This PFD file contains the front matter associated with SPIE Proceedings Volume 11493, including the Title Page, Copyright information and Table of Contents.

Since 2013, OASYS (OrAnge SYnchrotron Suite) has been developed as a versatile, user-friendly and open-source graphical environment for modeling x-ray sources, optical systems, and experiments. Its concept stems from the need of modern software tools to satisfy the demand of performing more and more complex analysis and design of optical systems for 4th generation synchrotron radiation and FEL facilities. The ultimate purpose of OASYS is to integrate in a synergetic way the most powerful calculation engines available to perform virtual experiments in a synchrotron beamline. For x-ray Optics, OASYS integrates different simulation strategies via the implementation of adequate simulation tools (e.g., ray tracing and wave optics packages), which communicate by sending and receiving encapsulated data. The OASYS suite has been extensively used in the optical design process for the APS-U project, and several new tools have been created to perform advanced calculations needed by the design of feature beamlines and to provide accurate specifications for the procurement of the optics.

The upgrade of the Advanced Light Source at Lawrence Berkeley National Lab to a Diffraction-Limited Storage Ring (DLSR) will feature four new and upgraded beamlines, designed to take full advantage of the coherence and high brightness of the insertion device source operating mostly in the soft x-ray regime (100–2000 eV). The round and highly coherent beam drives specific design choices for the photon transport optics and monochromator, and technical challenges in terms of performances, optical tolerances and stability. We have used the simulation tools Shadow (for raytracing) or SRW (wavefront propagation), and their implementation in OASYS and Sirepo to refine tolerance specifications, using their scripting capabilities and new add-ons to perform a comprehensive beamline analysis and confirm that specifications matched our performance requirements, taking into account partial coherence and issues related to heatload.

Cylindrical mirrors with sagittal curvature are known for non-ideal focusing due to strong aberrations. However, the small emittance of undulator sources at new upcoming fourth-generation synchrotrons causes the footprint of the beam on a sagittal cylinder to be small enough to permit almost aberration-free focusing. The use of side deflecting sagittal cylinders in the optical design of synchrotron beamlines brings advantages to the beam performance: a) it improves stability, because horizontal plane is less a effected by ground vibrations, b) it keeps the beam height with respect to the floor, c) the beam is less sensitive to slope errors in the sagittal plane. Furthermore, a sagittal cylinder in combination with a meridional cylinder or ellipse allows the change of focal spot size and position. In this work, we present the optical scheme of three beamlines including sagittal cylinders for the fourth-generation synchrotron SIRIUS. In MANACA beamline (protein crystallography) a sagittal cylinder and a meridional ellipse face each other in the horizontal plane. By changing the incidence angle of both mirrors in the same direction beam size at sample can be changed from 10 to 100 μm. In SAGUI beamline (SAXS and XRD) both mirrors face the same direction. Changing the incidence angle in opposite direction enables to change the focus position by tens of meters. In CATERETE beamline (Coherent Diffraction Imaging) the two mirrors face each other to create a highly coherent plane wave with a focal spot of 40 μm. We compare the performance of each beamline with their ideal optics counterpart, using wave propagation simulations (SRW).

At the National Synchrotron Light Source II, a beamline has been designed that aims to meet the needs of general CDI experiments at x-ray energies between 5 and 15 keV, where access to nanoscale information can be provided in “full-field” images of micron-sized particles in Bragg- and forward-scattering geometries. Here, we present the optical design underlying the proposed beamline, which delivers a variably-sized focal spot in the micron range with independently vari

