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NASA NTRS2008

Performance of a Borehole X-ray Fluorescence Spectrometer for Planetary Exploration

We have designed and constructed a borehole X-ray Fluorescence Spectrometer (XRFS) as part of the Mars Subsurface Access program [1]. It can be used to determine the composition of the Mars regolith at various depths by insertion into a pre-drilled borehole. The primary requirements and performance metrics for the instrument are to obtain parts-per-million (ppm) lower limits of detection over a wide range of elements in the periodic table (Magnesium to Lead). Power consumption during data collection was also measured. The prototype instrument is complete and preliminary testing has been performed. Terrestrial soil Standard Reference Materials were used as the test samples. Detection limits were about 10 weight ppm for most elements, with light elements being higher, up to 1.4 weight percent for magnesium. Power consumption (excluding ground support components) was 12 watts.

Kelliher, Warren C.↗

NASA NTRS1991

Composite video and graphics display for multiple camera viewing system in robotics and teleoperation

A system for real-time video image display for robotics or remote-vehicle teleoperation is described that has at least one robot arm or remotely operated vehicle controlled by an operator through hand-controllers, and one or more television cameras and optional lighting element. The system has at least one television monitor for display of a television image from a selected camera and the ability to select one of the cameras for image display. Graphics are generated with icons of cameras and lighting elements for display surrounding the television image to provide the operator information on: the location and orientation of each camera and lighting element; the region of illumination of each lighting element; the viewed region and range of focus of each camera; which camera is currently selected for image display for each monitor; and when the controller coordinate for said robot arms or remotely operated vehicles have been transformed to correspond to coordinates of a selected or nonselected camera.

Diner, Daniel B.↗

NASA NTRS1993

Composite video and graphics display for camera viewing systems in robotics and teleoperation

Diner, Daniel B.↗

NASA NTRS2020

Effect of Pressure on the Activity Coefficients of Au and Other Siderophile Elements in Liquid Fe-Si Alloys

Light elements can alloy into the iron cores of terrestrial planetary bodies. It is estimated that the Earth’s core contains ~10% of a light element, most likely a combination of S, C, Si, and O with Si probably being the most abundant. Si dissolved into Fe metal liquids can have a significant influence on the activity coefficients of siderophile elements, and thus the partitioning behavior of those elements between the core and mantle. Many of these elements have been investigated extensively at ambient pressure, and studies up to 1 GPa are becoming more common, but few have been studied at pressures above this. The formation of the Earth’s core has been estimated to have formed at pressures between 40-60 GPa, so investigating the effect pressure has on Si’s influence on siderophile element partitioning is important for modeling core formation in the Earth and smaller planets. Pressure is well known to influence volumetric properties of metallic and silicate liquids, and oxygen fugacity (e.g., [10,11]), but less is known about its effect on activity coefficients (e.g., [12]). Some activity coefficients depend strongly upon the Si content of Fe liquids, and the concentration of siderophile elements such as P, Sb, and As in the terrestrial mantle is easily influenced by dissolved Si in the core. Thus, isolating the effect of pressure on activity coefficients in general is critical in quantitative analysis of core formation models. In this work, we investigate the effect variable Si content has on the partitioning of Au between Fe metal and silicate melt at 10 GPa and 2373 K, with the intention of comparing the behavior to that already investigated at lower pressures. In addition, P, V, Mn, Ga, Zn, Cd, Sn, W, Pb, and Nb were also measured and could thus be included in the assessment of potential pressure effects.

Righter, K.↗

DOE OSTI2024

Cosmic neutrino decoupling and its observable imprints: insights from entropic-dual transport

Abstract Very different processes characterize the decoupling of neutrinos to form the cosmic neutrino background (CνB) and the much later decoupling of photons from thermal equilibrium to form the cosmic microwave background (CMB). The CνB emerges from the fuzzy, energy-dependent neutrinosphere and encodes the physics operating in the early universe in the temperature rangeT∼ 10 MeV toT∼ 10 keV. This is the epoch where beyond Standard Model (BSM) physics, especially in the neutrino sector, may be influential in setting the light element abundances, the necessarily distorted fossil neutrino energy spectra, and other light particle energy density contributions. Here we use techniques honed in extensive CMB studies to analyze the CνB as calculated in detailed neutrino energy transport and nuclear reaction simulations of the protracted weak decoupling and primordial nucleosynthesis epochs. Our moment method, relative entropy, and differential visibility approach can leverage future high precision CMB and light element primordial abundance measurements to provide new insights into the CνB and any BSM physics it encodes. We demonstrate that the evolution of the energy spectrum of the CνB throughout the weak decoupling epoch is accurately captured in the Standard Model by only three parameters per species, a non-trivial conclusion given the deviation from thermal equilibrium and the impact of the decrease of electron-positron pairs. Furthermore, we can interpret each of the three parameters as physical characteristics of a non-equilibrium system. Though the treatment presented here makes some simplifying assumptions including ignoring neutrino flavor oscillations, the success of our compact description within the Standard Model motivates its use also in BSM scenarios. We further demonstrate how observations of primordial light element abundances can be used to place constraints on the CνB energy spectrum, deriving response functions that can be applied for general deviations from a thermal spectrum. Combined with the description of those deviations that we develop here, our methods provide a convenient and powerful framework to constrain the impact of BSM physics on the CνB.

