Advanced analysis and modelling methods has been an essential part of X-ray optics advances and X-ray techniques development at synchrotron light sources. These methods not only help researchers develop designs of X-ray sources and beamlines, diagnose and identify problems and issues in operations, but also enable advanced modelling and simulations of novel X-ray optics and experiments. Recent development rends in diffraction-limited sources and in coherence applications further illustrate the community interests and increased needs in advanced wavefront-based analysis and modelling capabilities. This presentation will provide an overview of this growing area of X-ray optics and techniques and its impact on synchrotron science in general.

X-ray free electron lasers and next generation synchrotron radiation facilities will use larger and faster x-ray imaging detectors. We would like to introduce the present status and future perspective of the data acquisition and handling system, including the development program of the new generation image sensor, ongoing at SACLA/SPring-8 facilities.

SPECTRA is a computer software to calculate characteristics of synchrotron radiation (SR) emitted from various SR sources including exotic ones. Calculations of radiation from an arbitrary magnetic field distribution are also available. Parameters on the electron beam and the SR source can be edited completely in graphical user interfaces (GUIs) and it is possible to show the calculation result graphically. In this talk, recent progress of SPECTRA is presented including a new function of coherent mode decomposition based on a Wigner function representation.

The presentation will include an overview of main functions of the “Synchrotron Radiation Workshop” (SRW) code, dedicated to calculation of different types of synchrotron radiation, and simulation of propagation of fully-coherent radiation wavefronts, partially-coherent radiation by a finite-emittance electron beam of a storage ring source, and time-/frequency-dependent radiation pulses of a free-electron laser, through X-ray optical elements of a beamline. Applications of SRW in the areas of development of new beamlines, as well as commissioning of and performance benchmarking of insertion devices and individual X-ray optical elements of existing beamlines at the National Synchrotron Light Source II will be described.

Xrt is a python-based software library for beamline simulation and analysis in x-ray regime. We provide classes for many beamline elements, propagation engine in ray and wave approximations, and high quality visualization capabilities. Support for GPGPU calculations not only allowed us to speed up existing ray tracing routines but to qualitatively extend the limits of the underlying theoretical models. Sources: increased integration precision at high magnetic fields and high energies, Optics: ability to calculate the diffraction efficiency for gratings and zone plates (Kirchhoff integral theorem), Materials: reflectivity curves of bent crystals by numeric solution of the Takagi-Taupin equations.

The raytrace program RAY developed and continuously upgraded at BESSY since the 1980th is a well-known versatile synchrotron radiation simulation tool, well established since many years with comparable capabilities like the widely used SHADOW-program. Recently a comfortable and powerful graphical user interface RAY-UI has been added, which makes it an attractive and easy-to-use program for every-day use. Special helpful features have been added here like the mono-capillary optics and instantaneous calculation of mirror reflectivities and grating efficiencies of the central beam. A built-in DO-loop helps optimizing certain features such as focal spot or energy resolution as function of e.g. slope errors.

In the next few years most of the major synchrotron radiation facilities around the world will upgrade to 4th generation Diffraction Limited Storage Rings. This represents a huge challenge for all the Optics physicists responsible of designing and calculating new optics. The OASYS suite drives several simulation tools and provides interoperability within the same software environment. OASYS has been successfully used and validated for the conceptual design of several systems of the ESRF and Elettra-Sincrotrone Trieste upgrades.

We present the new features included in McXtrace release 1.4. McXtrace is an open source ray-tracing package designed for simulating X-ray experiments. Among the new features: 1. A set of sources including Wiggler, and Undulator. 2. Flat & bent Bragg-monochromator crystal components. 4. Full-size mode of DanMAX at MAX-IV. 5. Full-size model of FXE at XFEL. 6. SAS-view based SAXS-sample components. 7. A particle list output interface file-format (MCPL) to enable interfacing with e.g. SimEX and MCNP6. 8. Polycrystal model We show examples of these new features, and how they may be utilized in beamline design as for DanMAX.

