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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Development of Operando Nuclear Magnetic Resonance Capabilities for Solid-State Battery Research

Mechanistic information regarding solid-solid interfaces in solid-state batteries remains elusive as its observation requires a non-destructive operando technique. Such a technique does not currently exist. Solid-state nuclear magnetic resonance (NMR) is uniquely suited to address this challenge as it is sensitive to chemistry, structure, and dynamics and can measure buried interfaces. However solid-state NMR requires high speed spinning of the sample at the ‘magic angle’ (MAS) to obtain adequate resolution. The metallic current collectors in a battery are detrimental to spinning in magnetic fields as they generate eddy currents which prevent spinning and dampen the NMR signal. Furthermore, the spinning nature of the MAS NMR experiment requires a wireless means of charging for operando capabilities. These challenges were addressed in this research and operando MAS NMR enabled by optical wireless charging was demonstrated. By limiting the size of the metallic components, we were able to spin a sample holder with electrical leads and a solid-state battery up to a few kilohertz, fast enough for high-resolution NMR. We achieved wireless charging by attaching a photovoltaic cell to the head of the NMR rotor and used a laser to transmit power to the photovoltaic cell. Demonstration of the optical wireless charging was performed by polarizing a liquid electrolyte during an operando MAS NMR measurement. This novel capability is a transformative technique for investigating the mechanistic electrochemical processes in solid-state samples.

25 ENERGY STORAGE↗
NASA NTRS1975

Development of a high efficiency thin silicon solar cell

Specific power output and radiation resistance characteristics developed for thin film silicon solar cells are reported. The technological base for fabricating these high efficiency cells and limitations of cell photovoltage are included. In addition, optical and electronic measurement instrumentation and mathematical analyses aids are included. Antireflection coatings for these cells are discussed.

Lindmayer, J.↗
NASA NTRS1983

The relationship between the X-ray and optical luminosities for QSOs

A study of simple models for the optical and X-ray luminosities of QSOs shows that a thick accretion disk around a black hole is consistent with the observed dependence of the X-ray luminosity L(x) on the optical luminosity L(opt) to the bth power, with b roughly in the range 0.5-0.8. The disk is expected to be thick since the sources are accreting at rates near the Edington limit. Using the model of McMillan, Lightman, and Cohn (1981) for the gas supply rate, the evolution of L(opt) is predicted to be proportional to t/t(0) to the -8/3 and that of L(x) is predicted to be proportional to t/t(0) to the -2.

Tucker, W. H.↗
NASA NTRS1983

Models of the hard X-ray spectrum of AM Herculis and implications for the accretion rate

Phenomenological fits to the hard X-ray spectrum of AM Herculis left unexplained the high equivalent width (0.8 + or - 0.1 keV) of Fe K alpha emission. A purely thermal origin implies a much steeper spectrum than was observed. With Monte Carlo calculations, scattering and fluorescent line production in a cold or partially ionized accretion column of hard X-rays emitted at the base were investigated. The strength of the iron emission and the flat spectral continuum can be explained by the effects of fluorescence and absorption within the accretion column and the surface of the white dwarf on a thermal X-ray spectrum. Thomson optical depths across the column in the range 0.2 to 0.7 are acceptable. The accretion rate and gravitational power can be deduced from the optical depth across the column, if the column size is known, and, together with the observed hard X-ray and polarized light luminosities, imply a lower limit for the luminosity in the UV to soft X-ray range, for which the observations give model-dependent values. Estimates of the column size differ by a factor of 40. Small spot sizes and low luminosities would be consistent with the soft component being the expected reprocessed bremsstrahlung and cyclotron radiation, although the constraint of matching the spectrum confines one to solutions with fluxes exceeding 20% the Eddington limits.

Swank, J. H.↗
NASA NTRS1984

Models of the hard X-ray spectrum of AM Herculis and implications for the accretion rate

Phenomenological fits to the hard X-ray spectrum of AM Hercules have failed to explain the high equivalent width (0.8 + or - 0.1 keV) of Fe K-alpha emission. The scattering and fluorescent line production in a cold or partially ionized accretion column of hard X-rays emitted at the base are investigated using the Monte Carlo method. It is shown that the Fe emission equivalent width observed in the spectrum of AM Her can be explained without resorting to an overabundance of Fe in the accreting material. For sufficient optical depth across the accretion column, equivalent widths of K-alpha emission even larger than the observed values can be obtained. The accretion rate and gravitational power can be deduced from the optical depth across the column, if the column size is known, and, together with the observed hard X-ray and polarized light luminosities, imply a lower limit for the luminosity in the UV to soft X-ray range, for which the observations give model-dependent values.