We performed fully- and partially-coherent synchrotron emission and propagation simulations with the "Synchrotron Radiation Workshop" computer code to analyze the performance of two soft X-ray beamlines under development at the National Synchrotron Light Source II: Soft X-ray Nanoprobe (SXN), and Angle-Resolved Photoemission Spectroscopy (ARPES) and Resonant Inelastic X-ray Scattering (RIXS) Imaging (ARI). The SXN beamline intends to provide high flux and high spatial resolution coherent soft X-ray imaging capabilities using both zone plate and lensless coherent imaging techniques. The ARI beamline aims to perform high flux ARPES and RIXS experiments with a focal spot size at the sample approaching 100 nm using highly-demagnifying mirrors in Kirkpatrick-Baez geometry. To accurately calculate the resolution and the degree of X-ray coherence provided by the two state-of-the-art beamlines, partial coherence effects are required to be taken into account in wave optics simulations for these two beamlines. In this talk, beamline performance parameters such as spot size, degree of coherence, flux, and energy resolution at the sample are presented. The effects of mirror surface slope errors on beamline performance were studied and some suggestions for further optimization are discussed.

Simulations were carried out to study spatial coherence properties of the 4th generation high-energy storage rings based on the previous work [Khubbitdinov et al., JSR (2019)]. It aimed to study special effects, namely an effect of the detuning from the undulator resonance photon energy and energy spread effects of the electron beam in a low-emittance storage ring. These simulations were performed with the XRayTracer (XRT) software package [Klementiev & Chernikov, SPIE 9209 (2014)] and compared with the results of analytical calculations [Geloni et al., JSR (2018)]. The simulations were done in the wide range of photon energies for different electron beam energy spread values and compared to the simulations performed for the detuned photon energy from resonant. The analysis showed that the effect of detuning in combination with the electron beam energy spread significantly reduce coherence properties of the photon beam in a low emittance storage ring sources.

The mutual optical intensity (MOI) package is developed to simulate the mutual optical intensity propagation through beamline and is available online at www.moixray.cn. In this paper we describe the basic principles of the MOI package. The propagation of the mutual optical intensity is numerically carried out by dividing the wave plane into many small elements to meet the requirements of the Fraunhofer or the Fresnel approximations. From the mutual optical intensity, the intensity, the phase distribution and the coherence between any two points in a wave plane can be extracted. The in-plane wave vector distribution in the wave plane of partially coherent beam can be obtained by considering the phase distribution inside each element. The consideration of the in-plane wave vector provides both higher accuracy and higher efficiency, which is very important to the future development of the 2D MOI code. We demonstrate applications of the MOI package on propagation simulations of partially coherent beams in different optical setup, including the propagation through an elliptically cylinder mirror and a parabolically cylinder mirror. The dependence of the in-plane wavevector on the beam coherence is analyzed. Clear  shifts are seen in the in-plane wavevector profile and disappear with decreasing coherence. The knowledge of the in-plane wave vector gives detailed analysis of the beam wavefront. The calculation efficiency depends on the number of elements. The calculation speed for the mutual optical intensity propagation with 1000 elements through one optics is about 2.5 seconds.

We present two main developments within the ray tracing package McXtrace in the recent timespan; The Union concept for building complex sample geometries which may also include sample environments, and the next generation code generator (nicknamed 3.0) which includes the option for GPU-acceleration through the OpenACC programming standard. Union is a concept which allows beamline simulation users to define enclosed regions in which the regular sequential nature of McXtrace simulation is replaced by a scattering network. Within the network any object can scatter towards any other object. Through a pre-analysis of the scattering the this may be done without excessive computational effort - i.e. it is still practical on a standard desktop computer without high-end specs. We will discuss our result results with this concept and how it can be used to, for instance, assess background contributions. Using the OpenACC programming paradigm, the simulation code generated by the new code generator, may now harness the power of novel GPU-cards for faster ray tracing, with fairly non-invasive changes to the user facing code. We will present results on where GPUs may be benefited from and what the user is required to do, in order to enjoy significant speed-ups.

