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The excellent performance of highly oriented pyrolytic graphite (HOPG) as monochromator, analyzer and filter material for neutron instrumentation was discovered more than 50 years ago. Even though HOPG has been in use for a long time, there is still room for improvements regarding its optimized use in neutron beam conditioning. The features of a novel concept called POSI based on careful x-ray characterization of the HOPG crystals and on proven mounting and focusing technologies show that the efficiency of HOPG monochromators can be increased while decreasing complexity and cost. Moreover, by combining HOPG and bent perfect silicon crystals the functionality of separate single monochromators and analyzers can be expanded to a wider range of applications provided by dual systems or bichromators. [ABSTRACT FROM AUTHOR]

Endurance encompasses more than 30 new or upgraded instrument and infrastructure projects, rolled out over 8 years between 2016 and 2023. Many new or upgraded instruments have already been deployed and are in user-operation including: the fission-fragment gamma ray spectrometer, FIPPS; the upgraded cold-neutron TOF spectrometer IN5; new thermal TOF spectrometer PANTHER; and a second protein crystallography station, DALI. The D3 hot-neutron diffractometer and IN20 thermal triple-axis spectrometer have been upgraded while new and additional detectors for the SANS instruments D11 and D22 have been installed. The D16 cold-neutron diffractometer has been fully modernised and new coldneutron imaging instrument, NeXT, has been installed. Delivering a full suite of modernised instrumentation is dependent on the renewed in-pile beam extraction, H1-H2, new H24 (thermal) and H15 (cold) neutron guides and the in-house development and manufacture of critical technologies such as neutron detectors, monochromator optics and polarisation components. The new H24 guide provides dedicated endof-guide positions to the upgraded D10+ single crystal diffractometer, IN13 backscattering instrument and the new XtremeD powder and single-crystal diffractometer. H15 will accommodate a substantially upgraded D(00)7 polarised diffuse scattering and spectroscopy instrument while D11 will be rebuilt and relocated with an optically cleaner collimation. Two additional end-of-guide positions are available for new instrumentation: The SHARP+ cold-neutron TOF spectrometer and a 4th SANS instrument, SAM. The success of Endurance will provide users with a fully modernised suite of world-class instruments. [ABSTRACT FROM AUTHOR]

Feasibility of focusing high-resolution three-axis diffractometer with the polycrystalline sample between the monochromator and the analyzer was tested for studies of finer effects of powder diffraction lines and for investigations of special tasks of powder diffractometry. The focusing 3-axis diffractometer set-up equipped with bent perfect crystal monochromator and analyzer offers the sensitivity in determination e.g. of strains in polycrystalline materials ε =Δd/d close to 10-5. Together with special tasks of strain/stress studies related namely, to plastic deformation, it permits to study a finer substructure of individual diffraction lines which can appear e.g. in case of polycrystalline alloys where more phases having very close values of the lattice spacing could exist. Resolution properties of the high-resolution diffractometer setting will be documented on several experimental results obtained on unconventional bulk samples. [ABSTRACT FROM AUTHOR]

TPS 31A fast tomography and energy-resolved elemental mapping projection X-ray microscopy (PXM) and transmission X-ray microscopy (TXM) beamline of NSRRC is under construction and commissioning. This beamline will provide four operating modes including (1) PXM with white light mode, (2) PXM with double multilayer monochromator (DMM) mode, (3) PXM with double crystal monochromator (DCM) mode, and (4) TXM with double crystal monochromator (DCM) mode. All modes are capable of absorption contrast and phase contrast of images. The spatial resolution of three PXM modes is 0.5 µm. The field of view of PXM-white light, PXM-DMM, and PXM-DCM mode is 25×18 cm2, 25×10 mm2 and 25×3 mm2, respectively. The temporal resolution of PXM modes can approach 1ms/frame and 45 sec/tomography. The in operando tomography and energy-resolved elemental mapping within 2D image as well as tomography are feasible. The spatial resolution and field of view of TXM mode is expected as 30 nm and 30 µm, respectively. The energy-resolved elemental mapping within 2D image and tomography is practical. [ABSTRACT FROM AUTHOR]

