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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 325 records · Page 18

New constraints on heavy neutral leptons from Super-Kamiokande data

Abstract Heavy neutral leptons are predicted in many extensions of the Standard Model with massive neutrinos. If kinematically accessible, they can be copiously produced from kaon and pion decays in atmospheric showers, and subsequently decay inside large neutrino detectors. We perform a search for these long-lived particles using Super-Kamiokande multi-GeV neutrino data and derive stringent limits on the mixing with electron, muon and tau neutrinos as a function of the long-lived particle mass. We also present the limits on the branching ratio versus lifetime plane, which are helpful in determining the constraints in non-minimal models where the heavy neutral leptons have new interactions with the Standard Model.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Search for flavour-changing neutral-current couplings between the top quark and the Higgs boson in multi-lepton final states in 13 TeV pp collisions with the ATLAS detector

A search is presented for flavour-changing neutral-current interactions involving the top quark, the Higgs boson and an up-type quark (q = u, c ) with the ATLAS detector at the Large Hadron Collider. The analysis considers leptonic decays of the top quark along with Higgs boson decays into two W bosons, two Z bosons or a τ + τ - pair. It focuses on final states containing either two leptons (electrons or muons) of the same charge or three leptons. The considered processes are $t\bar{t}$ and Ht production. For the $t\bar{t}$ production, one top quark decays via $t\rightarrow Hq$. The proton–proton collision data set analysed amounts to (140 fb -1 ) at $(\sqrt{s}={13}\,\hbox {TeV})$. No significant excess beyond Standard Model expectations is observed and upper limits are set on the $t\rightarrow Hq$ branching ratios at 95 % confidence level, amounting to observed (expected) limits of $\mathcal {B}(t\rightarrow Hu)<2.8\,(3.0) \times 10^{-4}$ and $\mathcal {B}(t\rightarrow Hc)<3.3\,(3.8) \times 10^{-4}$. Combining this search with other searches for tHq flavour-changing neutral-current interactions previously conducted by ATLAS, considering $H\rightarrow b\bar{b}$ and $H\rightarrow \gamma \gamma$ decays, as well as $H\rightarrow \tau ^{+}\tau ^{-}$ decays with one or two hadronically decaying τ-leptons, yields observed (expected) upper limits on the branching ratios of $\mathcal {B}(t\rightarrow Hu)<2.6\,(1.8) \times 10^{-4}$ and $\mathcal {B}(t\rightarrow Hc)<3.4\,(2.3) \times 10^{-4}$.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

A new class of antibodies that overcomes a steric barrier to cross-group neutralization of influenza viruses

Antibody titers that inhibit the influenza virus hemagglutinin (HA) from engaging its receptor are the accepted correlate of protection from infection. Many potent antibodies with broad, intra-subtype specificity bind HA at the receptor binding site (RBS). One barrier to broad H1-H3 cross-subtype neutralization is an insertion (133a) between positions 133 and 134 on the rim of the H1 HA RBS. We describe here a class of antibodies that overcomes this barrier. These genetically unrestricted antibodies are abundant in the human B cell memory compartment. Analysis of the affinities of selected members of this class for historical H1 and H3 isolates suggest that they were elicited by H3 exposure and broadened or diverted by later exposure(s) to H1 HA. RBS mutations in egg-adapted vaccine strains cause the new H1 specificity of these antibodies to depend on the egg adaptation. The results suggest that suitable immunogens might elicit 133a-independent, H1-H3 cross neutralization by RBS-directed antibodies.

60 APPLIED LIFE SCIENCES↗

Broadly neutralizing humanized SARS-CoV-2 antibody binds to a conserved epitope on Spike and provides antiviral protection through inhalation-based delivery in non-human primates

The COVID-19 pandemic represents a global challenge that has impacted and is expected to continue to impact the lives and health of people across the world for the foreseeable future. The rollout of vaccines has provided highly anticipated relief, but effective therapeutics are required to further reduce the risk and severity of infections. Monoclonal antibodies have been shown to be effective as therapeutics for SARS-CoV-2, but as new variants of concern (VoC) continue to emerge, their utility and use have waned due to limited or no efficacy against these variants. Furthermore, cumbersome systemic administration limits easy and broad access to such drugs. As well, concentrations of systemically administered antibodies in the mucosal epithelium, a primary site of initial infection, are dependent on neonatal Fc receptor mediated transport and require high drug concentrations. To reduce the viral load more effectively in the lung, we developed an inhalable formulation of a SARS-CoV-2 neutralizing antibody binding to a conserved epitope on the Spike protein, ensuring pan-neutralizing properties. Administration of this antibody via a vibrating mesh nebulization device retained antibody integrity and resulted in effective distribution of the antibody in the upper and lower respiratory tract of non-human primates (NHP). In comparison with intravenous administration, significantly higher antibody concentrations can be obtained in the lung, resulting in highly effective reduction in viral load post SARS-CoV-2 challenge. This approach may reduce the barriers of access and uptake of antibody therapeutics in real-world clinical settings and provide a more effective blueprint for targeting existing and potentially emerging respiratory tract viruses.