We will show the application of X-ray simulations at Linear Coherent Light Source LCLS at National Accelerator Laboratory SLAC. The talk will cover characterization of properties of simulated XFEL radiation such as coherence, source shape, divergence and longitudinal location inside the undulator. We will show how the X-ray simulations are used for minimizing the effect of thermal distortions on focusing of the LCLS II X-ray beams by 1 meter long Kirkpatrick-Baez mirrors and for determining damage threshold for diffraction gratings. Time dependent X-ray simulations of the LCLS radiation passing through the seeding monochromator will be also presented.

The European X-ray Free Electron Laser (XFEL) is a high repetition rate source that will deliver the most powerful hard X-ray short pulses in the world, up to 1e14 photons per 100 fs pulse. In the talk we will present the up-to-date status of the EuXFEL X-ray optics in the beam transport system and at specific experimental stations. We will also give a thorough analysis of awaited beam parameters, calculated from the metrology data for the real optics components.

The upgrade of the Advanced Photon Source (APS) to a Multi-Bend Achromat (MBA) will increase the brightness of the APS by between two and three orders of magnitude. The upgrade project includes approximately eight feature beamlines that will take full advantages of the new machine. Many of the existing beamlines will be upgraded to profit from this significant machine enhancement. Optics simulations are essential in the design and optimization of the new and existing beamlines. In this presentation the simulation tools used and developed at APS, ranging from analytical to numerical methods, are summarized. Three general optical layouts are compared in terms of their coherence control and focusing capabilities. The concept of zoom optics, where two sets of focusing elements (e.g., CRLs and KB mirrors) are used to provide variable beam sizes at a fixed focal plane, is described in detail. Finally, simulation studies of a few APS upgrade beamlines are presented.

The soft X-ray beamline IPÊ is one of the first phase SIRIUS beamlines at the LNLS, Brazil. Divided into two branches, IPÊ is designed to perform ambient pressure X-ray photo-electron spectroscopy (AP-XPS) and high resolution resonant inelastic X-ray scattering (RIXS). Resolution of the PGM and thermal deformation effects define the boundary conditions of the optical concept and the simulations of the IPÊ beamline. We compare simulations performed by geometrical ray-tracing (SHADOW) and wavefront propagation (SRW) and show that wavefront diffraction effects (apertures, optical surface error profiles) does not significantly change the beam spot size and shape.

X-ray echo spectroscopy is a recently proposed inelastic x-ray scattering (IXS) technique, a space- domain counterpart of neutron spin-echo. X-ray echo spectroscopy involves imaging of the IXS spectra without requiring x-ray monochromtization. Due to this, the echo-type IXS spectrometers have a potential to simultaneously provide dramatically increased signal strength, reduced measurement times, and higher resolution compared to the traditional scanning-type IXS spectrometers. Here we develop further the theory of the x-ray echo spectrometers initially presented in [1] with an emphasis on questions of practical importance, which could help to design and assess feasibility and performance of the echo spectrometers such as: echo spectrometers tolerances, tuning up the refocusing condition, effective beamsize on the sample, spectral window of imaging and scanning range, the impact of the secondary source size on the spectral resolution, etc. Examples of optical designs of the echo spectrometers with an 1-meV and 0.1-meV resolution will be presented as well. [1] Yuri Shvyd’ko, Phys. Rev. Lett. 116, 080801 (2016).

The mutual optical intensity (MOI) is a four-dimensional coherence function and contains the full coherence information of the beam. The propagation of mutual optical intensity through a soft x-ray beamline is analyzed with a new developed model naming MOI. The MOI model is based on statistics optics. The wavefront is separated into many elements and every element is assumed to has full coherence and constant complex amplitude, which is reasonable if the dimension of element is much smaller than the coherent length and beam spot size. The propagation of MOI for every element can be analytically solved with Fraunhofer or Fresnel approximations. The total MOI propagation through free space can be obtained by summing the contribution of all elements. Local stationary phase approximation is implemented to simulate MOI propagating through ideal mirrors and gratings. The MOI model provides not only intensity profile, but also wavefront and coherence information of the beam. These advantages make MOI model a useful tool for beamline design and optimization. The nano-ARPES beamline at SSRF is analyzed using the MOI model. A zone plate is used to focus the beam. The intensity profile and local coherence at the zone plate are acquired. The horizontal coherence is much worse than the vertical one. By cutting the horizontal beam with the exit slit the horizontal coherence can be improved but at the flux loss. The quantitative analysis on the coherence improvement and flux loss at different exit slit size are obtained with the MOI model.