The paper shows the possibility of using luminophores to identify liquid flows in the rock. The spectral characteristics of the excitation (absorption) and luminescence of produced water with a phosphor can provide information on the hydrodynamic relationship between injection and production wells and on the efficiency of field development. A method for measuring the spectral characteristics of excitation and luminescence of water based on a spectrofluorimeter has been developed. The technique includes primary visual control and sampling, simultaneous scanning with two monochromators, measurement and analysis of the excitation (absorption) spectrum, mathematical operations with graphs to determine the luminescence parameters (Stokes shift, relative flux, etc.). 2D scanning is also possible to obtain 3D excitation and luminescence patterns. The technique gives recommendations on the choice of spectral ranges, receiver sensitivity, number of averaging points, scanning step, etc. [ABSTRACT FROM AUTHOR]

Although mini-spectrometers based on integrated optical elements (fiber-coupled), an image sensor and a circuit are penetrating in a variety of applications, including color measurement, agriculture and food safety, process control, etc., diffraction grating based monochromators are still preserve their role as a reference device for spectral measurements. Precise characterization and calibration of spectral sensing devices, illumination sources and various optical filters and windows require a precisely calibrated monochromator. Pen-type spectral lamps filled with noble gases and their mixture are widely used for this purpose. However, these lamps are very fragile and have short life time when employed with an unproper power supply. In this work we present experimental results of application of multi-color tunable laser source for fast and precise calibration of Czerny-Turner monochromator. The obtained results are compared with those obtained by means of several different pen-type lamps. The experimental results of this comparison are discussed in this work. [ABSTRACT FROM AUTHOR]

We developed an experimental setup for the measurement of soft X-ray excited optical luminescence at the reflectivity beamline (BL-4), Indus-1 synchrotron radiation source. The soft X-ray excited visible luminescence signal from sample was collected using a lens assembly and focused on to a ∼200 µm optical fiber coupled to thermoelectric (TE) cooled spectrometer. The photo luminescence signal from the samples mounted inside a vacuum chamber was brought to the luminescence collection unit mounted in the air through a glass view port. The toroidal grating monochromator of the beamline provided the soft x-rays for excitations in the range of ∼10 eV to 300 eV (100 nm – 4 nm) and the resultant optical luminescence was recorded in the range of ∼350 nm to 900 nm. The developed setup was demonstrated by the recording the visible emission from standard scintillator materials (Cr:Al2O3, Ce:YAG, etc.) and β-Ga2O3 nanostructure. [ABSTRACT FROM AUTHOR]

In this paper, a new effective wavelength calibration technique has been investigated and calculated for the calibration of different monochromator systems. Different calibration lamps have been tested effectively with respect to similar studies. Extended wavelength accuracy calibration has been made for the spectrophotometer systems, which have different grating with different spectral range. For each grating, different calibration lamps was used. Wavelength calibration over extended range has been possible by using orders of gratings. Integrating sphere usage has been a simpler way compared to conventional optical setups and a unique approach on uniformly transferring radiation of the calibration lamps to monochromator systems. This experimental setup, allows the correct wavelength of the radiation to reach entrance slit without causing optical aberrations. Many parameters have been analyzed in uncertainty measurements both standard uncertainty calculation method, which are based on the “Guide to the Expression of Uncertainty in Measurement” (GUM) and other method is the Monte Carlo (MC) described in e GUM Supplement-1. Hence, the precision is improved in results. Extended uncertainty results are in between 0.02 nm and 0.3 nm with 95% confidence level (k=2) for both monochromator systems. [ABSTRACT FROM AUTHOR]

The EXAFS BL-09 beamline of Indus-2, RRCAT have been in growing demand owing to their outstanding performance for x-ray absorption (XAFS) data collection in transmission mode and fluorescence mode. To take full advantage of the state-of-the-art of this beamline, a significant effort has been devoted for designing of 5-Circle diffractometer to perform depth-selective XAFS study and fast, intuitive beamline controls through EPICS and SPEC diffractometer-control program to perform x-ray reflectivity (XRR) and XAFS measurements. In the present work, we mainly focus on the communication of Si(111) double crystal monochromator and 3 ionization chambers whose output is connected with 4 channel TetrAMM picoammeter through EPICS for XAFS measurement and using Mythen Detector (1D) for X-ray reflectivity (XRR) measurement at various energies. [ABSTRACT FROM AUTHOR]