60 APPLIED LIFE SCIENCES↗

LLNL - WRF-LES - Neutral - TTU

This dataset includes large-eddy simulation (LES) output from a neutrally stratified atmospheric boundary layer (ABL) simulation of observations at the SWIFT tower near Lubbock, Texas on Aug. 17, 2012. The dataset was used to assess LES models for simulation of canonical neutral ABL. The dataset can be used for comparison with other LES and computational fluid dynamics model outputs.

17 WIND ENERGY↗

ANL - WRF-LES - Neutral - TTU

This dataset includes large-eddy simulation (LES) output from a neutrally stratified atmospheric boundary layer (ABL) simulation of observations at the SWIFT tower near Lubbock, Texas on Aug. 17, 2012. The dataset was used to assess LES models for simulation of canonical neutral ABL. The dataset can be used for comparison with other LES and computational fluid dynamics model outputs.

17 WIND ENERGY↗

LANL - WRF-LES - Neutral - TTU

This dataset includes large-eddy simulation (LES) output from a neutrally stratified atmospheric boundary layer (ABL) simulation of observations at the SWIFT tower near Lubbock, Texas on Aug. 17, 2012. The dataset was used to assess LES models for simulation of canonical neutral ABL. The dataset can be used for comparison with other LES and computational fluid dynamics model outputs.

17 WIND ENERGY↗

NREL - SOWFA - Neutral - TTU

This dataset includes large-eddy simulation (LES) output from a neutrally stratified atmospheric boundary layer (ABL) simulation of observations at the SWIFT tower near Lubbock, Texas on Aug. 17, 2012. The dataset was used to assess LES models for simulation of canonical neutral ABL. The dataset can be used for comparison with other LES and computational fluid dynamics model outputs.

17 WIND ENERGY↗

LANL - Neutral - TTU

This dataset includes large-eddy simulation (LES) output from a neutrally stratified atmospheric boundary layer (ABL) simulation of observations at the SWIFT tower near Lubbock, Texas on Aug. 17, 2012. The dataset was used to assess LES models for simulation of canonical neutral ABL. The dataset can be used for comparison with other LES and computational fluid dynamics model outputs.

17 WIND ENERGY↗

Getting to Neutral: Options for Negative Carbon Emissions in California

This report is an assessment of negative emissions pathways - ones that physically remove CO 2 from the atmosphere - that can help California achieve carbon neutrality by 2045, or sooner. It integrates original research findings with current published research on three main pillars of negative emissions: natural and working lands, carbon capture from biomass conversion to fuels, and direct air capture. The focus and scope of this report is unique: it only addresses practices and technologies for removing carbon dioxide from the air. It also encompasses the entire breadth of strategies, from land management to the latest technological options, and it evaluates the cost of every step of the solution, from waste biomass collection to carbon dioxide transport and geologic storage. The methods are intended to be transparent; details of the calculations and underlying data are included in the report body and appendices. This study intentionally avoids any discussion of policies and does not include current incentives; it provides a range of options, tradeoffs and costs that can be used to inform future policies. The key finding of this report is that carbon neutrality is achievable.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Phosgene Neutralization Chemistry for the Explosive Destruction System (EDS)

This report summarizes activities at Sandia National Laboratories as part of the Explosive Destruction System (EDS) Phase 3 (P3) System design. An exploration of chemical neutralization strategies of phosgene was conducted for safe disposal of recovered mortars and M79 1000 lb. bombs filled with carbonyl dichloride "phosgene" or "CG agent" (molecular formula = COCl 2 ). The incumbent strategy utilized aqueous sodium hydroxide was found to be the worst-case scenario, producing enough CO 2 gas that would cause an unacceptable pressure and temperature spike. Several chemical neutralization strategies were evaluated based on criteria set by the operating envelope of the P3 design. In the end, it was determined that a pure solution of N-methyl ethanolamine (MeEA) or 90% monoethanolamine (MEA)(aqueous) provided the best balance reaction profile, cost, and safety.

36 MATERIALS SCIENCE↗

Basic Energy Sciences Roundtable: Foundational Science for Carbon-Neutral Hydrogen Technologies

The amount of molecular hydrogen used worldwide is enormous; about 70 million metric tons are produced globally every year, with approximately 10 million metric tons produced within the U.S. alone. 1 Hydrogen is used primarily by the industrial sector for oil refining; chemical production, especially for ammonia; steel manufacturing; and transportation fuels. With the recent announcement of the Hydrogen Shot, the first U.S. Department of Energy (DOE) Energy Earthshot, the DOE declared a near-term focus on “accelerating breakthroughs of more abundant, affordable, and reliable clean energy solutions within the decade.” Consequently, there is a compelling need for novel approaches to enable hydrogen processes and technologies that do not emit carbon dioxide (i.e., are carbon-neutral). Innovative hydrogen research and development is required to impact how hydrogen is produced, stored, transported, converted, and used. Although progress has been made over the previous two decades, fundamental research can play a critical role in overcoming the technical hurdles that continue to limit implementation of economically viable systems and processes for carbon-neutral hydrogen technologies.