Astronomy & Astrophysics↗

NASA NTRS2003

Light Lithophile Elements in Natural and Experimental Phases in Martian Basalts: Implications for the Degassing of Water from Martian Magmas

Lentz et al. argued that zoning trends in light lithophile elements (LLE) in pyroxene in Shergotty and Zagami are evidence for the degassing of magmatic water. We tested this inference by obtaining: additional LLE analyses of Shergotty and Zagami pyroxene; analyses of Pasamonte pyroxene; and silicate and phosphate partition coefficients for B and Li for martian magma and mineral compositions.

Herd, C. D. K.↗

NASA NTRS1977

Effects of radiation upon the light-sensing elements of the retina as characterized by scanning electron microscopy

A model system using Necturus maculosus, the common mudpuppy, was established for evaluating effects of radiation upon the light-sensing elements of the retina. Accelerated heavy ions of helium and neon from the Berkeley Bevalac were used. A number of criteria were chosen to characterize radiation damage by observing morphological changes with the scanning electron microscope. The studies indicated retina sensitivity to high-LET (neon) particles at radiation levels below 10 rads (7 particles per visual element) whereas no significant effects were seen from fast helium ions below 50 rads.

Malachowski, M. J.↗

NASA NTRSDate not supplied

Initial analysis of “stone” size Ryugu samples: current status

As a part of the initial analysis of the Ryugu samples, we perform a variety of analyses of millimeter-sized "stones". Our goals are to elucidate the entire formation process of C-type asteroid Ryugu from the viewpoint of petrology and mineralogy ande obtain necessary information by sample analysis, and then simulate the formation of Ryugu based on the evidencef obtained rom sample analysis. Eighteen stones (8 from Room A and 10 from Room C) were received from the ISAS curation facility on June 1, 2021, and brought into a fully nitrogen-displaced glove box at Tohoku University. At the same time, we also received the powder samples from Room A and Room C. To completely block the atmosphere from leaking into the container, all samples were put in the sample transport containers prepared by ISAS, transferred from the main chamber to the glovebox at ISAS, and then all containers were completely sealed in plastic bags with moisture and oxygen absorbers. No moisture or oxygen was detected when the bags were opened in the glove box at Tohoku University, so it was confirmed that there was no exposure to the atmosphere during transport. To date, a number of analyses have been carried out successfully and almost on schedule. The analysis started with the measurement of reflectance spectra, which are sensitive to atmospheric oxidation, hydroxylation, and adsorbed water. The visible, near-infrared, and mid-infrared reflectance spectra were measured while the samples were kept airtight. The spectra of powder samples and stone samples (as aggregates and as single stone) were successfully obtained. A major feature of the stone team's analysis is the use of synchrotron radiation facilities around the world. Since this analysis is non-destructive, stone samples whose reflectance spectra were measured were sent to KEK, SPring-8, ESRF (France), SOLEIL (France), DESY (Germany), and APS (USA). Using these synchrotron radiation facilities, high spatial resolution and sensitivity XRD, STXM, XANES, CT [1], IR-CT, FT-IR [2, 3], XRF, and Mössbauer analyses were performed. Most of the analyses were carried out under air-tight conditions on the stone samples and the particulates separated from the stone samples. These analyses allowed us to determine the three-dimensional distribution of minerals and elements, redox state, density and porosity of the stone samples. Furthermore, as a characteristic analysis of the stone team, light elemental analysis using negative Muon was performed at the MLF facility of J-PARC with an exceptionally long allocation of machine time. This is the only non-destructive method to measure the concentration of light elements in the whole (not the surface) of stone samples. Because the characteristic X-rays produced by muon irradiation are much higher in energy than the fluorescent X-rays produced by X-ray irradiation, there is little effect of self-absorption by the sample, and therefore, the concentration of light elements such as carbon, oxygen, and Na in the entire "stone" sample can be determined. Some stone samples are currently being measured for heat and strength physical properties in order to understand the physical properties of asteroid Ryugu. The data obtained from these measurements are useful for interpreting the remote-sensing data data taken from the surface layer of the asteroid Ryugu [4-7]. It is also important for understanding the behavior of the Ryugu material during impact events. The surfaces of many stone samples were observed by electron microscopy and other techniques, especially on natural “flat” surfaces formed on 5 stomes. As a result, characteristric mineral aggregates formed by the reactions with water and characteiristic impact features were observed on some of the samples. Based on the observations of surfaces and the synchrotron measurements of the whole stones, important objects such as characteristic structures and specific crystal aggregates for understanding the formation history of the asteroid were identified, and these parts were separated from the stone samples using an Xe beam (pFIB) and analyzed by various methods including transmission electron microscopy and synchrotron radiation analysis. Many stone samples, from which important objects have been separated, are embedded in epoxy resin and cut to produce many polished sections. Electron microscopy and spectroscopic measurements of the polished surfaces are being carried out to reveal the detailed mineralogical properties and elemental distribution inside the stone samples. In the fall, machine time for synchrotron radiation will begin, and we plan to analyze single crystals and characteristic objects separated from the stone samples.

