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We have designed a non-imaging telescope for measurement of the spectral irradiance of the moon. The telescope was designed to be integrated into a wing pod of a National Aeronautics and Space Administration ER-2 research aircraft to measure lunar spectral irradiance during flight. The telescope and support system were successfully flown in August 2018 at altitudes near 21 km and at speeds of ∼760 km/h. The wing pod in which the telescope is mounted has an opening through which the moon can be observed. The mount exposes the telescope to high winds, low pressures, temperatures near −60 °C, and vibrations both due to flight and due to the motion of the aircraft on the ground. This required a telescope design with high thermal stability and high resistance to shock. The optical design of the telescope is optimized to have high throughput and spatially uniform transmission from 380 nm to 1000 nm over a field of view about three times the angular size of the moon as viewed from the Earth. The final design resulted in a telescope with singlet design incorporating a 139.7 mm lens with an effective focal length of 377 mm and a field of view of 1.6°. The light from the telescope is introduced into an integrating sphere, which destroys the image and the polarization for measurement by a fiber-coupled spectroradiometer. Herein, we present an overview of the instrument and support system with emphasis on the telescope design. [ABSTRACT FROM AUTHOR]

Before being used in an extreme-ultraviolet (EUV) scanner, photoresists must first be evaluated for sensitivity and tested to ensure that they will not contaminate the scanner optics. The new NIST facility described here provides data on the contamination potential of the outgas products of a candidate resist by simultaneously irradiating a multilayer optic and a nearby resist-coated wafer with EUV radiation. The facility can also be used without changing its configuration to provide accurate resist dose-to-clear measurements. Detailed, real-time information on the rate of contamination growth is given by a unique, in situ imaging ellipsometer. We will describe the optical layout, mechanical design, and capabilities of the beamline, finally presenting experimental examples of its capabilities. [ABSTRACT FROM AUTHOR]

The application of speckle metrology to high strain rate materials characterisation, through the use of appropriate high-speed photography, provides an exciting opportunity for measurements to be performed on materials, and in loading configurations, which were not previously possible. In particular, a full understanding of the mechanical properties of inhomogeneous materials such as composites, geological and biological materials at high strain rates, requires more data than has previously been provided by the split Hopkinson pressure bar, which only gives a measure of average specimen response. Following from a separate paper by Siviour and Grantham describing the application of speckle metrology to the Hopkinson bar, this paper discusses recent experiments in which this application was used to make previously unobtainable measurements of specimen response. Results are presented from experiments performed on a polymer bonded explosive simulant and long polymer rods. These experiments were designed to evaluate the technique in a number of different configurations, as well as providing useful experimental data on these materials. In addition, we revisit the use of speckle metrology in the high strain rate Brazilian test. [ABSTRACT FROM AUTHOR]

Digital speckle radiography is a measurement technique which is capable of visualizing internal flow fields within an opaque material undergoing a ballistic impact. This recent development has been successfully applied to the study of polyester, cement, sand and glass targets. The technique is based on digital speckle photography but, instead of producing the required speckle pattern by traditional means, the specimen is seeded with a layer of X-ray opaque filings. By utilizing two X-ray heads and varying the delays and position of the seeded layer, a full three-dimensional displacement map can be built up. The theories behind the technique are introduced, and results presented from two-dimensional displacement measurements on sand subjected to rod impact and three-dimensional measurements of cement being impacted by a shaped charged jet. [ABSTRACT FROM AUTHOR]

The lifetime of multilayer mirrors is an outstanding problem on the road to commercialization of extreme-ultraviolet (EUV) lithography. The mirrors are exposed to high-intensity EUV radiation in a vacuum with traces of water vapor and hydrocarbons. The combination of EUV and reactive species leads to chemical degradation of the mirror surfaces—carbon deposition and/or oxidation of the Si surface. In order to understand and quantify these processes, as well as to study mitigation schemes, we have constructed a dedicated synchrotron-based facility with the capability to deliver high-intensity EUV radiation in a variety of trace-gas atmospheres. The facility features a spherical Mo–Si coated mirror and a thin Be foil captured in a gate valve, which serves as both a spectral filter and vacuum seal. We will describe this facility and its performance. [ABSTRACT FROM AUTHOR]

Radiometric experiments often require comparatively high intensities in the extreme ultraviolet, in the microwatt range. The monochromators that provide the high throughput needed for these experiments, though, do not always allow for end stations to be switched out easily. At the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility, the only beamline with sufficient extreme-ultraviolet power has a multi-ton endstation, which cannot be moved. We will describe a set of transfer optics that allow the photon beam to be collimated and deflected through a port on the downstream end of the large chamber. This allowed an absolute cryogenic radiometer to be attached, with the entrance cavity underfilled. We will describe ray-tracing results and offer preliminary results of the radiometer-based throughput of the system. [ABSTRACT FROM AUTHOR]

We compared the healthcare costs associated with an integrated care model to an enhanced referral model for the treatment of depression, anxiety, and at-risk drinking from the randomized Primary Care Research in Substance Abuse and Mental Health for the Elderly study. We examined total healthcare costs and cost components, separately for Veterans Affairs (VA) and non-VA participants. No differences in total health expenditures were detected between study arms. No differences in behavioral health expenditures were detected for non-VA sites, but the VA integrated arm had slightly higher ($38; p < 0.05) behavioral health costs. Differences in other types of services use were detected. [ABSTRACT FROM AUTHOR]

Reports on the operational principles and fundamental parameters at the Synchrotron Ultraviolet Radiation Facility in the U.S. Use of synchrotron radiation for metrology; Improvement of the radio-frequency system; Construction of a compact synchrotron radiation light sources.

Abstract: The calculability of synchrotron radiation (SR) makes electron storage rings wonderful light sources for radiometry. The broadband nature of SR allows coverage of the entire spectral region from the X-ray to the far-infrared. Compact low-energy storage rings like the Synchrotron Ultraviolet Radiation Facility SURF III are perfect sources for radiometric applications, because the output spectrum can be custom-tailored to the user''s needs: low current operations can simulate the solar spectrum, changes to the electron energy can address higher-order contributions of spectrometers and monochromators, and manipulation of the source size can increase the lifetime or change the radiation density. At large multi-user facilities these special operational conditions are generally not possible, since many users have to be satisfied simultaneously. At SURF III, NIST maintains one of the best SR-based infrared to soft X-ray calibration programs in the world: standard lamp calibrations, detector calibrations, and measurements of optical properties are routinely performed at SURF with great reliability and accuracy. [Copyright &y& Elsevier]