In this work, the PENELOPE code was used to simulate a thermionic X-ray source in a fast, reliable and flexible way. The emerging photon energy spectrum and spatial distribution are reproduced in a virtual source for subsequent simulations without the computationally expensive burden of repeatedly recreating electron interactions in the tungsten anode. This efficiently aids the characterization and development of coded apertures and pinholes in this security application. The process is validated experimentally with a Cadmium Telluride detector and through comparison to the SpekCalc code.

The optimum thickness and aperture diameter of a pinhole mask for use in backscatter imaging were determined by a PENELOPE simulation. The mask thickness must be sufficient to prevent the leakage through the mask materials, the pinhole aperture wide enough for maximising the field of view. To generate the image, the integrated energy was calculated through MATLAB from the phase-space file to correlate the detected energy and photon positions per pixel. For each mask material contrast, signal to background ratio, spatial resolution and collimation effect were calculated as a function of the thickness and the aperture.

Synchrotron Radiation Workshop (SRW) is a powerful synchrotron simulation tool and has been widely used at synchrotron facilities all over the world. During the last decade, many types of x-ray wavefront sensors has been developed and used. In this work, we will present our recent effort on the development of at-wavelength metrology simulation based on SRW mainly focused on the Hartmann Wavefront Sensor (HWS). Various conditions have been studied to verify that the simulated HWS is performing as expected in terms of accuracy. This at-wavelength metrology simulation tool is then used to align KB mirrors by minimizing the wavefront aberrations. We will present our optimization process to perform an ‘in situ’ alignment using conditions as close as possible to the real experiments (KB mirrors with different levels of figure errors or different misalignment geometry). Present status of this simulation tools will be presented and future foreseen extensions will be discussed, like Grating Shearing Interferometry (GSI) and the possibility to use Transport of Intensity Equation (TIE).

Synchrotron light sources provide X-ray, UV and infrared beams for scientific research. State-of-the-art facilities like NSLS-II produce partially-coherent X-ray beams that enable more sophisticated X-ray optics. We present a GUI for X-ray optics and electron beam dynamics. SRW is used to simulate the generation and subsequent transport of coherent and partially-coherent radiation beams through optical beamlines. We are implementing support for Shadow3 to simulate incoherent radiation. Electron beam dynamics in the storage ring is simulated with the Pelegant code. Examples will be presented and the cloud computing framework Sirepo will be described.

High-accuracy physical optics calculations methods used in the “Synchrotron Radiation Workshop” (SRW) allow for multiple applications of this code in different areas, covering development, commissioning, diagnostics and operation of instruments at light source facilities. This presentation will focus on applications of SRW for determining of important physical characteristics of micro-spectroscopy and coherent scattering beamlines, and on simulation of experiments at these beamlines. Besides the examples of forward-simulation of user experiments, new developments in the SRW code, facilitating solution of the corresponding inverse problems, will be described.

With the increment of Free Electron Laser sources, the hard x-ray optics community must deal with high coherence and ultra-short femtosecond photon pulses. In particular the dynamical diffraction effects that appear in the monochromators based on perfect crystals where multiple scattering effects are involved need a better understanding. For this propose we present a study based on wave optics modeling the propagation of different FEL SASE pulses along perfect crystals in Laue and Bragg geometry, using SRW software. Different thicknesses (between 30 and 100 um) have been studied for two different photon energies 8 KeV and 12 KeV.