Tomoki Nakamura↗

NASA NTRS2018

Computer Controlled Solid State Lighting Assembly to Emulate Diurnal Cycle and Improve Circadian Rhythm Control

A light system can simultaneously emulate more than one different diurnal cycle to individually improve circadian rhythm control for more than one observer by having each light fixture autonomously self-controlled. Each light fixture is mountable in respective locations to individually treat respective observers. Each light fixture includes one or more light elements mounted to a housing and are controllable to emit a selected light intensity at a selected light temperature. A micro controller is contained in the housing and includes memory containing instructions for one or more automatic diurnal cycle protocols. The micro controller is in communication with the memory and the one or more light elements to execute the instructions to configure the light fixture to vary the light intensity and the light temperature of the emitted light.

Holbert, Eirik↗

NASA NTRS2006

Sulfur in Earth's Mantle and Its Behavior During Core Formation

The density of Earth's outer core requires that about 5-10% of the outer core be composed of elements lighter than Fe-Ni; proposed choices for the "light element" component of Earth's core include H, C, O, Si, S, and combinations of these elements [e.g. 1]. Though samples of Earth's core are not available, mantle samples contain elemental signatures left behind from the formation of Earth's core. The abundances of siderophile (metal-loving) elements in Earth's mantle have been used to gain insight into the early accretion and differentiation history of Earth, the process by which the core and mantle formed, and the composition of the core [e.g. 2-4]. Similarly, the abundance of potential light elements in Earth's mantle could also provide constraints on Earth's evolution and core composition. The S abundance in Earth's mantle is 250 ( 50) ppm [5]. It has been suggested that 250 ppm S is too high to be due to equilibrium core formation in a high pressure, high temperature magma ocean on early Earth and that the addition of S to the mantle from the subsequent accretion of a late veneer is consequently required [6]. However, this earlier work of Li and Agee [6] did not parameterize the metalsilicate partitioning behavior of S as a function of thermodynamic variables, limiting the different pressure and temperature conditions during core formation that could be explored. Here, the question of explaining the mantle abundance of S is revisited, through parameterizing existing metal-silicate partitioning data for S and applying the parameterization to core formation in Earth.

Chabot, Nancy L.↗

NASA NTRS1998

Analysis of New Orion Gamma Ray Data and Monte Carlo Simulations of BATSE Gamma Ray Bursts

These studies were stimulated by the reported COMPTEL detection of nuclear gamma ray line emission from the Orion star formation region. Although the observation have very recently been retracted, the detailed analyses that we carried out clearly showed that the low energy cosmic rays that would have been required to explain the reported fluxes were exceedingly restrictive and thus highly improbable. Moreover, these studies proved to be the trigger for very productive new work. In particular, they led us into carefully re-examining the problem of the origin of the light elements, Li, Be and B, where we showed that the light elements could, in fact, be produced primarily by Galactic cosmic rays and did not require an unobserved low energy cosmic ray source , as had been suggested. We further showed that the observed abundances of Be and B in old halo stars contradicted the common belief that the Galactic cosmic rays were accelerated out of the well mixed interstellar medium, and required instead that they be accelerated out of freshly synthesized matter from supernovae. This work, in turn, led us to propose a new origin of Galactic cosmic rays from the refractory grains in supernova enriched cores of superbubbles.