In this work, we report the advances in the development of WISER. WISER is a wave optics-based simulation library targeted at the simulation of the focusing performance of grazing X-Ray optics systems, which accounts for the metrological data of figure error and roughness power spectral density. First presented in 2016 (phase-I), WISER inherits and expands the mathematical concepts of its ancestor, WISE, originally conceived for X-Ray telescopes and then applied to free electron lasers. Thanks to its flexible framework, WISER easily allowed to simulate multi-element systems, as synchrotron and free electron laser beamlines. In phase-II (2020), WISER is further improved and it is delivered as fully integrable with OASYS, the graphical canvas gathering the mostly used X-Ray computation tools. In the following, we will illustrate the architecture of the library and present some examples of its applications.

We describe a reduced model approach to x-ray transport down synchrotron radiation beamlines. The method uses a ray tracing code for computation of a transfer matrix for sections including drift spaces and focusing elements separated by physical apertures. The transport matrix along the beamline is analyzed analogously to charged particle beam optics. For coherent radiation, the wavefront is propagated by the transport matrix via linear canonical transformation. For the partially coherent case, the matrix can be applied directly to the Wigner function. We apply this method to a beamline section comprised of a KB focusing system and compare results between Synchrotron Radiation Workshop and SHADOW. Machine learning methods are also used for 2-D automated alignment. Plans for use of the reduced model within a beamline control system and more advanced used of machine learning methods for automation and reconfiguration are discussed.

The rapid development of new-generation synchrotron facilities with excellent coherence demands more accurate evaluation of beamline performance. A perturbation theory based on wave optics is proposed in this work to describe the effect of imperfections on the performance of x-ray optical elements. It shows that the perturbed performance of the non-ideal optical element could be derived from the perfect performance of the ideal optic through a convolution operation. The semi-analytical approach proposed here provides a new way to improve the simulation efficiency for imperfect optical elements. The finite aperture effect on diffraction-limited optics and focal shape distortion by surface height error are treated to show the application of the proposed method.

A photoelectron gun cavity is an electron source that every Energy Recovery Linac (ERL) requires. Its characteristics and precision determine the capabilities and performance of the ERL. Calibration of the electron gun is a crucial part of its initial setup, which requires a lot of time and experience. We present the first steps towards a tool that guides the electron gun operator, which knobs to turn in which position to achieve the desired properties. In this report, we determine the - typically difficult to identify - offsets between the simulation and the real-world device. We accomplish this by using machine learning and a global optimization algorithm.

The method of the Coherent Mode Decomposition (CMD) is applied to numerical wave propagation calculations for partially-coherent X-rays, using the Fourier optics and compatible methods. Its CPU and memory efficiency is discussed in various cases of the wavefront at the source and the beam waist. With the absence of the quadratic phase terms, the required sampling density of the electric fields is effectively reduced. The problem size is thus moderate and the method is feasible to be implemented on a single-node CPU server. In other cases, the same argument holds with proper treatments of the quadratic phase terms. Tests on CMD and the modes propagation are done for the case of the Coherent Hard X-ray beamline of the National Synchrotron Light Source II, using the Synchrotron Radiation Workshop software. We observe a few hundred or less dominant decomposed modes that resemble the electric fields converge to the wavefront intensity at a high accuracy of over 99%.

The “Synchrotron Radiation Workshop” (SRW) computer code is extensively used for the development of insertion devices (IDs) and X-ray beamlines at the National Synchrotron Light Source II and at other light source facilities. Among frequently used types of SRW calculations are the calculations of spontaneous emission from an ID in a storage ring, physical optics based simulations of propagation of this partially-coherent radiation through a beamline, and the simulations of propagation of 3D time-dependent radiation pulses through instruments of X-ray Free-Electron Lasers (XFELs). The two types of radiation propagation calculations are CPU-intensive, therefore for each of them parallel algorithms have been developed in SRW. For the storage ring related calculations, the parallel processing was implemented using the Message Passing Interface (MPI). For the XFEL calculations, a shared memory approach provided by the Open Multi-Processing (OpenMP) was adopted. The two parallelization methods, and their implementation in SRW, have different advantages and drawbacks: the MPI-parallelization of partially-coherent calculations for storage rings has a good scaling, but over-consumes memory, whereas the OpenMP-parallelization of time-dependent XFEL calculations is memory-efficient, but it can only scale within one multi-core server. We are reporting the results of the efficiency tests of these two types of parallel calculations, obtained for representative optical schemes. The tests were performed on an isolated server as well on a large computer cluster - the US DOE’s NERSC scientific computing facility.

