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Creating supportive, caring environments for both staff and patients is a basic principle of holistic nursing practice and an increasingly important aspect of today's health care delivery system. The core of workforce engagement is the relationship of joy and meaning in the delivery of care of health care providers: joy in having a sense of accomplishment and significance in the work through processes leading to successful outcomes. Meaning refers to the sense of importance and impact in the daily work routines. Joy results with attainment and fulfilment from the meaning of the work.1 At Broward Health Imperial Point (BHIP), we live this philosophy.

Future astrophysical missions will require fabrication technology capable of producing high angular resolution x-ray optics. A full-shell direct fabrication approach using modern robotic polishing machines has the potential for producing high resolution, light-weight and affordable x-ray mirrors that can be nested to produce large collecting area. This approach to mirror fabrication, based on the use of the metal substrates coated with nickel phosphorous alloy, is being pursued at MSFC. The design of the polishing fixtures for the direct fabrication, the surface figure metrology techniques used and the results of the polishing experiments are presented.

Adjustable X-ray optics represent a potential enabling technology for simultaneously achieving large effective area and high angular resolution for future X-ray Astronomy missions. The adjustable optics employ a bimorph mirror composed of a thin (1.5 μm) film of piezoelectric material deposited on the back of a 0.4 mm thick conical mirror segment. The application of localized electric fields in the piezoelectric material, normal to the mirror surface, result in localized deformations in mirror shape. Thus, mirror fabrication and mounting induced figure errors can be corrected, without the need for a massive reaction structure. With this approach, though, film stresses in the piezoelectric layer, resulting from deposition, crystallization, and differences in coefficient of thermal expansion, can distort the mirror. The large relative thickness of the piezoelectric material compared to the glass means that even 100MPa stresses can result in significant distortions. We have examined compensating for the piezoelectric processing related distortions by the deposition of controlled stress chromium/iridium films on the front surface of the mirror. We describe our experiments with tuning the product of the chromium/iridium film stress and film thickness to balance that resulting from the piezoelectric layer. We also evaluated the repeatability of this deposition process, and the robustness of the iridium coating....

The multi-beam long trace profiler (MB-LTP) is under development at NASA's Marshall Space Flight Center. The traditional LTPs scans the surface under the test by a single laser beam directly measuring the surface figure slope errors. While capable of exceptional surface slope accuracy, the LTP single beam scanning has slow measuring speed. Metrology efficiency can be increased by replacing the single laser beam with multiple beams that can scan a section of the test surface at a single instance. The increase in speed with such a system would be almost proportional to the number of laser beams. The progress for a multi-beam long trace profiler development is presented.

The multi-beam long trace profiler (LTP) under development at NASA s Marshall Space Flight Center[1] is designed to increase the efficiency of metrology of replicated X-ray optics. The traditional LTP operates on a single laser beam that scans along the test surface to detect the slope errors. While capable of exceptional surface slope accuracy, the LTP single beam scanning has slow measuring speed. As metrology constitutes a significant fraction of the time spent in optics production, an increase in the efficiency of metrology helps in decreasing the cost of fabrication of the x-ray optics and in improving their quality. Metrology efficiency can be increased by replacing the single laser beam with multiple beams that can scan a section of the test surface at a single instance. The increase in speed with such a system would be almost proportional to the number of laser beams. A collaborative feasibility study has been made and specifications were fixed for a multi-beam long trace profiler. The progress made in the development of this metrology system is presented.

Future x-ray astronomical missions, similar to the proposed International X-ray Observatory (IXO), will utilize replicated mirrors to reduce both mass and production costs. Accurately figured and measured molds (called mandrels) - on which the mirror substrates are thermally formed, replicating the surface of the mandrels - are essential to enable these missions. The Optics Branches of the Goddard Space Flight Center (GSFC) and Marshall Space Flight Center (MSFC) have developed fabrication processes along with metrologies that yield high-precision mandrels; and through the SBIR program, they encourage small businesses to attack parts of the remaining problems. The Goddard full-aperture mandrel polisher (the MPM-500) has been developed to a level where mandrel surfaces match the 1.5 arcsec HPD level allocation in a 5 arcsec telescope program. This paper reviews this current technology and describes a pilot program to design a suite of machine tools and process parameters capable of producing many hundreds of these precision objects. A major challenge is to keep mid-spatial frequency errors below 2 nm rms - a severe specification; but we must also note the factors which work to our advantage: e.g., how the figure departs from a pure cone by only one micron, and how the demanding figure specifications which apply in the axial direction are relaxed by an order of magnitude in the azimuthal. Careful study of other large optical fabrication programs in the light of these challenges and advantages has yielded a realistic plan for the economical production of mandrels that meet program requirements in both surface and quantity.