Lingenfelter, Richard E.↗

NASA NTRS1998

Theoretical Studies in Gamma-Ray Astrophysics

These studies were stimulated by the reported COMPTEL detection of nuclear gamma ray line emission from the Orion star formation region. Although the observation have very recently been retracted, the detailed analyses that we carried out clearly showed that the low energy cosmic rays that would have been required to explain the reported fluxes were exceedingly restrictive and thus highly improbable. More importantly, these studies proved to be the trigger for very productive new work. In particular, they led us into carefully re-examining the problem of the origin of the light elements, Li, Be and B, where we showed that the light elements could, in fact, be produced primarily by Galactic cosmic rays and did not require an unobserved low energy cosmic ray source , as had been suggested. We further showed that the observed abundances of Be and B in old halo stars contradicted the common belief that the Galactic cosmic rays were accelerated out of the well mixed interstellar medium, and required instead that they be accelerated out of freshly synthesized matter from supernovae. This work, in turn, led us to propose a new origin of Galactic cosmic rays from the refractory grains in supernova enriched core of superbubbles, which is now the subject of our on-going research under a new grant from the Astrophysics Theory Program.

Lingenfelter, Richard E.↗

NASA NTRS1975

Lunar Science Conference, 6th, Houston, Tex., March 17-21, 1975, Proceedings. Volume 2 - Chemical and isotopic studies

The chemical compositions of lunar rocks and soils are examined, taking into account sulfur abundances and distributions in mare basalts and their source magmas, lithophile trace and major elements in Apollo 16 and 17 lunar samples, the role of vaporization processes in lunar rock formation, chemical studies of the lunar regolith with emphasis on zirconium and hafnium, a model for the lunar anorthositic gabbro, and trace-element chemistry and reducing capacity of size fractions from the Apollo 16 regolith. Other topics considered are related to lunar chronology, volatile meteoritic elements, isotopic studies, light element geochemistry, and agglutinates and regolith processes. Attention is given to meteoritic material in four terrestrial meteorite craters, the state of meteoritic material on the moon, volatile elements in Allende inclusions, oxygen isotope fractionation in Apollo 17 rocks, cosmogenic isotope production in Apollo deep-core samples, and the effects of exposure conditions on cosmic-ray records in lunar rocks.

Merrill, R. B.↗

NASA NTRS1979

The elemental and isotopic abundances of H, C, N, O in comets

The elemental abundances of light elements in comets is discussed by considering gas and dust separately. It is noted that the icy conglomerate model of the nucleus (Whipple, 1957) has been confirmed, and that the dust-to-gas mass ratio has been estimated within a factor of two for two recent comets. It is found that the total amount of oxygen available is also nominally in solar abundance; this implies that the oxygen of the solar nebula has probably been quantitatively bound in compounds that have been completely condensed and accreted in cometary nuclei. In addition, the amount of hydrogen is clearly depleted by a factor of 2,000, suggesting that the only hydrogen present is that linked in molecular compounds of H, C, N and O.

Delsemme, A. H.↗

NASA NTRS2011

Calibration of the MSL/ChemCam/LIBS Remote Sensing Composition Instrument

The ChemCam instrument suite on board the 2011 Mars Science Laboratory (MSL) Rover, Curiosity, will provide remote-sensing composition information for rock and soil samples within seven meters of the rover using a laser-induced breakdown spectroscopy (LIBS) system, and will provide context imaging with a resolution of 0.10 mradians using the remote micro-imager (RMI) camera. The high resolution is needed to image the small analysis footprint of the LIBS system, at 0.2-0.6 mm diameter. This fine scale analytical capability will enable remote probing of stratigraphic layers or other small features the size of "blueberries" or smaller. ChemCam is intended for rapid survey analyses within 7 m of the rover, with each measurement taking less than 6 minutes. Repeated laser pulses remove dust coatings and provide depth profiles through weathering layers, allowing detailed investigation of rock varnish features as well as analysis of the underlying pristine rock composition. The LIBS technique uses brief laser pulses greater than 10 MW/square mm to ablate and electrically excite material from the sample of interest. The plasma emits photons with wavelengths characteristic of the elements present in the material, permitting detection and quantification of nearly all elements, including the light elements H, Li, Be, B, C, N, O. ChemCam LIBS projects 14 mJ of 1067 nm photons on target and covers a spectral range of 240-850 nm with resolutions between 0.15 and 0.60 nm FWHM. The Nd:KGW laser is passively cooled and is tuned to provide maximum power output from -10 to 0 C, though it can operate at 20% degraded energy output at room temperature. Preliminary calibrations were carried out on the flight model (FM) in 2008. However, the detectors were replaced in 2009, and final calibrations occurred in April-June, 2010. This presentation describes the LIBS calibration and characterization procedures and results, and details plans for final analyses during rover system thermal testing, planned for early March.