The weak refraction of X-rays allows refracting optical elements to be fabricated that perturb the X-ray phase at the picometre level. This allows fine correction of the X-ray wavefront from imperfect optical elements. Adaptable refractive correcting optics are a new concept of refractive optics that produce a wavefront correction that can be varied in size and form [1] allowing an dynamic correction of X-ray wavefront following mirror or lens focusing optics. Precise measurements and simulation at Diamond Light Source of the wavefront of a spatially coherent X-ray beam focused by an elliptical mirror, demonstrate that after optimisation, focusing close to the theoretical diffraction limit is achieved. [1] David Laundy, Vishal Dhamgaye, Thomas Moxham and Kawal Sawhney, Adaptable refractive correctors for X-ray optics. Optica 6 (12), 1484-1490.2019. DOI: 10.1364/OPTICA.6.001484

The advent of 4th generation high-energy synchrotron facilities (ESRF-EBS and the planned APS-U, PETRA-IV and SPring-8 II) and free-electron lasers (Eu-XFEL and LCLS-II) allied with the recent demonstration of high- quality free-form refractive optics for beam shaping and optical correction have revived interest in compound refractive lenses (CRLs) as optics for beam transport, probe formation in X-ray micro- and nano-analysis as well as for imaging applications. Ideal CRLs have long been made available in the 'Synchrotron Radiation Workshop' (SRW), however, the current context requires more sophisticated modelling of X-ray lenses. In this work, we revisit the already implemented wave-optics model for an ideal X-ray lens in the projection approximation and propose modifications to it as to allow more degrees of freedom to both the front and back surfaces independently, which enables to reproduce misalignments and manufacturing errors commonly found in X-ray lenses. For the cases where simply tilting and transversely offsetting the parabolic sections of a CRL is not enough, we present the possibility of generating the figure errors by using Zernike and Legendre polynomials or directly adding metrology data to the lenses. We present the effects of each new degree of freedom by calculating their impact on point spread function and the beam caustics.

The optical system consisting of an X-ray parabolic axicon and traditional parabolic refractive lenses is considered. Such lenses combination makes it possible to flexibly adjust the size of the focused ring-shaped beam produced by axicon changing the number of the parabolic lenses in the optical system. The optical properties of the presented beam-shaping lens have been studied theoretically and experimentally tested. Based on the complex optical function of the lens a new approach to the phase-contrast imaging which takes advantage of the traditional X-ray microscopy and the unique optical properties of the parabolic refractive axicon was presented. Additionally, the computer simulation approach based on a Fast Fourier Transform wave optics computation was described as well as the corresponded numerical calculations of the considered optical transformations were performed. The simulation results are in good agreement with experimental ones.

We present a study of optical properties of the bilens interferometer, where there is a space (Si bulk volume) between two compound refractive lenses (CRL). This design was proposed by analogy with the well-known Billiet bilens for the visible light. It was experimentally shown that under the conditions of partial absorption of X-ray radiation by the bilens, the generated interference pattern has a double period for several central fringes instead of pattern with a constant period. It was shown by computer simulation of such peculiar interference patterns that this phenomena is due to the additional interference between the rays focused by bilens and rays transmitted through the Si material between lenses in bilens. This fact encourages us to propose a new design for bilens and multilens interferometers, in which there is no spacing between CRLs. The proposed design is the lens arrays in the interferometer are arranged in a chessboard pattern, i. e. the arrays are shifted relative to each other by the distance equal to half-length of the single lens.