08 HYDROGEN↗

What is Water's Role in a Carbon Neutral Future? A Summary of Findings from a Webinar Series

There has been ever-growing interest and engagement regarding net-zero and carbon neutrality goals, with many nations committing to steep emissions reductions by mid-century. Although water plays critical roles in various sectors, there has been a distinct gap in discussions to date about the role of water in the transition to a carbon neutral future. To address this need, a webinar was convened in April 2022 to gain insights into how water can support or influence active strategies for addressing emissions activities across energy, industrial, and carbon sectors. The webinar presentations and discussions highlighted various nuances of direct and indirect water use both within and across technology sectors (Figure ES-1). For example, hydrogen and concrete production, water for mining, and inland waterways transportation are all heavily influenced by the energy sources used (fossil fuels vs. renewable sources) as well as local resource availabilities. Algal biomass, on the other hand, can be produced across diverse geographies (terrestrial to sea) in a range of source water qualities, including wastewater and could also support pollution remediation through nutrient and metals recovery. Finally, water also influences carbon dynamics and cycling within natural systems across terrestrial, aquatic, and geologic systems. These dynamics underscore not only the critical role of water within the energy-water nexus, but also the extension into the energy-watercarbon nexus.

54 ENVIRONMENTAL SCIENCES↗

An Electron-Beam Ion-Neutralization Diagnostic for the Scorpius Radiography Accelerator

Electron beam spilling onto the beam pipe can produce positive ions that are accelerated inward into the beam body by its space charge. These ions partially neutralize the space charge, thereby causing the beam to be mismatched to the magnetic fields used for transport. A diagnostic of neutralization effects has been used on present accelerators, and in this note the feasibility of its use on a future accelerator is assessed.

43 PARTICLE ACCELERATORS↗

Measurement of Differential Neutral Current Elastic $ν_μ$-Argon Scattering Cross Sections with MicroBooNE

The MicroBooNE experiment is an 85 ton active mass liquid-argon time projection chamber located in the Fermilab Booster Neutrino Beamline. MicroBooNE’s ability to detect low-energy protons allows us to study single proton events with momenta as low as 300 MeV/c. We present a measurement of the flux-averaged neutral-current elastic differential cross section for neutrinos scattering on argon as functions of four-momentum transfer squared, Q 2 , proton kinetic energy, momentum and angle with respect to the beam direction. Our measured cross section as a function of Q 2 goes as low Q 2 = 0.10 GeV2 . This is our first step towards extracting the strange quark contribution to the axial form factor, which is not only the least-constrained contribution to the neutral-current elastic scattering cross section but is also crucial for understanding the strange quark contribution to the proton spin.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of Neutral-Current $\pi^0$ Cross Section in MicroBooNE using Wire-Cell Reconstruction

This note presents the extraction of flux-averaged total and differential neutral-current $π^0$ cross section measurements, based on the Wiener-SVD unfolding method, using the MicroBooNE Liquid Argon Time Projection Chamber (LArTPC) and the Wire-Cell reconstruction paradigm. This measurement is critical for single-photon searches as neutral-current pion production represents one of the largest sources of background. We report the results for an exposure corresponding to 5.327 × 10 19 protons-on-target (POT).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Progress Towards A Measurement of Neutrino Induced Charged Current Neutral Pion Production in the MicroBooNE Experiment

An analysis of MicroBooNE data with a signal of one muon, one neutral pion, and no charged pions is presented. Studying neutral pion production in the MicroBooNE detector provides an opportunity to better understand neutrino-argon interactions, and is crucial for future accelerator-based neutrino oscillation experiments. This analysis presents the progress towards the first measurement of the differential cross section for charged current (CC) $π^0$ production in neutrino-argon interactions. Using a dataset corresponding to about 7 × 10 20 protons on target (POT), we present an analysis which aims to measure the single differential cross sections as a function of the $π^0$ kinematic variables such as momentum and scattering angle. The Wiener-SVD technique for unfolding the measurement is presented and demonstrated using multiple generator predictions. A future iteration of this analysis will compare an unfolded data measurement to these models.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Neutrally-buoyant balloons experiment – EMRTC 2025

This memo announces the successful execution of the neutrally-buoyant balloon experiment (EMRTC 2025), conducted at New Mexico Institute of Mining and Technology’s Energetic Materials Research and Testing Center (EMRTC) in Socorro, NM between April 3 and May 9, 2025. The experiment aimed to build on EMRTC 2022 balloon experiment through testing the effects of lateral and vertical displacement of release locations in a different terrain than EMRTC 2022. EMRTC 2025 employed dual GPS trackers on each balloon to provide both detailed near-source motion tracking in addition to the low-frequency long-distance trackers used in EMRTC 2022. A total of 156 neutrally-buoyant balloons were released over the week of May 5-9, which was approximately 2.5 times the number released in the EMRTC 2022 campaign. The dual tracking system will allow characterizing complex three-dimensional wind structures close to terrain features and diurnal wind patterns to validate wind and plume dispersion models for treaty verification.

99 GENERAL AND MISCELLANEOUS↗