Swank, J. H.↗
NASA NTRS1990

Optical properties monitor: Experiment definition phase

The stability of materials used in the space environment will continue to be a limiting technology for space missions. The Optical Properties Monitor (OPM) Experiment provides a comprehensive space research program to study the effects of the space environment (both natural and induced) on optical, thermal and space power materials. The OPM Experiment was selected for definition under the NASA/OAST In-Space Technology Experiment Program. The results of the OPM Definition Phase are presented. The OPM experiment will expose selected materials to the space environment and measure the effects with in-space optical measurements. In-space measurements include total hemispherical reflectance total integrated scatter and VUV reflectance/transmittance. The in-space measurements will be augmented with extensive pre- and post-flight sample measurements to determine other optical, mechanical, electrical, chemical or surface effects of space exposure. Environmental monitors will provide the amount and time history of the sample exposure to solar irradiation, atomic oxygen and molecular contamination.

Wilkes, Donald R.↗
NASA NTRS2013

NASA Tech Briefs, September 2013

Topics include: ISS Ammonia Leak Detection Through X-Ray Fluorescence; A System for Measuring the Sway of the Vehicle Assembly Building; Fast, High-Precision Readout Circuit for Detector Arrays; Victim Simulator for Victim Detection Radar; Hydrometeor Size Distribution Measurements by Imaging the Attenuation of a Laser Spot; Quasi-Linear Circuit; High-Speed, High-Resolution Time-to-Digital Conversion; Li-Ion Battery and Supercapacitor Hybrid Design for Long Extravehicular Activities; Ultrasonic Low-Friction Containment Plate for Thermal and Ultrasonic Stir Weld Processes; High-Powered, Ultrasonically Assisted Thermal Stir Welding; Next-Generation MKIII Lightweight HUT/Hatch Assembly; Centrifugal Sieve for Gravity-Level-Independent Size; Segregation of Granular Materials; Ion Exchange Technology Development in Support of the Urine Processor Assembly; Nickel-Graphite Composite Compliant Interface and/or Hot Shoe Material; UltraSail CubeSat Solar Sail Flight Experiment; Mechanism for Deploying a Long, Thin-Film Antenna From a Rover; Counterflow Regolith Heat Exchanger; Acquisition and Retaining Granular Samples via a Rotating Coring Bit; Very-Low-Cost, Rugged Vacuum System; Medicine Delivery Device With Integrated Sterilization and Detection; FRET-Aptamer Assays for Bone Marker Assessment, C-Telopeptide, Creatinine, and Vitamin D; Multimode Directional Coupler for Utilization of Harmonic Frequencies from TWTAs; Dual-Polarization, Multi-Frequency Antenna Array for use with Hurricane Imaging Radiometer; Complementary Barrier Infrared Detector (CBIRD) Contact Methods; Autonomous Control of Space Nuclear Reactors; High-Power, High-Speed Electro-Optic Pockels Cell Modulator; Covariance Analysis Tool (G-CAT) for Computing Ascent, Descent, and Landing Errors; Enigma Version 12; Micrometeoroid and Orbital Debris (MMOD) Shield Ballistic Limit Analysis Program; Spitzer Telemetry Processing System; Planetary Protection Bioburden Analysis Program; Wing Leading Edge RCC Rapid Response Damage Prediction Tool (IMPACT2); ISSM: Ice Sheet System Model; Automated Loads Analysis System (ATLAS); Integrated Main Propulsion System Performance Reconstruction Process/Models. Phoenix Telemetry Processor; Contact Graph Routing Enhancements Developed in ION for DTN; GFEChutes Lo-Fi; Advanced Strategic and Tactical Relay Request Management for the Mars Relay Operations Service; Software for Generating Troposphere Corrections for InSAR Using GPS and Weather Model Data; Ionospheric Specifications for SAR Interferometry (ISSI); Implementation of a Wavefront-Sensing Algorithm; Sally Ride EarthKAM - Automated Image Geo-Referencing Using Google Earth Web Plug-In; Trade Space Specification Tool (TSST) for Rapid Mission Architecture (Version 1.2); Acoustic Emission Analysis Applet (AEAA) Software; Memory-Efficient Onboard Rock Segmentation; Advanced Multimission Operations System (ATMO); Robot Sequencing and Visualization Program (RSVP); Automating Hyperspectral Data for Rapid Response in Volcanic Emergencies; Raster-Based Approach to Solar Pressure Modeling; Space Images for NASA JPL Android Version; Kinect Engineering with Learning (KEWL); Spacecraft 3D Augmented Reality Mobile App; MPST Software: grl_pef_check; Real-Time Multimission Event Notification System for Mars Relay; SIM_EXPLORE: Software for Directed Exploration of Complex Systems; Mobile Timekeeping Application Built on Reverse-Engineered JPL Infrastructure; Advanced Query and Data Mining Capabilities for MaROS; Jettison Engineering Trajectory Tool; MPST Software: grl_suppdoc; PredGuid+A: Orion Entry Guidance Modified for Aerocapture; Planning Coverage Campaigns for Mission Design and Analysis: CLASP for DESDynl; and Space Place Prime.