In order to fulfill the angular resolution requirements and make the performance goals for future NASA missions feasible, it is crucial to develop instruments capable of fast and precise figure metrology of x-ray optical elements for further correction of the surface errors. The Long Trace Profilometer (LTP) is an instrument widely used for measuring the surface figure of grazing incidence X-ray mirrors. In the case of replicated optics designed for x-ray astronomy applications, such as mirrors and the corresponding mandrels have a cylindrical shape and their tangential profile is parabolic or hyperbolic. Modern LTPs have sub-microradian accuracy, but the measuring speed is very low, because the profilometer measures surface figure point by point using a single laser beam. The measurement rate can be significantly improved by replacing the single optical beam with multiple beams. The goal of this study is to demonstrate the viability of multi-beam metrology as a way of significantly improving the quality and affordability of replicated x-ray optics. The multi-beam LTP would allow one- and two-dimensional scanning with sub-microradian resolution and a measurement rate of about ten times faster compared to the current LTP. The design details of the instrument's optical layout and the status of optical tests will be presented.

The Marshall Grazing Incidence X-ray Spectrograph (MaGIXS) is a proposed sounding rocket experiment designed to observe spatially resolved soft X-ray spectra of the solar corona for the first time. The instrument is a purely grazing-incidence design, consisting of aWolter Type-1 sector telescope and a slit spectrograph. The telescope mirror is a monolithic Zerodur mirror with both the parabolic and hyperbolic surfaces. The spectrograph comprises a pair of paraboloid mirrors acting as a collimator and reimaging mirror, and a planar varied-line-space grating, with reflective surfaces operate at a graze angle of 2 degrees. This produces a flat spectrum on a detector covering a wavelength range of 6-24A (0.5-1.2 keV). The design achieves 20 mA spectral resolution (10 mA /pixel) and 5 arcsec spatial resolution (2.5 arcsec / pixel) over an 8-arcminute long slit. The spectrograph is currently being fabricated as a laboratory prototype. A flight candidate telescope mirror is also under development.

Platinum is being explored as an alternative to the sprayed boron nitride mandrel release coating under study at GSFC for the International X-ray Observatory (IXO). Two and three inch diameter, polished (PFS) and superpolished (SPFS) fused silica flat mandrels, were used for these tests. Pt was applied to the mandrels by DC magnetron sputtering. The substrate material was 400 micron thick D263 glass, the material which has been proposed for the IXO segmented optics. These substrates were placed on the mandrels and thermally cycled with the same thermal profile being used at GSFC in the development of the BN slumping for IXO. After the thermal cycle was complete, the D263 substrates were removed; new D263 substrates were placed on the mandrels and the process was repeated. Four thermal cycles have been completed to date. After initially coating the mandrels with Pt, no further conditioning was applied to the mandrels before or during the thermal cycles. The microroughness of the mandrels and of the D263 substrates was measured before and after thermal cycling. Atomic force microscopy (AFM) and 8 keV X-ray reflectivity data are presented.

The International X-ray Observatory (IXO) is designed to conduct spectroscopic, imaging, and timing studies of astrophysical phenomena that take place as near as in the solar system and as far as in the early universe. It is a collaborative effort of ESA, JAXA, and NASA. It requires a large X-ray mirror assembly with an unprecedented X-ray collection area and a suite of focal plane detectors that measure every property of each photon. This paper reports on our effort to develop the necessary technology to enable the construction of the mirror assembly required by IXO.

