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Over the last couple of decades, the synchrotron radiation research community has witnessed tremendous advancement in the field of X-ray imaging and microscopy. Continuing enhancement of the light ...

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source at Brookhaven National Laboratory. During spring/ summer of 2014, the storage ring was commissioned up to 50 mA without insertion devices. In the fall of 2014, we began commissioning of the project beamlines, which included seven insertion devices on six ID ports. Beamlines IXS, HXN, CSX-1, CSX-2, CHX, SRX, and XPD-1 consist of elliptically polarized undulator (EPU), damping wigglers (DW) and in-vacuum undulators (IVU) covering from VUV to hard x-ray range. In this paper, experience with commissioning and operation is discussed. We focus on reaching storage ring performance with IDs, including injection, design emittance, compensation of orbit distortions caused by ID residual field, source point stability, beam alignment and tools for control, monitoring and protection of the ring chambers from ID radiation.

The first eight insertion devices (IDs) at the NSLS-II were commissioned during the fall run of 2014. In this paper we discuss commissioning of the synchrotron radiation protection (SRP) system and beamline frontends (FE) for the respective IDs. We describe the diagnostics utilized if FE commissioning and a procedure that was used for the alignment of the photon beam from insertion devices in the beamline frontends. Then we discuss the current status of the SRP system and operation of the commissioned frontends.

We describe a high-throughput scanning X-ray fluorescence (XRF) microscopy setup using a microfocused synchrotron X-ray beam, which is optimized for in-parallel X-ray characterization of composition and crystalline structure of combinatorial samples. We present X-ray fluorescence elemental maps of a full ternary Co x Mn y Ge 1− x − y composition-spread thin film and discuss the quantitative analysis method used for obtaining the ternary composition.

We discuss important experimental considerations and high-throughput synchrotron-based techniques for structural characterization of binary and ternary composition-spread thin films. We apply these techniques to obtain detailed structural phase diagrams of CoMnGe ternary alloy system.

Current knowledge of fine-particle airborne pollution concentrations and constituents with diameters below 2.5 μm (PM2.5) is limited. Sources are both natural and man-made. Here we describe two types of experiments performed using the advanced photon source facility at Chicago, and compare the results with PIXE analysis on the same fine particle filters. These are firstly broad beam (2 mm) studies with tuned synchrotron beam energies to help resolve over-lapping X-rays, and secondly highly focused X-ray beam studies (0.2 μm) of individual fine particles from airborne pollution combustion sources.

Understanding the fate of heavy-metal contaminants in the environment is of fundamental importance in the development and evaluation of effective remediation and sequestration strategies. Among the factors influencing the transport of these contaminants are their chemical speciation and the chemical and physical attributes of the surrounding medium. Bacteria and the extracellular material associated with them are thought to play a key role in determining a contaminant’s speciation and thus its mobility in the environment. In addition, the microenvironment at and adjacent to actively metabolizing cell surfaces can be significantly different from the bulk environment. Thus, the spatial distribution and chemical speciation of contaminants and elements that are key to biological processes must be characterized at micron and submicron resolution in order to understand the microscopic physical, geological, chemical, and biological interfaces that determine a contaminant’s macroscopic fate. Hard X-ray microimaging is a powerful technique for the element-specific investigation of complex environmental samples at the needed micron and submicron resolution. An important advantage of this technique results from the large penetration depth of hard X-rays in water. This advantage minimizes the requirements for sample preparation and allows the detailed study of hydrated samples. This paper presents results of studies of the spatial distribution of naturally occurring metals and a heavy-metal contaminant (Cr) in and near hydrated bacteria (Pseudomonas fluorescens) in the early stages of biofilm development, performed at the Advanced Photon Source Sector 2 X-ray microscopy beamline.

We have used synchrotron radiation x-ray microdiffraction to study the microstructure and strain variation of copper interconnects. Different types of local microstructures have been found in different samples. Our data show that the Ti adhesion layer has a dramatic effect on Cu microstructure. On site electromigration test has been conducted and strain profile along the same interconnect line was measured before and after this electrical stressing. Cu fluorescence scan was used to find the mass variations along the line. Voids and hillocks can be clearly identified in this scan. x-ray micro-diffraction was used to measure the strain change around the interesting regions.

Optimization of blade type X-ray Beam Position Monitors (XBPM) was performed for NSLS-II undulator IVU20. Blade material, configuration and operation principle was analyzed to improve XBPM performance. Optimization is based on calculation of the XBPM signal spatial distribution. Along with standard photoemission blades, Diamond Detector Blade (DDB) was analyzed as XBPM signal source. Analyses revealed, that Diamond Detector Blade XBPM would allow overcoming drawbacks of the photoemission type XBPMs.

The intermediate-energy scanning x-ray microscope at beamline 2-ID-B at the Advanced Photon Source is a dedicated instrument for materials and biological research. The microscope uses a zone plate lens to focus coherent I-4 keV x-rays to a 60 nm focal spot of 10 9 photons/ s onto the sample. It records simultaneous transmission and energy-resolved fluorescence images. We have used the microscope for nanotomography of chips and microspectroscopy of cells.