Source record↗
NASA NTRSDate not supplied

Coherent Mode Decomposition for Kolmogorov Optical Turbulence in a Finite Aperture

An analysis of the coherent mode decomposition of an optical field after propagation through atmospheric turbulence is presented. The coherent modes represent an ideal basis by which to decompose the field for design of mode-limited optical systems. Due to rotational symmetry of the Fredholm integral operator for Kolmogorov optical turbulence, the coherent modes exhibit separable solutions classified by a radial and azimuthal mode index. The study of the coherent modes is then reduced to that of the radial functions determined by the coherence ratio and obscuration ratio. Analysis of the spectrum of eigenvalues yields sharp bounds on the efficiency of receivers using incoherent or coherent combining with mode-limited photonic devices in the presence of Kolmogorov turbulence. The effective number of modes needed to represent Kolmogorov optical turbulence is studied via the von Neumann entropy, purity, and largest eigenvalue, and the differences in the different definitions is discussed. The similarity of the coherent modes to linearly polarized (LP) fiber modes is quantified yielding a precise characterization of the maximum gain that can be achieved in mode-limited systems via mode shaping techniques. As a final application, a mode sorting technique is presented for optimally splitting power from atmospherically degraded light into a finite number of modes simultaneously maximizing total coupling efficiency and minimizing the difference in average power between channels.

free-space optical communication↗
NASA NTRSDate not supplied

Coherent Mode Decomposition for Kolmogorov Optical Turbulence in a Finite Aperture

An analysis of the coherent mode decomposition of an optical field after propagation through atmospheric turbulence is presented. The coherent modes represent an ideal basis by which to decompose the field for design of mode-limited optical systems. Using the rotational symmetry of the Fredholm integral operator for Kolmogorov optical turbulence, it is shown that the coherent modes exhibit separable solutions classified by radial and azimuthal quantum numbers. The study of the coherent modes is then reduced that of the radial functions determined by the aperture-coherence diameter ratio and obscuration ratio. Analysis of the spectrum of eigenvalues yields sharp bounds on the efficiency of receivers using incoherent or coherent combining with mode-limited photonic devices in the presence of Kolmogorov turbulence. The effective number of modes needed to represent Kolmogorov optical turbulence is studied via the von Neumann entropy, purity, and largest eigenvalue, and the differences in the different definitions is discussed. The similarity of the coherent modes to linearly polarized (LP) fiber modes is quantified yielding a precise characterization of the maximum gain that can be achieved in mode-limited systems via mode shaping techniques. As a final application, a mode sorting technique is presented for optimally splitting power from atmospherically degraded light into a finite number of modes simultaneously maximizing total coupling efficiency and minimizing the average and instantaneous power ratio between channels.

free-space optical communication↗
NASA NTRS2018

Optical Relay for Future NASA Geosynchronous Orbiting Satellite for High Data Rate Links to NASA User Missions

