Search NASA⌕ Search

SEARCH · Search NASA

Results for “EXCLUSIVE INTERACTIONS”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Exclusive π - electroproduction off the neutron in deuterium in the resonance region

We report new results for the exclusive and quasi-free cross sections off neutrons bound in deuterium y v n(p) →p π - (p) are presented over a wide final state hadron angle range with a kinematic coverage of the invariant mass (W) up to 1.825 GeV and the virtual photon four-momentum transfer squared (Q 2 ) from 0.4 to 1.0 GeV 2 . The exclusive structure functions have been extracted and their Legendre moments were obtained. Final-state-interaction contributions have been kinematically separated from the extracted quasi-free cross sections off bound neutrons solely based on the analysis of the experimental data. These new results will serve as long-awaited input for phenomenological analyses to extract the Q 2 evolution of previously unavailable n → N* electroexcitation amplitudes and to improve state-of-the-art models of neutrino scattering off nuclei by augmenting the already available results from free protons.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2019

Hadronic tau decays as new physics probes in the LHC era

We analyze the sensitivity of hadronic τ decays to nonstandard interactions within the model-independent framework of the standard model effective field theory. Both exclusive and inclusive decays are studied, using the latest lattice data and QCD dispersion relations. We show that there are enough theoretically clean channels to disentangle all the effective couplings contributing to these decays, with the τ → ππν τ channel representing an unexpected powerful new physics probe. We find that the ratios of nonstandard couplings to the Fermi constant are bound at the subpercent level. These bounds are complementary to the ones from electroweak precision observables and pp → τν τ measurements at the LHC. The combination of τ decay and LHC data puts tighter constraints on lepton universality violation in the gauge boson-lepton vertex corrections.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2024

Transcriptomics reveal a mechanism of niche defense: two beneficial root endophytes deploy an antimicrobial GH18-CBM5 chitinase to protect their hosts

Effector secretion is crucial for root endophytes to establish and protect their ecological niche. We used time-resolved transcriptomics to monitor effector gene expression dynamics in two closely related Sebacinales, Serendipita indica and Serendipita vermifera, during symbiosis with three plant species, competition with the phytopathogenic fungus Bipolaris sorokiniana, and cooperation with root-associated bacteria. We observed increased effector gene expression in response to biotic interactions, particularly with plants, indicating their importance in host colonization. Some effectors responded to both plants and microbes, suggesting dual roles in intermicrobial competition and plant–microbe interactions. A subset of putative antimicrobial effectors, including a GH18-CBM5 chitinase, was induced exclusively by microbes. Functional analyses of this chitinase revealed its antimicrobial and plant-protective properties. We conclude that dynamic effector gene expression underpins the ability of Sebacinales to thrive in diverse ecological niches with a single fungal chitinase contributing substantially to niche defense.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2026

First results from the search of $ν_μ$ disappearance with ICARUS

his work presents a search for muon neutrino disappearance signal using the ICARUS detector. ICARUS is currently working as the far detector of the Short-Baseline Neutrino (SBN) program. Its main goal is to investigate the possible oscillation of a sterile neutrino state ($\Delta m^2 \sim \text{eV}^2$), that would drive short baseline oscillations at the scale of L/E $\sim$ km/GeV. Neutrino interactions from the Booster Neutrino Beam (BNB) are investigated, looking for simple final state topology with a single muon and at least one proton (1$\mu$Np). This analysis tests the 3+1 model using the two flavor neutrino approximation, where careful consideration has been given to the systematic uncertainties arising from flux, neutrino interaction, and detector models. No statistically significant $\nu_\mu$ disappearance is observed, hence 90\% C.L. exclusion contours are reported in the $\Delta m^2_{41} - \sin^22\theta_{\mu\mu}$ parameter space.

Artero Pons, Maria [INFN, Padua; U. Padua (main)]↗
DOE OSTI2023

Community response of soil microorganisms to combined contamination of polycyclic aromatic hydrocarbons and potentially toxic elements in a typical coking plant