We have fabricated a precision full-cylinder stainless-steel mandrel at Marshall Space Flight Center. The mandrel is figured for a 30-cm diameter primary (paraboloid) mirror of an 840-cm focal-length Wolter-1 telescope. We have developed this mandrel for experiments in slumping.thermal forming at about 600 C.of glass mirror segments at Goddard Space Flight Center, in support of NASA's participation in the International X-ray Observatory (IXO). Precision turning of stainless-steel mandrels may offer a low-cost alternative to conventional figuring of fused-silica or other glassy forming mandrels. We report on the fabrication, metrology, and performance of this first mandrel; then we discuss plans and goals for stainless-steel mandrel technology.

We are developing grazing-incidence x-ray optics for astronomy. The optics are full-cylinder mirror shells fabricated using electroformed-nickel replication off super-polished mandrels. For space-based applications where weight is at a premium, very-thin-walled, light-weight mirrors are required. Such shells have been fabricated at MSFC with greater than 15 arcsec resolution. The challenge, however, is to preserve this resolution during mounting and assembly. We present here a status report on a mounting and alignment system currently under development at Marshall Space Flight Center to meet this challenge.

We are developing hard-x-ray optics using an electroformed-nickel-replication process off superpolished mandrels. To date, we have fabricated over 100 shells for our HERO balloon payload with typical angular resolutions in the 13-15 arcsec range. This paper discusses the factors currently limiting this resolution and various developments geared towards the production of higher-resolution optics.

We are developing grazing incidence x-ray optics for a balloon-borne hard-x-ray telescope (HERO). The HERO mirror shells are fabricated using electroform-nickel replication off super-polished cylindrical mandrels. One of the sources for mirror resolution error is departure of the shell figure from prescription. We have modified a Vertical-scan Long Trace Profilometer (VLTP) in order to measure the figure of the inner surface of the HERO mirror shells for diameters as small as 76 mm. Mirror alignment method and sources for systematic errors will be discussed. Comparison of figure metrology of the mandrel and the shells will be presented together with results from x-ray tests.

The long trace profiler (LTP) is the instrument of choice for the surface figure measurement of grazing incidence mirrors. The modification of conventional LTP, the vertical-scan LTP, capable of measuring the surface figure of replicated shell mirrors is now in operation at Marshall Space Flight Center. A few sources of systematic error for vertical-scan LTP are discussed. Status of systematic error reduction is reported.

SRS Technologies has made significant strides in the research and development of ultra-lightweight membrane optics for future imaging applications while conducting work with NASA Marshall Space Flight Center and the Air Force Research Lab. Thin film mirrors have been manufactured using surface replication casting of CP1, a polyimide material developed specifically for space applications. In the course of such efforts processing and manufacturing techniques have been developed to produce polyimide membranes with surface roughness below 1.5 nanometers rms and sub-wavelength thickness variation for both curved and flat membranes. This has led to the production of membranes optically flat to (lambda) /13 ((lambda) equals 633 nm) and curved membranes with figure error on the order of microns over half-meter diameters. This accuracy places such membranes within the demonstrated correctable range of several advanced wavefront correction technologies.

Stringent requirements of the SPARCLE telescope demanded testing of its individual elements through each step of fabrication, and complete metrology of the integrated telescope both at Helium-Neon and the operational two micron wavelengths.

In most cases, conventional interferometric methods can be used to test the figure of large spherical and flat optical components. There are, however, certain types of unconventional surfaces, such as those used in grazing incidence x-ray applications, that are nearly impossible to test by conventional means. These cylindrical aspheres are usually tested by some type of scanning optical profiler. We discuss the use of a versatile slope measuring scanning interferometer system, the Long Trace Profiler (LTP), in measuring the figure error of large surfaces, particularly those that have extremely long radii of curvature in the tangential direction. Use of this instrument in different configurations has permitted measurements to be made on cylindrical asphere segments that are over one meter long, on water-cooled high heat load mirrors in ultra high vacuum synchrotron beam lines under actual operating conditions, and on complete x-ray telescope mirror shells and mandrels that are mounted in a vertical configuration to minimize gravity sag errors. Each of these different configurations has its own particular advantages and shortcomings. The ultimate performance of the LTP depends upon the thermal stability of the local environment. We illustrate the effects that temperature variations on the order of plus or minus 0.1 degrees Celsius have on the errors in the measurement of a long radius sphere.