than 80 e-rms and pixels of 50 μm x 50 μm, this camera offers a viable alternative to fast readout, direct conversion, scientific CCDs in imaging mode. The detector, designed for applications such as X-ray Photon Correlation Spectroscopy (XPCS) and wavelength dispersive X-ray Emission Spectroscopy (XES) in the energy range from 2 to 10 keV and above, comprises up to 0.5 Mpixels in a very compact form factor. In this paper, we report the performance of the camera during its first use at LCLS.

show abstract

“…In the first years, XPP provided insights into the dynamics of ferroelectrics (Daranciang et al, 2012), the dynamics of basic chemical processes (Haldrup et al, 2016) and provided basic knowledge of structural dynamics in various materials (Trigo et al, 2013). A recent overview of the XPP instrument describes the instrumentation in detail (Chollet et al, 2015). FemtoMAX is an incoherent source with significantly lower flux than LCLS, but with the aim of being able to carry out a large portion of the solid-state and chemical physics science programmes that today rely on over-subscribed hard X-ray FELs.…”

Section: Introductionmentioning

confidence: 99%

FemtoMAX – an X-ray beamline for structural dynamics at the short-pulse facility of MAX IV

et al. 2018

View full text Add to dashboard Cite

The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100 fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å ). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.

show abstract

The X-ray Pump–Probe instrument at the Linac Coherent Light Source

Cited by 188 publications

References 31 publications

High-accuracy wavefront sensing for x-ray free electron lasers

High-accuracy wavefront sensing for x-ray free electron lasers

ePix100 camera: Use and applications at LCLS

FemtoMAX – an X-ray beamline for structural dynamics at the short-pulse facility of MAX IV

Contact Info

Product

Resources

About