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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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Godiva-IV Dosimetry Exercise 2022 (IER-538 CED4A Report)

This report presents the final results of IER 538, The International Nuclear Accident Dosimeter (NAD) Intercomparison Exercise with Godiva-IV. The purpose of the exercise, held in August of 2022, was to test participants’ NADs and dosimetry personnel to the dose estimation requirements established by ANSI/HPS-N13.3 Dosimetry for Criticality Accidents and DOE-STD-1098-2017, Radiological Control. Two prompt critical bursts of the Godiva critical assembly were used to simulate criticality accidents, and NADs from participating laboratories were placed at known locations around Godiva, mounted on either BOttle Manikin ABsorptions (BOMABs) phantoms (to simulate doses received by people) or plates (to simulate doses in free air). Similar exercises have been held in 2016 and 2018 using National Criticality Experiments Research Center’s (NCERC’s) Flattop and Godiva assemblies.

61 RADIATION PROTECTION AND DOSIMETRY↗

stovertillage2019-bc1040-060

As part of the Billion Ton resource assessment projections created in 2016 (see https://www.energy.gov/sites/prod/files/2016/12/f34/2016_billion_ton_rep...), this dataset was produced and titled a "base-case" scenario. This broader dataset provided an updated assessment of the potential economic availability of biomass resources from agricultural lands reported at the farmgate under conservative assumptions. Crop residues quantified in this dataset include corn stover, cereal (wheat, oats, and barley) straws, and sorghum stubble. We have isolated corn stover in this dataset. What is the purpose of the data set? Why were the data collected?* Per request for use in subsequent research, we have isolated corn stover in 2019 from the broader base-case projections and have provided tillage classification details from this projection. Tillage classification assumptions in this scenario allow a moderate deviation from a baseline situation (using historic CTIC data on tillage type used in counties for each crop). This dataset allowed moderate flexibility of farmers to put land into another tillage type (no till, conservation till, and reduced till) where a higher net present value was calculated.

Davis, Maggie R.↗

SPRUCE: Sphagnum Carbon, Nitrogen and Phosphorus Concentrations in the SPRUCE Experimental Plots

This data set reports the concentrations of carbon (C), nitrogen (N), and phosphorus (P) in capitula, current year stems, and one-year old stem tissue of Sphagnum from 2016-2018. Measurements are continuing and new data will be appended as they become available. Three types of Sphagnum were sampled -- S. angustifolium/fallax from hummocks (AngFal_Hum), S. angustifolium/fallax from hollows (AngFal_Hol), and S. magellanicum from hummocks (Mag_Hum) from SPRUCE experimental study plots. Measurements were made in 10 enclosures comprising five levels of temperature elevation in ambient CO2 and five levels in elevated CO2. Measurements also were made in two ambient (no enclosure) plots. Nutrient concentrations were analyzed in conjunction with assessment of Sphagnum growth, which was measured in 3.79-cm diameter mesh columns collected every October and are described in the related dataset (https://doi.org/10.25581/spruce.049/1426474). The SPRUCE experiment is being conducted at the 8.1-ha S1 bog forest site in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF).

54 ENVIRONMENTAL SCIENCES↗

Cryo-vacuum testing of the JWST Integrated Science Instrument Module (SPIE)

In late 2015/early 2016, a major cryo-vacuum test was carried out for the Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST). This test comprised the final cryo-certification and calibration test of the ISIM, after its ambient environmental test program (vibration, acoustics, EMI/EMC), and before its delivery for integration with the rest of the JWST observatory. Over the 108-day period of the round-the-clock test program, the full complement of ISIM flight instruments, structure, harness radiator, and electronics were put through a comprehensive program of thermal, optical, electrical, and operational tests. The test verified the health and excellent performance of the instruments and ISIM systems, proving the ISIM element's readiness for integration with the telescope. We report here on the context, goals, setup, execution, and key results for this critical JWST milestone.