A recently advanced concept of an X-ray echo spectrometer allows to overcome limitations of spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) instruments [1]. The spectrometer illuminates a sample with a spatially expanded beam due to energy dispersion of its monochromator. After the sample, the spectrometer analyzer recombines the beam into an image in a detector plane. The enhanced strength of the spectrometer signal allows to speed up the acquisition process and obtain the IXS spectrum with a very high energy resolution. The design of the echo spectrometer is based on a combination of crystal and focusing optics. The spectrometer analyzer requires an X-ray focusing optics with a high numerical aperture which is capable to collect radiation scattered by the sample into a wide solid angle. The required numerical aperture can be achieved with a graded multilayer mirror. To collect the scattered intensity from a solid angle, we considered the mirrors with a single reflection 2D parabolic shape. We simulated the images and investigated the performance of the echo spectrometer with the above mentioned mirrors using numerical computations in the SRW software package.

We report on the results of the advanced commissioning of the Soft Matter Interfaces (SMI) beamline, a long energy range canted in-vacuum undulator (IVU) beamline at NSLS-II. We compare the complete beamline simulation results performed with SRW software and the beam parameters measured during the technical and scientific commissioning. In particular, we will present the outcome of the recent IVU optimization (spectrum-based alignment resulted in a considerable increase of flux at beamline), bimorph horizontal and vertical focusing mirror tuning and profile optimization, as well as the commissioning of the microfocusing CRL transfocator.

Geometrical optics and physical optics simulations are two methods for modelling the transport of X-rays through optical systems. With reductions in source emittance at modern X-ray storage rings, there are greater demands placed on X-ray optical elements to minimize distortion of the X-ray wavefront. We have related the perturbation of the wavefront following reflection from elliptically profiled X-ray mirrors to the figure error of the mirror surface. We show the results of geometrical and physical optics simulations of mirrors whose surface figure had been measured by nanometer optical metrology. Simulation results are compared with measurements from the Diamond Test Beamline.

We continue to develop MOI method to analyze the mutual optical intensity (MOI) propagation through non-ideal optics. Local stationary phase approximation is implemented to calculate the MOI propagating through a non-ideal mirror. The intensity profile, the wavefront and the global coherence degree can be get from the MOI. The results indicate that the figure error with low spatial frequency generates oscillations, redistributes coherence property and damages the wavefront on the image plane, but does not change the global coherence degree. Limitation on the beam size will increase the coherence, which can be quantitatively analyzed by global coherence degree from MOI.

It is important to perform in-situ metrology at the optics’ operating wavelength (‘at-wavelength’ metrology) to optimize the performance of X-ray optics and correct and minimize the collective distortions of upstream beamline optics. The method based on speckle scanning technique is the most promising as we have demonstrated that the angular sensitivity for measuring the slope error of an optical surface can reach accuracy in the range of two nanoradians. The recent development of the speckle-based at-wavelength metrology technique implemented at the Diamond will be presented. Representative examples of the application of the speckle-based technique will also be given.

The design, evaluation and fabrication of high performance x-ray optical systems requires sophisticated and reliable information about the surface topography of optical elements. The fabrication of these custom optics is extremely expensive, mostly due to the extensive metrology used in fabrication. We discuss more efficient metrology through comprehensive statistical analysis of a compact volume of data. A new statistical model called Invertible Time Invariant Linear Filter (InTILF) is developed providing compact description of the surface. The description captures faint patterns and serves as a quality metric and feedback to polishing processes. Supported by NASA SBIR NNX16CM09C and the USDOE AC02-05CH11231.

In the past two decades, there has been a rapid development in our ability to control, manipulate and focus x rays by refractive optics. The emergence of x-ray free electron lasers and diffraction-limited synchrotron radiation sources has increased demands on coherence compatible optics, where refractive lenses as in-line optics have obvious advantages. In addition, the past few years have been witness to significant advances in the development of new coherent techniques based on refractive optics: x-ray microscopy, diffraction imaging and interferometry. Details of these developments are discussed.

Hard x-ray beams can be focused using refractive lenses, but depending on energy, a large number $N$ of individual lenses stacked in a row is needed. Such a stack can be either composed of single lenses in cartridges, or lithographically fabricated lenses in a row. With $N$ in the three-digit regime, the question arises which tolerances on lens alignment and shape have to be met not to disturb the focus. Here we use analytical and numerical calculations based on a Zernike polynomial expansion to give such error bounds for typical set-ups.