The TPS 13A biological small-angle X-ray scattering (BioSAXS) beamline under construction is equipped with 4-m IU24 undulator for X-rays in the energy range of E = 4-23 keV (covering the K-edge absorptions from Ca to Ru). The beamline aims for cutting-edge researches in biomacromolecular structures and kinetics, in solid and solution, covering a wide length scale from atomic to micrometer scale and time resolution down to μs. To achieve the goals, the beamline integrates double-multilayer and double-crystal monochromators (DMM/DCM) to have an option of high flux of 4 × 1014 photons/s or a high energy resolution of ΔE/E = 1.5×10−4. The DCM together with a horizontal four-bounce crystal collimator (4BCC) will be implanted for low beam divergence to perform 2D ultra-SAXS (USAXS). To keep a common X-ray beam path of the operation modes, DMM and DCM are integrated into one rotating cradle in a same chamber for a common beam exit. Microbeam with reasonable beam divergence for SAXS/WAXS structural mapping will be realized with a virtual source defined by a set of high precision/stability slits and another set of K-B mirrors for a focus at the sample position with a demagnification close to 1.3:1. Two beam position monitors, with intensity and position feedbacks respectively to the virtual source slits and the 4BCC and a vertical deflection mirror, are used mainly to stabilize microbeam intensity and position within 1 μm in the vertical and horizontal directions. This TPS 13A BioSAXS beamline will be commissioning at the end of 2019. [ABSTRACT FROM AUTHOR]

A plane-grating monochromator for the extreme-ultraviolet region that uses a plane grating operated at variable included angle and illuminated in converging light has been realized. The configuration consists of three optical elements: the focusing mirror, the plane grating and the plane mirror. In the proposed design, the spectral focusing is kept on the exit slit plane by changing the grating included angle through the use of an additional plane mirror after the grating. The coma aberration given by the grating is compensated by an opposite coma introduced by the focusing mirror, that is used in a very asymmetrical configuration. The feasibility of the configuration has been demonstrated on a monochromator for the 10-80 eV region, with sub-10-meV output bandwidth. The correction of defocusing and coma at the proper included angle has been clearly demonstrated. The monochromator efficiency has been measured to be in the 0.08-0.18 range. A plane-grating monochromator for the extreme-ultraviolet region that uses a plane grating operated at variable included angle and illuminated in converging light has been realized. The configuration consists of three optical elements: the focusing mirror, the plane grating and the plane mirror. In the proposed design, the spectral focusing is kept on the exit slit plane by changing the grating included angle through the use of an additional plane mirror after the grating. The coma aberration given by the grating is compensated by an opposite coma introduced by the focusing mirror, that is used in a very asymmetrical configuration. The feasibility of the configuration has been demonstrated on a monochromator for the 10-80 eV region, with sub-10-meV output bandwidth. The correction of defocusing and coma at the proper included angle has been clearly demonstrated. The monochromator efficiency has been measured to be in the 0.08-0.18 range. [ABSTRACT FROM AUTHOR]

One of the beamlines at Taiwan Photon Source (TPS), numbered as TPS 44A, is for Extended X-ray Absorption Fine Structure experiments. The main components include a collimation mirror, a focusing mirror, and a quick-scan double crystal monochromator. There are also various diagnosis and monitoring equipment. It uses four-blade slits to constrain the beam size and block unwanted part. Besides, current amplifiers are attached to the slits. At the locations in front or at rear of some mirrors which can change the direction of the x-ray beam, there are fluorescent screens and cameras to observe positions and strength of the beam. Most of them need electronic motors or high-pressure air to be movable and controllable from a remote control system. If there exists one integrated control system for all equipment, it will be easier for the scientists to operate the beamline, adjust the conditions of various parameters, do the commissioning, and concentrate on the experiments. [ABSTRACT FROM AUTHOR]

We have constructed a new soft X-ray beamline, namely the Taiwan Photon Source (TPS) 45A NSRRC-MPI beamline, to facilitate submicron angle-resolved photoemission spectroscopy (ARPES) experiments with ultra-high energy resolution. The beamline uses an elliptically polarized undulator with 46 mm magnet period (EPU46) that provides photon energies from 280 to 1500 eV with horizontal and vertical linear polarization, as well as left and right circular polarization. The vertical focusing mirror (VFM) and the active grating monochromator (AGM) utilize the novel 25-actuator optical surface bender developed for ultra-high resolution soft X-ray spectroscopies. With the surface slope error being reduced down to 0.03 μrad root-mean-square (rms) by the bender as verified by the long trace profiler (LTP) measurements, the ray-tracing simulation shows that an energy resolution of 5 meV can be achieved at 750 eV photon energy and the beam spot size can each 0.5 μm × 0.4 μm at the sample position. By adjusting only the 6 actuators to control the surface major profile, our preliminary results show that the VFM is able to focus 70% of the photon flux from EPU46 through an entrance slit set at 1.9 μm opening. As deduced from the measured ARPES data at the Fermi-level of Au, the energy resolving power of the monochromator was found to reach 34,000 full-width-half-maximum (FWHM) at 850 eV photon energy. By using the in-vacuum LTP measurement system currently under development and all 25 actuators of the surface bender, we anticipate to further reduce greatly the intrinsic and thermal-induced slope errors of the VFM and AGM. It is feasible that the overall ARPES energy resolving power can reach the 140,000 target in the soft X-ray spectral region. [ABSTRACT FROM AUTHOR]