James Webb Space Telescope (JWST)↗

Spatial and temporal trends and variabilities of hailstones in the United States Northern Great Plains and their possible attributions

Following on our study of hail for the Southern Great Plains (SGP), we investigated the spatial and temporal hail trends and variabilities for the Northern Great Plains (NGP) and the contributing factors for summer seasons (June–August) over 2004–2016 using two independent hail datasets. Both severe hail (1 < diameter = 2 inches) and significant severe hail (diameter > 2 inches) were examined and similar results were obtained. The hailstones in the NGP demonstrate a large interannual variability, with an overall increasing trend over 2004–2016. Spatially, the positive trend is mainly located in the western part of South Dakota and North Dakota. We find the three major dynamical factors that most likely contribute to the hail interannual variability in the NGP are the El Niño-Southern Oscillation (ENSO), North Atlantic subtropical high (NASH), and low-level jet (LLJ). With a thermodynamical variable integrated water vapor transport (IVT) that is strongly controlled by LLJ, the four factors can explain 76% of the hail interannual variability from the hail reports based on the multivariate linear regression. Hail occurrences are 73% higher during the cold phase of ENSO (La Nin~a) than the warm phase of ENSO (El Nin~o). When the NASH has a larger northwestward expansion or stronger intensity, more hail occurs over the NGP, because the increases of latitudinal gradient of pressure leads to a stronger LLJ. Interestingly, the important factors impacting hail interannual variability over the NGP are quite different from those for the SGP, except ENSO.

Jeong, Jong-Hoon↗

FAIR for AI: An interdisciplinary and international community building perspective

A foundational set of findable, accessible, interoperable, and reusable (FAIR) principles were proposed in 2016 as prerequisites for proper data management and stewardship, with the goal of enabling the reusability of scholarly data. The principles were also meant to apply to other digital assets, at a high level, and over time, the FAIR guiding principles have been re-interpreted or extended to include the software, tools, algorithms, and workflows that produce data. FAIR principles are now being adapted in the context of AI models and datasets. Here, we present the perspectives, vision, and experiences of researchers from different countries, disciplines, and backgrounds who are leading the definition and adoption of FAIR principles in their communities of practice, and discuss outcomes that may result from pursuing and incentivizing FAIR AI research. The material for this report builds on the FAIR for AI Workshop held at Argonne National Laboratory on June 7, 2022.

97 MATHEMATICS AND COMPUTING↗

Significant Tropospheric O3 Production from Extratropical Forest Fires:When? When Not?

There is significant controversy on whether extratropical fires contribute importantly to widespread ozone productionabsent the addition of urban pollutant nitrogen oxides (Jaffe and Widger, 2012, Singh et al., 2012,2013). Wereport a significant range of O3 production early in the fire plume history and report controls on which notable O3production occurs. The current data set is the airborne observations made on board NASAs highly instrumentedDC-8 aircraft during the ARCTAS (2008) and SEAC4RS (2013) campaigns within the Western United States. Aclear analysis of fire emissions was aided considerably by MERET (a Mixed Effects Regressions Emissions Technique).This technique allows consistent emission factors and enhancement ratios for O3 for individual aircraftsamples largely free from uncertainties resulting from mixing and entrainment which plague many published estimates.(Yokelson et al, 2013, Chatfield and Andreae, 2016). We find support for the reasonable idea that the ratioof nitrogen oxides (NOx) to volatile organic carbon (VOC) emissions controls new O3 production. The evidence isfor significant O3 production from high-fuel-nitrogen fuels (as evidenced by acetonitrile) and extremely hot largefires (like the Yosemite Rim Fire of 2013 which we analyze), while others do not. VOC emissions factors varysignificantly from fire to fire (and from different samples in the Rim Fire). Relative CO production (aka modifiedcombustion efficiency) is only one factor describing VOC emissions factors.

