Nuclear-resonance beamline at ESRF

Summary The Nuclear-Resonance Beamline at ESRF is dedicated to the excitation of nuclear levels by synchrotron radiation. The source of radiation and optical elements are optimized to provide an intense, highly monochromatic, collimated and stable X-ray beam of small cross-section at the M?ssbauer transition energies between 6 keV and 30 keV. The set-up of the beamline allows to perform studies in diffraction, small-angle scattering, forward scattering and incoherent scattering. Equipment is available to maintain the sample at variable temperature and magnetic field. Fast detectors and timing electronics serve to separate the delayed nuclear scattering from the ?prompt? electronic scattering and to measure the time spectra of nuclear radiation with sub-nanosecond resolution. The general layout and the parameters of the beamline are reported. Typical domains of applications are discussed and illustrated by first experimental results. Paper presented at ICAME-95, Rimini, 10–16 September 1995.     

X-ray Optics at the ESRF

For nearly 20 years, the X-ray Optics Group of the ESRF has been playing a major role in the development of new X-ray optical systems, many of which are widely used at synchrotrons around the globe.     

High-pressure facilities at the ESRF

Abstract

Several beamlines at the European Synchrotron Radiation Facility in Grenoble are being designed with high-pressure experiments in mind. Among the first seven beamlines the Microfocus Beamline, the Materials Science Beamline, the Laue White Beamline and the High Energy Beamline are of particular interest for high-pressure diffraction experiments. These experimental stations are outlined and their characteristics are compared.

Presented at the IUCr Workshop on ‘Synchrotron Radiation Instrumentation for High Pressure Crystallography’, Daresbury Laboratory 20-21 July 1991     

Environmental Sciences at the ESRF

In the past two decades, environmental sciences have increased their share in the research portfolios of European synchrotrons, not least for their topicality from a societal point of view. As this field overlaps with many other disciplines, the ESRF decided to establish, in 2005, a dedicated Review Panel for Environmental Science and Cultural Heritage.     

Engineering Materials Research at ESRF

The use of synchrotron radiation in fundamental and applied materials research is expanding in Europe. Traditionally, synchrotron radiation was used to study the final properties of metal alloys. More recently, due to improvements of the sources, detectors, and experimental techniques themselves, materials processing can be studied in situ on an industrial scale. Various techniques, such as imaging, tomography, and diffraction, are used to study material processing, solidification, thermo-mechanical treatment, shaping, and mechanical behavior under various conditions such as stress and temperature. The use of these techniques in real time during the processing is essential to understand, and furthermore to optimize, the process yielding desired materials properties.     

Beamline 12.2.2: An Extreme Conditions Beamline at the Advanced Light Source

The Advanced Light Source (ALS) is a 1.9-GeV, third-generation synchrotron optimized for the production of VUV and soft X-rays from undulators. There is also a hard X-ray program at the ALS, which is based around three 6-T superconducting bending magnets [1 Robin, D. Proceedings of the 2002 European Particle Accelerator Conference. Paris, France. pp.215Geneva: EPAC..  [Google Scholar]] that shift the critical energy from 3 keV to 12 keV. The extreme conditions beamline at the ALS is situated on Beamline 12.2.2, which benefits from radiation produced by one of these superbend sources. The beamline is designed for X-ray diffraction, X-ray spectroscopy, and X-ray imaging of samples held in diamond-anvil high-pressure cells (DACs). In a DAC, samples are on the order of 10 to 50 μm in diameter and 10 to 30 μm thick and are contained in a metal gasket of typical inner diameters of 100 to 150 μm. For high-quality diffraction patterns with little or no contamination from diffraction from the gasket, the X-ray beam size needs to be on the order of 10 μm × 10 μm.     

Chemical Applications of Nuclear Magnetic Resonance at High Fields

Abstract

A review confined to nuclear magnetic resonance measurements in a particular field-strength range needs some justification. Although the advent of the superconducting magnet in NMR presents quite novel problems for the spectrometer designer, and involves the user in some new operating techniques, the jump from 100 MHz (for proton resonances) to 220 MHz does not involve any new form of spectroscopy, any more than did the earlier advances from 40 MHz to 60 MHz, and thence to 100 MHz. The advantages in spectrometer performance which result from using a superconducting magnet are of degree, not of kind, and one is not called upon to learn anything new about NMR in order to interpret the spectra; indeed, the effect in many cases is to simplify the interpretation, so that a sophisticated quantum-mechanical approach is less often needed.     