X-ray Compound Refractive Lenses (CRLs) made out of diamond have a number of attractive features for applications at modern light sources, such as relatively large refractive index decrement and yet relatively low absorption for hard Xrays, low thermal expansion coefficient and high mechanical rigidity (allowing to safely use them as first optical elements of beamlines), and relatively low undesirable scattering from their volume. However, diamond CRLs are hard to fabricate and process to a (sub-)micron accuracy of the surface shape, required for aberration-free focusing of hard Xrays. We will report on results of experimental tests of first generation 2D diamond CRLs manufactured by Euclid Techlabs LLC. The tests were performed at the Coherent Hard X-ray beamline of the National Synchrotron Light Source II, and included measurements of intensity profiles of ~13 keV undulator radiation focused by one diamond lens in a low-demagnification geometry. Such geometry is typically used for the X-ray beam transport and can be used for the imaging-based diagnostics of the emitting electron beam. The quality of X-ray focusing with the new diamond CRL was analyzed by comparing the measurement results with partially-coherent wave-optics simulations performed with Synchrotron Radiation Workshop code. The tests of the diamond CRL also included measurements of small-angle X-ray scattering produced by it, and comparison of these data with the scattering data from a beryllium CRL with the same focal length.

Modern deterministic polishing processes allow fabrication of x-ray optics with almost any arbitrary aspherical surface shape. Among these optics, the so called “diaboloid” mirror is of special interest. The diaboloid mirror that converts a cylindrical wave to a spherical wave would improve focusing in x-ray beamlines implementing a diffraction element between a parabolic cylinder and a toroidal mirror. The replacement of the toroidal mirror in existing beamlines by the diaboloid mirror would mitigate aberrations. The shape of the diaboloid mirror is usually calculated numerically based on a truncated polynomial solution of the optical path problem. Here, we present an exact analytical solution for the shape of a diaboloid mirror as a function of the conjugate parameters of the mirror placed in a beamline. The derived analytical expressions for the diaboloid mirror in both the canonical and mirror-based coordinate systems are implemented in ray-tracing simulations to verify the beamline performances.

For the advanced light source including Free Electron Laser (FEL) and Synchrotron Radiation Facility, X-ray mirrors are very important component for X-ray transport in beamlines. The surface quality requirement on the mirrors for the Free Electron Laser (FEL) or for diffraction-limit application has been studied by many researchers. In this paper, the mirror quality specification in non-diffraction limited case is studied for the partial coherence light source. Simplified model for the beamline system is given and compared with other numerical simulation software. Then, the surface quality on the system performance is studied with special concern on focusing beam without structured or non-uniform pattern. Considering the characteristics of the real mirror error, the general requirement on the mirror surface quality is given for HEPS beamline design.

We describe the implementation of realistic, adaptive wavefront correction in high-brightness beamline simulations to study the correction of thermal deformation. Several planned soft x-ray and tender x-ray insertion-device beamlines in the Advanced Light Source upgrade, where wavefront preservation is paramount, rely on a common design principle.After studying the performance of a 20-channel adaptive x-ray mirror prototype, at-wavelength and with visible-light, we implemented mirror shape-control algorithms in software that are designed to restore and optimize the focused beam intensity (i.e. Strehl ratio), considering the incident wavefront’s phase and amplitude. We implemented the modeling in OASYS which is an adaptable, customizable beamline modeling platform well suited to study this issue.