Chatfield, R.↗

Recalibration of the Sunspot-Number: Status Report

We report progress on the ongoing recalibration of the Wolf sunspot number (S N ) and group-sunspot number (G N ) following the release of version 2.0 of S N in 2015. This report constitutes both an update of the efforts reported in the 2016 Topical Issue of Solar Physics and a summary of work by the International Space Science Institute (ISSI) International Team formed in 2017 to develop optimal S N and G N reconstruction methods while continuing to expand the historical sunspot-number database. Significant progress has been made on the database side while more work is needed to bring the various proposed S N and (primarily) G N reconstruction methods closer to maturity, after which the new reconstructions (or combinations thereof) can be compared with (a) “benchmark” expectations for any normalization scheme (e.g., a general increase in observer normalization factors going back in time), and (b) independent proxy data series such as F10.7 and the daily range of variations of Earth’s undisturbed magnetic field. New versions of the underlying databases for S N and G N will shortly become available for years through 2022 and we anticipate the release of the next versions of these two time series in 2024.

F. Clette↗

The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope

We report the fourth catalog of active galactic nuclei (AGNs) detected by the Fermi Gamma-ray Space Telescope Large Area Telescope (4LAC) between 2008 August 4 and 2016 August 2 contains objects located at high Galactic latitudes ( ). It includes 85% more sources than the previous 3LAC catalog based on 4 yr of data. AGNs represent at least 79% of the high-latitude sources in the fourth Fermi -Large Area Telescope Source Catalog (4FGL), which covers the energy range from 50 MeV to 1 TeV. In addition, gamma-ray AGNs are found at low Galactic latitudes. Most of the 4LAC AGNs are blazars (98%), while the remainder are other types of AGNs. The blazar population consists of 24% Flat Spectrum Radio Quasars (FSRQs), 38% BL Lac-type objects, and 38% blazar candidates of unknown types (BCUs). On average, FSRQs display softer spectra and stronger variability in the gamma-ray band than BL Lacs do, confirming previous findings. All AGNs detected by ground-based atmospheric Cerenkov telescopes are also found in the 4LAC.

79 ASTRONOMY AND ASTROPHYSICS↗

Forbush Decreases and < 2 Day GCR Flux Non-recurrent Variations Studied with LISA Pathfinder

Non-recurrent short-term variations of the galactic cosmic-ray (GCR) flux above 70 MeV n−1 were observed between 2016 February 18 and 2017 July 3 on board the European Space Agency LISA Pathfinder (LPF) mission orbiting around the Lagrange point L1 at 1.5 × 106 km from Earth. The energy dependence of three Forbush decreases is studied and reported here. A comparison of these observations with others carried out in space down to the energy of a few tens of MeV n−1 shows that the same GCR flux parameterization applies to events of different intensity during the main phase. FD observations in L1 with LPF and geomagnetic storm occurrence are also presented. Finally, the characteristics of GCR flux non-recurrent variations (peaks and depressions) of duration <2 days and their association with interplanetary structures are investigated. It is found that, most likely, plasma compression regions between subsequent corotating high-speed streams cause peaks, while heliospheric current sheet crossing causes the majority of the depressions.

M. Armano↗

Forbush Decreases and <2 Day GCR Flux Non-Recurrent Variations Studied with LISA Pathfinder

Non-recurrent short-term variations of the galactic cosmic-ray (GCR) flux above 70 MeV n(exp −1) were observed between 2016 February 18 and 2017 July 3 on board the European Space Agency LISA Pathfinder (LPF) mission orbiting around the Lagrange point L1 at 1.5 × 10 (exp 6) km from Earth. The energy dependence of three Forbush decreases is studied and reported here. A comparison of these observations with others carried out in space down to the energy of a few tens of MeV n(exp −1) shows that the same GCR flux parameterization applies to events of different intensity during the main phase. FD observations in L1 with LPF and geomagnetic storm occurrence are also presented. Finally, the characteristics of GCR flux non-recurrent variations (peaks and depressions) of duration <2 days and their association with interplanetary structures are investigated. It is found that, most likely, plasma compression regions between subsequent corotating high-speed streams cause peaks, while heliospheric current sheet crossing causes the majority of the depressions.