NASA is exploring options for its Next Generation Relay (NGR) architecture while the current Tracking Data Relay Satellite System (TDRSS) completes its mission. The plan is to start implementation of the NGR beginning around 2025. The new system of proposed relay satellites will greatly increase the data rates between low Earth orbiting (LEO) satellite missions and the NASA TDRSS relay satellites. This increase in data rates will allow an unprecedented increase in data throughput from the LEO satellite missions back to the principal investigators (PI). This can be accomplished at Ka-band frequencies with high order modulation or at optical frequencies using Differential Phase Shift Keying (DPSK). The first satellite in the next set of relay satellites will have to be backward compatible with current technology to support ongoing and planned missions. The new set of satellites will be launched over a 10-year period with design lifetimes of at least 15 years. To meet these requirements, we analyzed various architectures and designed both the communication payloads on the relay satellite and candidate payloads on the user spacecraft by utilizing optical heads already designed. From this analysis, a demonstration optical satellite named “the Next Generation Optical Relay Pathfinder” with Ka-band capabilities was proposed to be built and launched with the purpose of evaluating an integrated high-speed optical and Ka-band communication system. Given a cost limit for the demonstration satellite, various satellite configurations were developed by varying the number of optical communication payloads. The communication payload on the relay satellite consisted of three major sub-systems: 1) Optical communication payload, 2) Ka-band communication payload, 3) Digital processing and routing of signals. The size, mass (weight), and power (SWaP) of the communication payload and other sub-systems of the satellite were obtained. The NASA Glenn Research Center COMPASS team designed the Pathfinder satellite and performed a cost analysis for its build and launch. In this paper, we first describe the needs, drivers, and the associated challenges for the Next Generation Optical Relay Pathfinder to be capable of connecting multiple LEO and GEO satellites at high data rates. Second, we detail the concept of operations (ConOps) and the system architecture, including the satellite configurations considered, their attributes and limitations, and the size of the satellite needed for each configuration. Third, we provide a summary of the Next Generation Optical Relay Pathfinder satellite design trades and its key elements. Finally, we present the path needed for implementation and operations.

Warner, Joseph H. D.↗
DOE OSTI2024

Infrared nanoimaging and nanospectroscopy of electrochemical energy storage materials and interfaces

Electrochemical interfaces are central to the function and performance of energy storage devices. Thus, the development of new methods to characterize these interfaces, in conjunction with electrochemical performance, is essential for bridging the existing knowledge gaps and accelerating the development of energy storage technologies. Of particular need is the ability to characterize surfaces or interfaces in a non-destructive way with adequate resolution to discern individual structural and chemical building blocks. To this end, sub-diffraction-limit low-energy infrared optical probes that exploit near-field interactions within atomic force microscopy platforms, such as pseudoheterodyne nanoimaging, photothermal nanoimaging and nanospectroscopy, and nanoscale Fourier transform infrared spectroscopy, are all powerful emerging techniques. These are capable of non-destructive surface probing and imaging at nanometer resolution. This review outlines recent efforts to characterize ex situ, in situ, and operando electrode materials and electrochemical interfaces in rechargeable batteries with these advanced infrared near-field probes.

25 ENERGY STORAGE↗
NASA NTRS2001

Performance Evaluation of Titanium Ion Optics for the NASA 30 cm Ion Thruster

The results of performance tests with titanium ion optics were presented and compared to those of molybdenum ion optics. Both titanium and molybdenum ion optics were initially operated until ion optics performance parameters achieved steady state values. Afterwards, performance characterizations were conducted. This permitted proper performance comparisons of titanium and molybdenum ion optics. Ion optics' performance A,as characterized over a broad thruster input power range of 0.5 to 3.0 kW. All performance parameters for titanium ion optics of achieved steady state values after processing 1200 gm of propellant. Molybdenum ion optics exhibited no burn-in. Impingement-limited total voltages for titanium ion optics where up to 55 V greater than those for molybdenum ion optics. Comparisons of electron backstreaming limits as a function of peak beam current density for molybdenum and titanium ion optics demonstrated that titanium ion optics operated with a higher electron backstreaming limit than molybdenum ion optics for a given peak beam current density. Screen grid ion transparencies for titanium ion optics were as much as 3.8 percent lower than those for molybdenum ion optics. Beam divergence half-angles that enclosed 95 percent of the total beam current for titanium ion optics were within 1 to 3 deg. of those for molybdenum ion optics. All beam divergence thrust correction factors for titanium ion optics were within 1 percent of those with molybdenum ion optics.