The X-ray beamline TPS 02A is making use of the bending magnet source at the Taiwan Photon Source (TPS), which is dedicated to performing full-field hard X-ray projection imaging at micron size spatial resolutions in the photon energy range of 5 - 25 keV. It provides the photon flux > 4.2 × 1011 photons·s−1 with energy resolution < 1.72 × 10-3, the beam size is 35.5 (H) × 8.5 (V) mm² and beam divergence is 1.2 (H) × 0.3 (V) mrad² at the sample position. The microscope is capable of examining anatomical information and internal distribution of microstructures by tuning the energy of the photon source to the absorption edge of the samples through the use of a monochromator. Phase contrast tomography is also available for imaging the fine details of in the morphology of the sample. [ABSTRACT FROM AUTHOR]

In order to ensure rapid and successful operation of the high performance beamline instruments and optics, a test beamline (09B) has been built at Shanghai Synchrotron Radiation Facility (SSRF) for the at-wavelength measurements. The bending magnet is employed as the light source, and the acceptance angle is2.5×0.3mrad². The beamline optical elements: 1D compound refractive lens, water cooling double crystal monochromator, toroidal mirror and other optical components could be switched in the vacuum for different operational modes. A KB mirror system is employed to micron focus at the experimental station, and the beamline provides 100mm spot size in horizontal direction. The beamline photon energy range is 4-50keV, energy resolution is 5x10−4@10keV and photon flux is 3x1011phs/s@300mA. Variety instruments and detectors have been provided for the diffraction, spectroscopy, imaging and other at-wavelength measurement. Details of the beamline optical design and energy resolution measuring performance of the high energy double Laue crystal monochromator and water cooling double crystal monochromator are also presented in this paper. [ABSTRACT FROM AUTHOR]

A soft X-ray nanoscopy beamline (SXNB) at the Taiwan Photon Source (TPS) is designed to deliver photons of 90 – 2,500 eV from an elliptically polarized undulator to two state-of-the-art microscopy stations hosting the scanning transmission X-ray microscope (STXM) and the photoelectron related imaging and nanoscope (PRINS), respectively. The heart of SXNB is an active grating monochromator (AGM) that optimizes the flux and energy resolution at the same time while maintaining a stable focal spot on the sample. This article describes the design concept, optical layout, and simulation results of SXNB. [ABSTRACT FROM AUTHOR]

A biosafety level-2 beamline for macromolecular crystallography is constructing at SSRF, which is one of the beamlines in phase-II beamline project approved at 2016 by the central government of China. This beamline will provide the capability of conducting the experiment on determination of the virus-related protein structure from crystals. To fulfill this aim, the end station is emphasized on the biosafety design which must meet the Chinese laws and regulations. For the limited source of insertion section in the storage ring, the beamline will be one of the canted beamline, sharing the insertion with the ultra-small angle X-ray scattering beamline. The photon source will be a 1.6 m long, in-vacuum undulator with period of 22 mm. The optics will consist of a deflection flat mirror to increase the distance of two canted beamline, a cryogenically cooled Si(111) double-crystal monochromator and focusing mirrors. The focus scheme is realized with two-stage focus scheme in horizontal and one stage focus in vertical direction. At the sample position the focused beam is 20 micron in horizontal and 10 micron in vertical. The beam size could be changed by inserting the compound refractive lens. The beamline will deliver a high flux beam in the 7-18 keV energy range, with the energy resolution of ΔE/E ~2×10−4. In addition to the main beamline, the endstation will be negative pressure control and be functional divided to meet the biosafety regulations. This report shows the current status of the beamline design. [ABSTRACT FROM AUTHOR]