We present a generic software platform for the simulations of experiments at modern light sources, e.g. free electron lasers, synchrotrons, and optical laser facilities. In our complete start--to--end simulations, we track the radiation from the source through the beam transport optics to the sample under investigation, the photon-matter interaction with the sample, and detection of scattered or transmitted photons in a detector. In the talk, we outline the concept and ideas behind the simulation platform and present novel results from its application to study single particle imaging at the European X-ray Free Electron Laser.

The presentation will showcase the application of fully- and partially-coherent synchrotron radiation wavefront propagation simulation functions, implemented in the "Synchrotron Radiation Workshop" (SRW) computer code, to create a ‘virtual beamline’, mimicking the Coherent Hard X-ray (CHX) scattering beamline at NSLS-II. Simulations of key performance parameters will be compared to measurements obtained during beamline commissioning, and will include the spectral flux of the undulator source, the degree of transverse coherence, focal spot sizes and simulated and measured coherent scattering patterns.

With the progress of achieving diffraction-limited X-ray focus, ptychography offers a unique and powerful tool to provide quantitative reconstruction of the complex-valued wavefront of a focused beam. Propagation of the reconstructed wavefront essentially describes complete performance characterization of the optics. We will present the accumulated efforts at NSLS-II on exploring the capability of ptychography to quantify focusing performance of a variety of hard X-ray optics, including K-B mirrors, zone plates, multilayer Laue lenses [1-3]. Presentation will also elaborate on our recent development of monolithically bonded MLLs as a signal optical component for scanning probe microscope applications [4,5]. References: [1] X. Huang, et al., “Quantitative X-ray wavefront measurements of Fresnel zone plate and K-B mirrors using phase retrieval”, Optics Express, 20, 24038-24048 (2012). [2] X. Huang, et al., “11 nm hard X-ray focus from a large-aperture multilayer Laue lens”, Scientific Reports, 3, 3562 (2013). [3] X. Huang, et al., “Achieving hard X-ray nanofocusing using a wedged multilayer Laue lens”, Optics Express, 23, 12496-12507 (2015). [4] E. Nazaretski, et al., “Development and characterization of monolithic multilayer Laue lens nanofocusing optics"”, Applied Physics Letters, 108, 261102 (2016). [5] X. Huang, et al., “Hard x-ray scanning imaging achieved with bonded multilayer Laue lenses”, submitted, (2017).

In spectral X-ray CT, scattered radiation plays an important role in the accurate detection of the object’s properties. Using energy-resolving photon-counting detectors, we can analyze the energy distribution of the scattered contribution, which is fundamental to establish methods to correct it. We develop a Monte Carlo spectral CT simulation tool, to predict the impact of scattered radiation at different energy ranges using different collimations of a fan-beam geometry. Simulations are validated by experiments using novel spectral CdTe detectors. The scatter distribution is found to shift towards lower energies. We found a good match between simulations and experiments.

"Sirepo" is an open source cloud-based distributed software framework which provides a user-friendly web-interface for scientific codes such as Synchrotron Radiation Workshop (SRW, a physical optics code). In the present work, we will discuss the most important features of Sirepo/SRW interface with emphasis on their use for commissioning of beamlines and simulation of experiments at NSLS-II. Material properties of crystals, compound refractive lenses, and some other optical elements are dynamically obtained from the databases publicly available at ANL and LBL. In collaboration with the CFN of BNL, a library of samples for coherent scattering experiments has been implemented in SRW.

We introduce OASYS (ORange SYnchrotron Suite), a new graphical environment for simulating X-ray virtual experiments. It provides not only a powerful graphical interface easy and intuitive to use, but allows high flexibility and rapidity for interactive simulations by integrating existing state-of-the-art calculation engines. OASYS integrates different simulation strategies via the implementation of adequate simulation tools for X-ray Optics (e.g. wave optics and ray tracing packages). Python has been chosen as main programming language, and Orange as the high level workflow environment.