The low efficiency of conventional single layer gratings at the tender X-ray region (E=1~5 keV) significantly limits the photon flux of the beamline and the development of related imaging and spectroscopy experiments in this region. To overcome this issue, multilayer coated gratings have been proposed and developed. The diffraction behavior of a multilayer grating is more complex than a single layer grating. To understand the diffraction behavior and exert the maximum potential of this new optics, we have built an analytical theory based on coupled wave theory. A high efficiency single order diffraction regime was first identified which means only one diffraction order will be excited with a certain incidence angle and structure parameters. This is applicable to blazed multilayer gratings (BMGs). To achieve maximum efficiency, the optimum grating and multilayer structures were analyzed. The highest theoretical efficiency of a BMG can reach the same value of the coated multilayer reflectance. Moreover, blazed multilayer gratings exhibit the advantage of high harmonics suppression. For the BMG, the conventional condition of maximal diffraction efficiency, Dsinα = nd, where D and d is the grating period and multilayer period, respectively, α is blaze angle, n is diffraction order, has been proved invalid. This is due to the contribution of anti-blaze facets to diffraction and effect of strongly asymmetric diffraction. Based on these, a Cr/C BMG was fabricated in collaboration with the Department for Nanometer Optics and Technology in BESSY-II. Maximum efficiency of up to 60% was demonstrated at 3 keV which is close to the theoretical prediction.

Theoretical studies of diffraction in strongly bent crystals applied to measuring spectra of X-ray Free-Electron Laser (XFEL) pulses are presented. It is shown that for bending radii below a threshold defined by the reflection the diffraction can be treated kinematically. Diffraction of XFEL pulses in bent crystals is simulated, and it is shown that the spectra can be resolved for the baseline parameters of European XFEL. The simulations help find the optimal parameters for the given experimental conditions. The possibilities of shot-to-shot spectroscopic studies and pulse duration estimation are discussed.

Single crystal based optics is widely used at X-ray Free-Electron Laser (XFEL) facilities for beam tailoring. Here, we present recent developments in simulations of coherent X-ray wavefront propagation through crystals. In particular, the Laue case of dynamical diffraction has been implemented in Synchrotron Radiation Work- shop (SRW). Various effects due to wavefront transformation of short XFEL pulses have been simulated in the WavePropaGator (WPG) framework. Possible experimental observations of the effects are discussed.

A Bragg-case X-ray dynamical diffraction propagator has already been integrated into the “Synchrotron Radiation Workshop” (SRW) physical optics simulation software package. Previous benchmarking tests on crystal monochromators assumed thicknesses many times the extinction length, for which transmission is negligible. This paper reports tests of this propagator applied to thin crystals in transmission. The chosen example is a phase retarder, which allows users to alter the polarization of an X-ray beam. Phase retarders are often applied to studies of solid-state materials with hard X-rays, which current medium-energy storage ring synchrotron sources typically produce only with linear polarization. Correct designs of phase retarders require the accurate determination of both the intensity and the phase of the diffracted wave in all polarization states. First, to approximate an incident plane wave, SRW is used to simulate the passage of a Gaussian beam of very large radius of curvature through the phase retarder. Then, the phase retarder’s effects on a typical undulator beam are simulated and the results are compared. Because X-ray phase retarders are highly sensitive to angular alignment, tolerances in misalignment are also determined. SRW simulations are compared with experimental data from the Integrated In Situ and Resonant Hard X-ray Studies (ISR) beamline at NSLSII. The design of phase retarders can therefore be optimized for X-ray beamlines that must combine variable polarization with focusing or other properties.

The emergence of new high brilliance and high coherence facilities such as X-ray Free Electron Lasers (XFELs) and 4^th generation synchrotrons open a new era in X-ray optics. Dynamical diffraction effects before disregarded are starting to play a role in the beam control of large scale facilities. In the case of XFEL facilities the temporal characteristics of the dynamical diffraction by thin perfect crystals can be used as a tool to generate femtosecond monochromatic pulses, in the case of self-seeding in the hard X-ray regime, but could even be used as method to characterize materials in this temporal range. In this contribution we present the first steps in the understanding of the spatial-displacement dependence of forward beams diffracted by thin crystals. The data collected by this technique is compared with crystal models based in dynamical diffraction theory. This type of study could open a new field to understand low strain materials in the femtosecond regime.