Soulas, George C.↗
NASA NTRS1999

Phase-Shifted Laser Feedback Interferometry

Phase-shifted, laser feedback interferometry is a new diagnostic tool developed at the NASA Lewis Research Center under the Advanced Technology Development (ATD) Program directed by NASA Headquarters Microgravity Research Division. It combines the principles of phase-shifting interferometry (PSI) and laser-feedback interferometry (LFI) to produce an instrument that can quantify both optical path length changes and sample reflectivity variations. In a homogenous medium, the optical path length between two points is the product of the index of refraction and the geometric distance between the two points. LFI differs from other forms of interferometry by using the laser as both the source and the phase detector. In LFI, coherent feedback of the incident light either reflected directly from a surface or reflected after transmission through a region of interest will modulate the output intensity of the laser. The combination of PSI and LFI has produced a robust instrument, based on a low-power helium-neon (HeNe) gas laser, with a high dynamic range that can be used to measure either static or oscillatory changes of the optical path length. Small changes in optical path length are limited by the fraction of a fringe that can be measured; we can measure nonoscillatory changes with a root mean square (rms) error of the wavelength/1000 without averaging.

Ovryn, Benjie↗
NASA NTRS2018

Development of Transition Edge Sensor Detectors Optimized for Single-Photon Spectroscopy in the Optical and Near-Infrared

The search for biosignatures in the atmospheres of exoplanets will be a key focus of future space telescopes that operate in the ultraviolet, visible, and near-infrared bands. Detection of biosignatures requires an instrument with moderate spectral resolving power (R ~ 100) and a large bandwidth (~ 400 nm – ~ 1.8 µm). Additionally, biosignature detection is a photon-starved science; instruments designed for these measurements would ideally combine high optical efficiency with quantum-limited photon detectors (i.e., detectors that exhibit zero dark current). In this work, we report on our efforts to develop energy resolving transition edge sensor (TES)-based detectors designed for biosignature detection. TESs operated as microcalorimeters are compelling detectors for this application. Unlike semiconductor detectors, TESs eliminate the need for dispersive optics and are truly single photon detectors – fundamental TES noise yields uncertainty in the energies of detected photons, not in the number of detected photons. We introduce TESs designed for this application and discuss the path toward realizing a TES-based dispersionless spectrometer optimized for biosignature detection.

Instrumentation and Photography↗
NASA NTRS2011

Ultra-Sensitive Transition-Edge Sensors for the Background Limited Infrared/Sub-mm Spectrograph (BLISS)

We report progress in fabricating ultra-sensitive superconducting transition-edge sensors (TESs) for BLISS. BLISS is a suite of grating spectrometers covering 35-433 micron with R approx. 700 cooled to 50 mK that is proposed to fly on the Japanese space telescope SPICA. The detector arrays for BLISS are TES bolometers readout with a time domain SQUID multiplexer. The required noise equivalent power (NEP) for BLISS is NEP = 10(exp -19) W/Hz(exp 1/2) with an ultimate goal of NEP= 5 x 10(exp -20) W/Hz(exp 1/2) to achieve background limited noise performance. The required and goal response times are tau = 150 ms and tau = 50ms respectively to achieve the NEP at the required and goal optical chop frequency 1-5 Hz. We measured prototype BLISS arrays and have achieved NEP = 6 x 10(exp -18) W/Hz(exp 1/2) and tau = 1.4 ms with a Ti TES (T(sub C) = 565 mK) and NEP approx. 2.5 x 10(exp -19) W/Hz(exp 1/2) and tau approximates 4.5 ms with an Ir TES (T(sub C) = 130 mK). Dark power for these tests is estimated at 1-5 fW.

transition-edge sensors (TESs)↗
NASA NTRS1995

Stress Tuning of Laser Crystals

The topic of stress tunable laser crystals is addressed in this study with the purpose of determining the piezo-optic coefficients of a new laser material. This data was collected using a quadruple pass birefringence technique because of its high degree of sensitivity relative to the other methods examined including fringe shift analysis using a Mach-Zender interferometer. A green He-Ne laser was passed through a light chopper and Glan-Thompson prism before entering a crystal of Erbium doped Yttrium Aluminum Garnet (Er:YAG) (used in order to validate the experimental technique). The Er:YAG crystal is mounted in a press mechanism and the laser is quadruple passed through test specimen before being returned through the prism and the orthogonally polarized portion of the beam measured with a optical sensor. At a later stage, the Er:YAG crystal was replaced with a new crystal in order to determine the piezo-optic coefficients of this uncharacterized material. The applied load was monitored with the use of a 50 lb. load cell placed in line with the press. Light transmission readings were taken using a lock-in amplifier while load cell measurements were taken with a voltmeter from a 5 volt, 0.5 amp power supply. Despite the fact that an effective crystal press damping system was developed, size limitations precluded the use of the complete system. For this reason, data points were taken only once per full turn so as to minimize the effect of non uniform load application on the collected data. Good correlation was found in the transmission data between the experimentally determined Er:YAG and the previously known peizo-optic constants of non-doped crystal with which it was compared. The variation which was found between the two could be accounted for by the aforementioned presence of Erbium in the experimental sample (for which exact empirical data was not known). The same test procedure was then carried out on a Yttrium Gallium Aluminum garnet (YGAG) for the purpose of establishing values of its unknown piezo-optic constant tensor using experimentally collected transmission data. Significant variation between the piezo-optic constants of YAG and YGAG crystals was found however, the excellent data correlation of separate experimental runs carried out on the YGAG sample demonstrates the validity of these results. The data collected during the stressing of the YGAG was of high quality, however the amount of data collected was somewhat limited by a fracture of YGAG specimen which undoubted altered the crystalline lattice structure and hence precluded any further testing.