Quantum Discord in Nuclear Magnetic Resonance Systems at Room Temperature

We review the theoretical and the experimental researches aimed at quantifying or identifying quantum correlations in liquid-state nuclear magnetic resonance (NMR) systems at room temperature. We first overview, at the formal level, a method to determine the quantum discord and its classical counterpart in systems described by a deviation matrix. Next, we describe an experimental implementation of that method. Previous theoretical analysis of quantum discord decoherence had predicted the time dependence of the discord to change suddenly under the influence of phase noise. The experiment attests to the robustness of the effect, sufficient to confirm the theoretical prediction even under the additional influence of a thermal environment. Finally, we discuss an observable witness for the quantumness of correlations in two-qubit systems and its first NMR implementation. Should the nature, not the amount, of the correlation be under scrutiny, the witness offers the most attractive alternative.     

Phase-Contrast Mammography at the SYRMEP Beamline of Elettra

At the SYnchrotron Radiation for MEdical Physics (SYRMEP) beamline of Elettra, a widespread research activity in bio-medical imaging has been developed since 1997 [1 Arfelli, F. 1998. Low-dose phase contrast X-ray medical imaging. Phys. Med. Biol, 43: 2845 [Google Scholar]]. The core program carried out by the SYRMEP research team concerns the use of synchrotron radiation (SR) for mammography in the effort of improving image diagnostic quality innovating the imaging technique and the detection system.     

Nuclear Magnetic Resonance Imaging

Abstract

The advent of X-ray computed tomographic (CT) imaging revolutionized the evaluation of a wide range of pathological conditions by producing thin tomographic sections through the body with remarkable anatomical detail. By the early 1980s, X-ray CT was an established imaging modality, and a second computer-based form of imaging was emerging from the research laboratory into the clinic. The second wave of the imaging revolution has been the development of NMR imaging (usually referred to as magnetic resonance imaging, or MRI) and its acceptance as the preferred modality for much neurological and musculoskeletal imaging. MRI's soft-tissue contrast and resolution is superior to that of other imaging techniques, the low NMR signal from bone renders it superior to X-ray CT in many cases for images of the head and spine, it has more varied contrast possibilities than CT, and can image in any plane without repositioning the patient. In spite of the high cost of purchase and installation, MR scanners are proliferating rapidly, and techniques and clinical applications for MR imaging continue to advance at an equally rapid rate.     

Engineering Science at the I12 Beamline at Diamond Light Source

Synchrotron-based engineering science covers a large field of applications. However, they are all connected in two ways. First, the very synchrotron techniques employed to study the various applications all work in the same way in that they determine structural parameters on the atomic and microscopic scale. Secondly, the portfolio of applications discussed here describes the complete life cycle of an engineering material, starting with processing of the base material—often from the melt—then the characterization of material properties, followed by the forming and joining into components, then component characterization during service, material aging, damage and failure and, finally, recycling or decommissioning. The structural problems which occur during the different stages in the life cycle of a material are complex, due to the advanced material technology of today's devices. We have created alloys for special applications, compound materials with novel properties, sophisticated bulk and surface treatments, and new forming and joining techniques. We are also concerned with the effect of the material on the environment after it has ended its service.     

Scanning Probe Instruments and Synchrotron Light at the ESRF

In 2004, the aim of the X-Tip European Project was to pursue the integration of scanning probe microscopy techniques into synchrotron radiation beamlines to provide new opportunities to both fields of microscopy and spectroscopy. Given the limited X-ray focusing capabilities at that time and the difficulty of alignment, the first emphasis was given to the possibility of exploring the morphology of the sample surface within the area illuminated by the X-rays, selecting an area of interest and, using the scanning tip, aligning it into the X-ray beam and extract by total electron yield spectroscopic information, with lateral resolutions ideally defined by tip dimensions.     

Mechanically Detected Nuclear Magnetic Resonance at Room Temperature and Normal Pressure

Mechanically detected magnetic resonance (MMR) is a new technique for detecting electron or nuclear spin signals. All preceding experiments have been carried out in a <10⁻³Torr vacuum at room temperature or at low temperatures down to 6 K. In this article the first MMR experiments at normal pressure and room temperature are presented. The mechanically detected NMR signals resulted from ammonium nitrate and ammonium sulfate. In addition, techniques for determiningT₁andT_1ρwith mechanical experiments were developed. IfT_1ρis not more than two or three times smaller thanT₁, an inversion-recovery technique, first used for the detection of¹⁹F spins at low temperatures, can be used. It could be shown that this technique also works in principle at room temperature.     

Nuclear Magnetic Resonance in Industry

It is the author's intention to demonstrate progress in the application of nuclear magnetic resonance (NMR) in industry over a period of nearly 30 years.