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The 1.6 m clear aperture solar telescope in Big Bear is operational and with its adaptive optics (AO) system it provides diffraction limited solar imaging and polarimetry in the near-infrared (NIR). While the AO system is being upgraded to provide diffraction limited imaging at bluer wavelengths, the instrumentation and observations are concentrated in the NIR. The New Solar Telescope (NST) operates in campaigns, making it the ideal ground-based telescope to provide complementary/supplementary data to SDO and Hinode. The NST makes photometric observations in Hα (656.3 nm) and TiO (705.6 nm) among other lines. As well, the NST collects vector magnetograms in the 1565 nm lines and is beginning such observations in 1083.0 nm. Here we discuss the relevant NST instruments, including AO, and present some results that are germane to NASA solar missions. [ABSTRACT FROM AUTHOR]

Future NASA X-ray spectroscopy missions will require high throughput, high resolving power grating spectrometers. Off-plane reflection gratings are capable of meeting the performance requirements needed to realize the scientific goals of these missions. We have identified a novel grating fabrication method that utilizes common lithographic and microfabrication techniques to produce the high fidelity groove profile necessary to achieve this performance. Application of this process has produced an initial pre-master that exhibits a radial (variable line spacing along the groove dimension), high density (> 6000 grooves/mm), laminar profile. This pre-master has been tested for diffraction efficiency at the BESSY II synchrotron light facility and diffracts up to 55 % of incident light into usable spectral orders. Furthermore, tests of spectral resolving power show that these gratings are capable of obtaining resolving powers well above 1300 ( λ/Δ λ) with limitations due to the test apparatus, not the gratings. Obtaining these results has provided confidence that this fabrication process is capable of producing off-plane reflection gratings for the next generation of X-ray observatories. [ABSTRACT FROM AUTHOR]

Over the past year, we have celebrated the tenth anniversary of the Chandra and XMM-Newton X-ray observatories. Both carry powerful, novel diffraction grating spectrometers, which have opened true X-ray spectroscopy for astrophysics. I will describe the design and operation of these instruments, as the background to some of the beautiful results they have produced. But these designs do not exhaust the versatility and essential simplicity of diffraction grating spectrometers, and I will discuss applications for the International X-ray Observatory IXO. [ABSTRACT FROM AUTHOR]

Abstract: Recently, it has been demonstrated that a shearing type interferometer, using precision silicon gratings, enables one to image the gradient of neutron phase shift through an object and retrieve the phase via a simple one-dimensional integration of the gradient. To fully explore this new technique for potential future cold neutron imaging stations at the National Institute of Standards and Technology and the Korea Atomic Energy Research Institute, we have developed a prototype phase imaging station at a monochromatic cold neutron beamline in the NCNR neutron guide hall. We have designed the silicon gratings for a neutron wavelength of 0.44nm and fabricated them using the state-of-the-art nanofabrication facility at the NIST Center for Nanoscale Science and Technology. Here we will discuss the experimental apparatus, as well as the recent experimental results obtained with this prototype apparatus. We will also present the data analysis method used for the phase retrieval, and discuss the accuracy of the method as well as the measurement sensitivity obtained using this method. [Copyright &y& Elsevier]

Discusses Mount Wilson Observatory diffraction gratings. Details of how engines capable of ruling hundreds of thousands of straight, parallel, equally spaced grooves within tolerances of only a few angstroms, have led to advances in fields as different as quantum mechanics and astrophysics; Details of how gratings and prisms work; Different type of ruling engines; Technological advances at the Mount Wilson Observatory. INSET: Distribution of gratings..

Diffraction gratings are famously associated with Henry Rowland of Johns Hopkins University but there were precursors. Although gratings were first made and used in Europe, reliable machines for ruling gratings were developed in the USA, and two men, Lewis Rutherfurd and William Rogers, tackled the problem before Rowland. Rutherfurd, a wealthy independent astronomer, designed and built the first screw-operated engine for ruling diffraction gratings, the fore-runner of almost all subsequent ruling engines. With it he and his assistant D. C. Chapman ruled many gratings which he generously distributed to practising scientists, thereby materially advancing the science of spectroscopy. Rogers was a Harvard astronomer who developed an interest in the ruling of fine lines on glass that led him to construct a ruling engine with which he investigated the causes of the errors in the rulings he had examined. He continued to seek improvements with a second engine designed for ruling diffraction gratings. He ceased developing this engine when Rowland's excellent gratings began to be available, concentrating instead on related problems to which he could apply the knowledge and skills he had gained, but his investigations assisted Rowland and other later ruling engine builders. This paper brings together what is known about the ruling engines of Rutherfurd and Rogers, their development, the gratings they produced, their quality and the work that was done with them, and assesses and compares their achievements and the impacts of the work of these two men.