Carty, Atherton A.↗
DOE OSTI2023

Disorder, interactions, and their interplay in novel narrow-gap Dirac materials and Weyl semimetals

Progress of the modern day condensed matter physics is to a large extent driven by the synthesis of new materials, advances in their experimental characterization and theoretical description. Recent discoveries of novel gapless Weyl semimetals, such as NaBi,CdAs, and BiTe-based films, in which magnetic dopants essentially suppress the gap, have added to the family of graphene and topological insulators actively investigated over the past decade. With the field of novel semimetals rapidly maturing, its focus necessarily shifts from demonstrations of the feasibility of such materials to their quantitative characterization. While the transport and optical properties of graphene and topological insulators are well captured within the picture of free non-interacting electrons, gapless 3D Weyl semimetals and narrow-gap 2D semiconductors with Dirac spectrum are known to be extremely susceptible to disorder and electron-electron interactions. This susceptibility obscures the manifestations of nontrivial band structure -- like quantum anomalous Hall effect -- of the new topological materials. Among particular projects to be addressed are: 1) optical conductivity of 3D gapless Dirac fermions in the presence of smooth disorder, 2) interplay of disorder and Coulomb interactions in the spectral properties of such fermions, 3) formation and structure of the impurity band with Coulomb supercritical clusters, 4) Coulomb interaction-driven renormalization of the electron spectrum and of the transport response in the presence of strong magnetic field, 5) instanton approach to the disorder-induced fluctuation states in zero-gap 3D materials, and 6) the role of disorder in quantum anomalous Hall effect. The proposal relies upon the investigators' previous broad expertise in interacting and disordered electron systems. The methods to be employed include perturbative diagrammatic technique, non-perturbative instanton and self-consistent approximations, hydrodynamics of electron liquid. Both analytical as well as numerical approaches are to be employed. The anticipated broader outcome of the proposal includes gaining an in-depth understanding of the interplay of the disorder and interactions under the conditions when this interplay has the most dramatic impact on observables. Traditionally, interaction effects are among the most challenging and interesting problems of condensed matter physics. Similarly, disordered systems typically present very difficult but extremely rich problems in the description of various materials. Importantly, understanding the spectral and transport properties of such materials not only presents the fundamental objective, but is also of particular interest for many applications, such as computation, memory, optics, plasmonics. In particular realization of the quantum anomalous Hall effect may lead to the development of low-power-consumption electronics. Indeed, a major constraint for practical use of the quantum Hall effect is limited by the requirement of the quantizing magnetic field. At the same time, the quantum anomalous Hall effect samples exhibit non-dissipative edge quantum transport in a zero magnetic field.

36 MATERIALS SCIENCE↗
NASA NTRS1989

Optical properties monitor: Experiment definition phase

The stability of materials used in the space environment will continue to be a limiting technology for space missions. The Optical Properties Monitor (OPM) Experiment provides a comprehensive space research program to study the effects of the space environment-both natural and induced-on optical, thermal and space power materials. The OPM Experiment was selected for definition under the NASA/OAST In-Space Technology Experiment Program. The results of the OPM Definition Phase are presented. The OPM Experiment will expose selected materials to the space environment and measure the effects with in-space optical measurements. In-space measurements include total hemispherical reflectance total integrated scatter and VUV reflectance/transmittance. The in-space measurements will be augmented with extensive pre- and post-flight sample measurements to determine other optical, mechanical, electrical, chemical or surface effects of space exposure. Environmental monitors will provide the amount and time history of the sample exposure to solar irradiation, atomic oxygen and molecular contamination.

Wilkes, Donald R.↗