Wiens, R. C.↗

NASA NTRS2023

The Nature of Insoluble Organic Matter in Sutter’s Mill and Murchison Carbonaceous Chondrites: Testing the Effect of X-ray Computed Tomography (XCT) and Exploring Parent Body Organic Molecular Evolution

This study analyzed samples of the Murchison and Sutter’s Mill carbonaceous chondrite meteorites in support of the future analysis of samples returned from the asteroid (10155) Bennu by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission. Focusing specifically on the insoluble organic matter (IOM), this study establishes that a total of 1.3 g of bulk sample from a single chondritic meteorite is sufficient to obtain a wide range of cosmochemical information, including light element analysis (H, C, and N), isotopic analysis (D/H, 13 C/ 12 C, and 15 N/ 14 N), and X-ray fluorescence spectroscopy for major elemental abundances. IOM isolated from the bulk meteorite samples was analyzed by light element and isotopic analysis as described above, 1 H and 13 C solid-state nuclear magnetic resonance spectroscopy, Raman spectroscopy, and complete noble gas analyses (abundances and isotopes). The samples studied included a pair from Murchison (CM2), one of which had been irradiated with high-energy X-rays in the course of computed tomographic imaging. No differences between the irradiated and non-irradiated Murchison samples were observed in the many different chemical and spectroscopic analyses, indicating that any X-ray–derived sample damage is below levels of detection. Elemental, isotopic, and molecular spectroscopic data derived from IOM isolated from the Sutter’s Mill sample reveals evidence that this meteorite falls into the class of heated CM chondrites.

planetary science↗

DOE OSTI2026

Three-nucleon lepton-number-violating potentials in chiral effective field theory and their matrix elements in light nuclei

Here, we derive the three-nucleon neutrinoless double-𝛽 decay potential in a Δ-full chiral effective field theory through next-to-next-to-next-to leading order in Weinberg's power counting. The matrix elements of the resulting operators are computed in light nuclei using variational Monte Carlo with wave functions constructed from the Norfolk family of nuclear interactions. We find that three-nucleon corrections induce a modest quenching of the total nuclear matrix elements. We discuss model dependencies and the potential impact of these corrections on the sensitivity of experimental programs to probe lepton number violating parameters. These results provide a benchmark for many-body methods capable of reaching heavier nuclei of experimental interest.

Chambers-Wall, Graham [Washington University, St. ↗

DOE OSTI2024

Characterization of Fuel Cladding Chemical Interaction on a High Burnup U-10Zr Metallic Fuel via Electron Energy Loss Spectroscopy Enhanced by Machine Learning

Fuel cladding chemical interaction (FCCI) is one of the main performance limiting factors for metallic nuclear fuels. The interaction destabilizes the martensitic microstructure and deteriorates mechanical properties of HT-9 cladding. The detection of low atomic number elements (Z<10) and overlapping of elemental peaks can be problematic in interpreting energy dispersive X-ray spectroscopy (EDS) data. Electron energy loss spectroscopy (EELS) provides precise elemental edge energy values and can detect elements with a low atomic number. This work utilizes EELS to study the distribution of lanthanides and light elements at the interaction region. The sample was prepared from the FCCI region of a U-10Zr (wt.%) solid fuel with HT-9 cladding, irradiated to a burnup of 13.2 at.%. Processing the EELS data included three major steps: 1) enhance the signal to noise ratio by denoising the spectrum with principal component analysis (PCA) method, removing background and performing deconvolution; 2) identify chemical elements with core energy loss edges; 3) confirm different phases using a popular machine learning method, K-means. This work presents qualitative assessment of lanthanides and light elements like carbon (C) and oxygen (O) enhanced by the application of machine learning algorithms. By comparing with EDS elemental maps, EELS provides higher resolution chemical maps, reveals the distribution of carbon at the interaction region supporting the formation of zirconium carbide, a rind-like microstructure feature that was proposed to mitigate the chemical interaction. Furthermore, the plasmon peak map was also found to indicate an energy shift associated with the formation of phases/compounds. K-means clustering method was used on the processed electron energy loss (EEL) spectrum to automatically reveal different phases. The resulting clustered maps from K-means clustering align well with elemental maps confirming certain phases, especially Fe-Ce and Zr-C, in the FCCI region.

EELS↗