This presentation will focus on solving certain x-ray dynamic diffraction problems using a beam propagation method (BPM). I will show examples of using the BPM method in: 1) simulating performance of non-perfect multilayer mirrors and focusing optics, such as multilayer Laue lenses (MML), 2) predicting damage thresholds of diffraction elements such as diffraction gratings, 3) modeling scattering of x-rays form deformed crystal. A special emphasis will be placed on including imperfection and thermal deformation in simulations of performance of x-ray optical elements. Some of simulation results will be related to experimental data. I will also compare the BPM method with other approaches to theory of x-ray dynamic diffraction.

While synchrotron light facilities and Free Electron Lasers (FELs) are widely used for matter investigation, Laser Plasma Acceleration (LPA), delivering nowadays GeV electron beams in few centimeter accelerating distance, can be considered to drive undulator radiation and FEL. We report on the generation of undulator radiation on the COXINEL dedicated manipulation line designed for an FEL application. The LPA large divergence is handled with variable gradient permanent magnet quadrupoles and the high energy spread is reduced via a magnetic chicane. We evidence the undulator spatio-spectral signature on the first and second harmonics while measuring the radiation focused onto the entrance slit of a spectrometer equipped with a CDD camera. A good agreement is found between measurements and SRW simulations, using electron beam parameters in the undulator deduced from the measured initial electron beam parameters transported along the beamline. In addition, ray optics approach is compared to Fourier optics for the radiation propagation through optical elements.

Experiments conducted in large scientific research infrastructures, such as synchrotrons, free electron lasers and neutron sources become increasingly complex. Such experiments, often investigating complex physical systems, are usually performed under strict time limitations and may depend critically on experimental parameters. To prepare and analyze these complex experiments, a virtual laboratory which provides start-to-end simulation tools can help experimenters predict experimental results under real or close to real instrument conditions. As a part of the PaNOSC (Photon and Neutron Open Science Cloud) project, the VIrtual Neutron and x-raY Laboratory (VINYL) is designed to be a cloud service framework to implement start-to-end simulations for those scientific facilities. In this paper, we present an introduction of the virtual laboratory framework and discuss its applications to the design and optimization of experiment setups as well as the estimation of experimental artifacts in an X-ray experiment.

Detailed simulations of experiments carried out at modern light sources are directly related to the most efficient and productive use of these facilities for research in multiple branches of science and technology. The “Synchrotron Radiation Workshop” computer code with its Python interface, and Sirepo web-browser-based graphical user interface, currently supports physical optics simulations of coherent X-ray scattering and imaging experiments on user-defined virtual samples. We present examples of simulations of coherent scattering experiments that are typically performed at the Coherent Hard X-ray beamline at Brookhaven National Laboratory’s (BNL) National Synchrotron Light Source II. We also present several comparisons of the simulations with the results of actual coherent X-ray scattering experiments with nano-fabricated test samples produced at BNL’s Center for Functional Nanomaterials.

Simulation of beamlines at light sources is an essential part of their design and commissioning. Such simulations can be performed by the Synchrotron Radiation Workshop (SRW) code, which now has a user-friendly, browser- based interface, Sirepo. The simulations, utilizing a concept of a "virtual" beamline, can aim to optimize the specific aspects of a beamline, such as maximization of the flux, minimization of the beam size, etc. These tasks are also performed at the physical beamlines using various alignment procedures. At NSLS-II these procedures are executed by the Bluesky data collection framework. The Sirepo-Bluesky interface leverages both systems to allow for the multiparameter optimization of the X-ray source and beamline optics with the power of bluesky's plans used for the daily experiments at NSLS-II, and databroker's capabilities to retrieve the captured data and metadata to perform further analysis. Such a "collaboration" between the frameworks can be used to store the simulated results in the same database as for the experimental data, and seamlessly apply the same analysis pipelines, demonstrated in recent publications. In a simulation, multiple parameters can be changed at once and be stored as a snapshot of the "virtual" beamline in time along with the corresponding results of the simulations. A global optimization algorithm (e.g., a genetic algorithm) can then utilize the data to find the best configuration for the desired outcome. Such an optimization procedure can be seamlessly applied to the real hardware by substituting the virtual motors and detectors by the real ones.