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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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A summary of radiation effects thresholds
Radiation effects thresholds of electronic equipment and structural materials - metals, polymers, ceramics, semiconductors, and electric components
NASA Facility for the Study of Space Radiation Effects
Space particulate radiation from the Van Allen belts, solar flares, galactic cosmic, and manmade sources have energies and fluxes which are capable of producing damage in space mission payloads. NASA - Langley Research Center, Hampton, Virginia, has initiated the construction of a ground-based Space Radiation Effects Laboratory which simulates most of the space particulate energy spectrum and which can be used in a radiation research program for minimizing or eliminating deleterious radiation effects. A 600-megaelectronvolt synchrocyclotron of variable energy and electron accelerators from 1 to 10 megaelectronvolts will be included in the laboratory for accelerated testing. The plan of the proposed test areas reflects the latest advances in the state of the art as it pertains to the engineering and basic experimental requirements in flexibility, radiation background levels, shielding, and isolation. The laboratory operational plan permits three Virginia institutions of higher learning to cooperate with the Langley Research Center in carrying out radiation programs.
NASA Space Radiation Effects Laboratory
Space radiation effects laboratory for simulation of particulate space radiation - NASA program
Radiation effects on semiconducting materials
Radiation effects on semiconductor materials
Transient radiation effects on thermocouples
Transient radiation effects on reactor thermocouples
Strong Sensitivity of Simulated Biomass Burning Aerosol Transport and Radiative Effects Over the South Atlantic to Carbonaceous Aerosol Aging and Particle Density
Biomass burning aerosol (BBA) impacts climate through aerosol‐cloud‐radiation interactions, but models disagree on the sign and magnitude of BBA radiative effects. We quantify the sensitivity of BBA radiative effects and transport to three BBA‐relevant processes and properties: parameterized oxidative aging of organic aerosol (OA), a combined change to black carbon (BC) density and the method for calculating aerosol refractive index, and reduction in OA density. We evaluate Unified Model simulations against two aircraft campaigns from summer 2017 over the Southeast Atlantic. The model generally performs well, such that discrepancies between the observational data sets may sometimes limit the precision of the evaluation. Our newly developed aging parameterization reproduces observed OA:BC mass ratios well and allows modeled OA:BC to decrease with smoke age, but increases bias in aerosol extinction and changes the BBA radiative effect little (+0.12 W m -2 ). We calculate aerosol refractive index using either a volume‐weighted component average or the Maxwell‐Garnett (MG) mixing assumption, which represents BC as small inclusions in a host material. Compared to MG mixing, the volume‐weighted average refractive index and reduced BC density increase aerosol absorption, substantially increasing the total BBA radiative effect (+2.66 W m -2 ) and amount of BBA transported across the ocean through BC self‐lofting. Reducing OA density to better match literature values changes the total BBA radiative effect by −1.96 W m -2 . Changes to direct radiative effects exceed changes to cloud radiative effects. Our findings emphasize the sensitivity of aerosol radiative effects and transport to these processes and properties, which we suggest could be improved in climate models.
Transient Radiation Effects on Thermocouples
Transient radiation effects on power reactor thermocouples determined at various levels of nuclear radiation
Ionizing radiation - effect on genetic transcription.
Ionizing radiation effects on DNA transcription in Escherichia coli cells and RNA messenger decay
Radiation effects on NERVA instrumentation.
Radiation effects on NERVA out-of-core instrumentation, discussing cryogenic temperature measurements and transducer measuring pressure at gamma heating rates
Engineering design of the space radiation effects laboratory
Engineering design of space radiation effects laboratory
Status report on the space radiation effects on the apollo mission. d- operational procedures for apollo dose radiation
Space radiation effects on Apollo mission - operational procedures for dose reduction
Summary of NERVA radiation effects tests at cryogenic temperatures.
NERVA radiation effects tests at cryogenic temperatures
Study of proton radiation effects on solar vehicle electronic system
Radiation effects on electronic equipment of solar spacecraft - shielding requirements
Summary of radiation effects on thermionic insulator materials
Radiation effects on thermionic insulator materials - evaluation of beryllia, alumina, thoria, zirconia, and yttria
Ionizing particle radiations effects and simulation consideration
Proton accelerator, electron accelerators, and beam transport system of NASA space radiation effects laboratory - transient, permanent, surface, and chemical radiation effects
A Self Consistent 2D Simulation of Coherent Synchrotron Radiation Effects on Beam Dynamics
An increasing interest in high quality and high current electron beams necessitates a thorough understanding and prediction of coherent synchrotron radiation effects. The self-interaction of charged particles in a beam undergoing synchrotron motion is a physically significant process that is all too often computationally intensive with very little analytical results to rely on for the general case. The coherent spectrum of this interaction is of utmost importance to the design of free electron lasers (FELs) and an accurate assessment is imperative for their design. This work presents a novel implementation to the numerical simulation of charged particle beams. The simulation is a self-consistent approach including the self-fields generated by the beam of which coherent synchrotron radiation effects are of primary interest. A particle-in-cell model is used where a planar beam sampled by point particles is deposited on an encompassing grid at each timestep. The electromagnetic fields are calculated on the grid using the retarded potentials according to causality. The electromagnetic forces from the fields are interpolated on each particle which in turn advance in time. The simulation is benchmarked against well-established results for coherent synchrotron radiation effects. In addition, studies are provided that show the convergence of simulation results for increasing resolution. A study into the transverse beam size effects on beam dynamics is performed as well as a proof of concept where the simulation is used by a genetic algorithm to optimize the design parameters of a beam lattice. The results of these studies in tandem verify the efficacy of the simulation for its practical use in accelerator design or the study of synchrotron radiation effects