Cosmic rays↗

Greased Lightning (GL-10) Performance Flight Research: Flight Data Report

Modern aircraft design methods have produced acceptable designs for large conventional aircraft performance. With revolutionary electronic propulsion technologies fueled by the growth in the small UAS (Unmanned Aerial Systems) industry, these same prediction models are being applied to new smaller, and experimental design concepts requiring a VTOL (Vertical Take Off and Landing) capability for ODM (On Demand Mobility). A 50% sub-scale GL-10 flight model was built and tested to demonstrate the transition from hover to forward flight utilizing DEP (Distributed Electric Propulsion)[1][2]. In 2016 plans were put in place to conduct performance flight testing on the 50% sub-scale GL-10 flight model to support a NASA project called DELIVER (Design Environment for Novel Vertical Lift Vehicles). DELIVER was investigating the feasibility of including smaller and more experimental aircraft configurations into a NASA design tool called NDARC (NASA Design and Analysis of Rotorcraft)[3]. This report covers the performance flight data collected during flight testing of the GL-10 50% sub-scale flight model conducted at Beaver Dam Airpark, VA. Overall the flight test data provides great insight into how well our existing conceptual design tools predict the performance of small scale experimental DEP concepts. Low fidelity conceptual design tools estimated the (L/D)( sub max)of the GL-10 50% sub-scale flight model to be 16. Experimentally measured (L/D)( sub max) for the GL-10 50% scale flight model was 7.2. The aerodynamic performance predicted versus measured highlights the complexity of wing and nacelle interactions which is not currently accounted for in existing low fidelity tools.

McSwain, Robert G.↗

Energy dependence of chain fission product yields from neutron-induced fission of 235 U, 238 U, and 239 Pu

The lack of completeness and systematic studies of cumulative fission product yield (FPY) from the three major actinides of 235 U, 238 U, and 239 Pu, over a broad energy range, was the primary motivation for the LLNL-LANL-TUNL collaboration. Given the focus on resolving FPY behavior around fission spectrum neutron energies, our 2016 data provides FPY measurements in fine energy steps in the range of 0.5–5.5 MeV and an additional anchor point at 14.8 MeV. Recently, our collaboration filled the gap between second chance fission and 14.8 MeV, providing a comprehensive study at eleven incident neutron energies from 0.5 to 14.8 MeV. However, during the course of the last measurements, it was found that the reported masses of the actinide deposits in the fission ionization chambers, which were used to measure the number of fissions, were not consistent with the complementary tests. Therefore, some corrections to the old data are needed. The purpose of this paper is to summarize all of the high-yield FPY data obtained for 235 U, 238 U, and 239 Pu isotopes using quasi-monoenergetic neutron beams at 11 incident energies ranging from E n = 0.5 to 14.8 MeV.

Tonchev, A. P. [Lawrence Livermore National Labora↗

Characterization of the quantum state of top quark pairs produced in proton-proton collisions at $\sqrt{s}$ = 13 TeV using the beam and helicity bases

Measurements of the spin correlation coefficients in the beam basis are presented for top quark-antiquark $(t\bar{t}⁢)$ systems produced in proton-proton collisions at $\sqrt{s}$ = 13 TeV collected by the CMS experiment in 2016–2018, and corresponding to an integrated luminosity of 138 fb −1 . The $t\bar{t}$ system is reconstructed from final states containing an electron or muon and jets. Together with the previously reported results in the helicity basis, these measurements are used to decompose the system into the Bell and spin eigenstates in various kinematic regions. The spin correlation coefficients are also used to evaluate properties of the $t\bar{t}$ quantum state, such as the purity, von Neumann entropy, and entanglement. All results are consistent with standard model predictions.

Hayrapetyan, Aram [Yerevan Physics Institute]↗

Residential Solar-Adopter Income and Demographic Trends: November 2022 Update [Slides]

The report describes income, demographic, and other socio-economic trends among U.S. residential rooftop solar adopters. The report is based on address-level data for roughly 2.8 million residential rooftop solar systems installed through 2021, representing 86% of all U.S. systems. With its unique size, geographic scope, and level of detail, this report is intended to serve as a foundational reference document for policy-makers, industry stakeholders, and researchers. Key findings include the following: -Median solar adopter income was about $\$110$k/year in 2021, compared to a U.S. median of about $\$63$k/year for all households and $\$79$k/year for all owner-occupied households -The degree of income skew varies significantly across all states, but all states exhibit some positive income skew, with median solar-adopter incomes ranging from 131-168% of the respective county-median income for all households -Notwithstanding the fact that solar adopter incomes skew high, a substantial share of adopters could be considered low-to-moderate income (LMI), with 22% of all 2021 adopters earning less than 80% of area median income, and an additional 21% between 80% and 120% of area median income. -Solar-adopter incomes are declining over time, with median incomes dropping from $\$129$k in 2010 to $\$110$k in 2021, as adoption becomes more proportionately distributed across the population and has started to broaden into low- and middle-income states since 2016. -Solar-adopter incomes are consistently higher for systems paired with battery storage, for host-owned systems, and for systems installed on single-family homes; higher income adopters also consistently install larger systems. -Solar adopters tend to live in Census Tracts not identified as “disadvantaged communities” (using the U.S. Department of Energy’s interim definitions developed March 2022), making up 11% of adopters compared to 18% of U.S. households. -Compared to the broader population, solar adopters tend to: identify as Non-Hispanic White, be primarily English-speaking, have higher education levels, be middle-aged, work in business and finance-related occupations, and live in higher-value homes In conjunction with the report, Berkeley Lab has published an updated accompanying set of online data visualizations that allow users to further explore the underlying data. Berkeley Lab is also offering related analytical support to states, local agencies, and other organizations on issues related to solar adoption among low-to-moderate income households; requests for analytical support may be submitted through this online form.

13 HYDRO ENERGY↗

Measurements of Higgs boson production cross sections and couplings in the diphoton decay channel at $ \sqrt{\mathrm{s}} $ = 13 TeV

Measurements of Higgs boson production cross sections and couplings in events where the Higgs boson decays into a pair of photons are reported. Events are selected from a sample of proton-proton collisions at s√ = 13 TeV collected by the CMS detector at the LHC from 2016 to 2018, corresponding to an integrated luminosity of 137 fb -1 . Analysis categories enriched in Higgs boson events produced via gluon fusion, vector boson fusion, vector boson associated production, and production associated with top quarks are constructed. The total Higgs boson signal strength, relative to the standard model (SM) prediction, is measured to be 1.12±0.09. Other properties of the Higgs boson are measured, including SM signal strength modifiers, production cross sections, and its couplings to other particles. These include the most precise measurements of gluon fusion and vector boson fusion Higgs boson production in several different kinematic regions, the first measurement of Higgs boson production in association with a top quark pair in five regions of the Higgs boson transverse momentum, and an upper limit on the rate of Higgs boson production in association with a single top quark. All results are found to be in agreement with the SM expectations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Determination of the spin and parity of all-charm tetraquarks

The traditional quark model accounts for the existence of baryons, such as protons and neutrons, which consist of three quarks, as well as mesons, composed of a quark–antiquark pair. Only recently has substantial evidence started to accumulate for exotic states composed of four or five quarks and antiquarks. The exact nature of their internal structure remains uncertain. Here we report the first measurement of quantum numbers of the recently discovered family of three all-charm tetraquarks, using data collected by the CMS experiment at the Large Hadron Collider from 2016 to 2018 . The angular analysis techniques developed for the discovery and characterization of the Higgs boson have been applied to the new exotic states. Here we show that the quantum numbers for parity P and charge conjugation C symmetries are found to be +1. The spin J of these exotic states is determined to be consistent with 2ħ, while 0ħ and 1ħ are excluded at 95% and 99% confidence levels, respectively. The J PC = 2 ++ assignment implies particular configurations of constituent spins and orbital angular momenta, which constrain the possible internal structure of these tetraquarks.

Physics↗

Atmospheric Carbon and Transport – America (ACT-America) Data Sets: Description, Management, and Delivery

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. In this study, we conducted 121 research flights during five campaigns in four seasons during 2016–2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

54 ENVIRONMENTAL SCIENCES↗