Both polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) of coking industries impose negative effects on the stability of soil ecosystem. Soil microbes are regarded as an essential moderator of biochemical processes and soil remediation, while their responses to PAHs-PTEs combined contamination are largely unknown. In the present study, soil microbial diversity and community composition in the typical coking plant under the chronic co-exposure of PAHs and PTEs were investigated and microbial interaction networks were built to reveal microbial co-occurrence patterns. The results indicated that the concentrations of PAHs in the soil inside the coking plant were significantly higher than those outside the plant. The mean concentration of ∑16PAHs was 2894.4 ng·g −1 , which is 5.58 times higher than that outside the plant. The average Hg concentration inside the coking plant was 22 times higher than the background value of Hebei province. The soil fungal community inside the coking plant showed lower richness compared with that of outside community, and there are significant difference in the bacterial and fungal community composition between inside and outside of coking plant ( p < 0.01). Predicted contribution of different environmental factors to each dominant species based on random forest identified 20 and 25 biomarkers in bacteria and fungi, respectively, that were highly sensitive to coking plant soil in operation, such as Betaproteobacteria，Sordariomycetes and Dothideomycetes . Bacterial and fungal communities were shaped by the soil chemical properties (pH), PTEs (Hg), and PAHs together in the coking plant soils. Furthermore, the bacterial and fungal interaction patterns were investigated separately or jointly by intradomain and interdomain networks. Competition is the main strategy based on the co-exclusion pattern in fungal community, and the competitive relationship inside the coking plant is more complex than that outside the plant. In contrast, cooperation is the dominant strategy in bacterial networks based on the co-occurrence pattern. The present study provided insights into microbial response strategies and the interactions between bacteria and fungi under long-term combined contamination.

Shen, Qihui↗
DOE OSTI2024

First Constraints on WIMP-Nucleon Effective Field Theory Couplings in an Extended Energy Region From LUX-ZEPLIN

Following the first science results of the LUX-ZEPLIN (LZ) experiment, a dual-phase xenon time projection chamber operating from the Sanford Underground Research Facility in Lead, South Dakota, USA, we report the initial limits on a model-independent non-relativistic effective field theory describing the complete set of possible interactions of a weakly interacting massive particle (WIMP) with a nucleon. These results utilize the same 5.5 t fiducial mass and 60 live days of exposure collected for the LZ spin-independent and spin-dependent analyses while extending the upper limit of the energy region of interest by a factor of 7.5 to 270~keV. No significant excess in this high energy region is observed. Using a profile-likelihood ratio analysis, we report 90% confidence level exclusion limits on the coupling of each individual non-relativistic WIMP-nucleon operators for both elastic and inelastic interactions in the isoscalar and isovector bases.

Source record↗
DOE OSTI2023

Design of enhanced porous organic cage solubility in Type 2 porous liquids

Decreasing cost of technologies for direct air capture of carbon can be achieved through the design of new materials with high CO 2 selectivity that can be incorporated into existing industrial processes. An emerging class of materials for these applications are porous liquids (PLs). PLs are mixtures of porous hosts and solvents with intrinsic porosity due to steric exclusion of solvent from inside the porous host. It is currently unknown how solvent -porous host interactions affect porous host solubility in the bulk solvent. Here, in this study, density functional theory simulations were used to investigate interactions between nine solvents and a CC13 porous organic cage (POC). Calculations identified that solvent molecules were the most stable when placed either inside the CC13 POC or in the pore window compared to interfacial binding sites. Structural changes to the CC13 POC correlated with reported experimental solubilities, including expansion of the CC13 POC with solvent molecule infiltration and expansion or contraction of the pore window. Based on these results, new PL design guidelines should include compositions with (1) high concentrations of POCs with flexible cage structures that can expand when solvated and (2) solvent molecule-POC combinations that contract the pore window during solvent molecule-host binding.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Full- f version of GENE for turbulence in open-field-line systems

Exclusive properties of plasmas in the tokamak edge, such as large amplitude fluctuations and plasma–wall interactions in the open-field-line regions, require major modifications of existing gyrokinetic codes originally designed for simulating core turbulence. Thus, the global version of the 3D2V gyrokinetic code GENE, so far employing a δf-splitting technique, is extended to simulate electrostatic turbulence in straight open-field-line systems. The significant extensions are the inclusion of the velocity-space nonlinearity, the development of a conducting-sheath boundary, and the implementation of the Lenard–Bernstein collision operator. With these developments, the code can be run as a full-f code and can handle particle loss to and reflection from the wall. The extended code is applied to modeling turbulence in the Large Plasma Device (LAPD), with a reduced mass ratio and a much lower collisionality. Similar to turbulence in a tokamak scrape-off layer, LAPD turbulence involves collisions, parallel streaming, cross-field turbulent transport with steep profiles, and particle loss at the parallel boundary.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2019

Boundary conditions and Berry phase in magnetic nanostructures

The effect of micromagnetic boundary conditions on the Berry curvature and topological Hall effect in granular nanostructures is investigated by model calculations. Both free surfaces and grain boundaries between interacting particles or grains affect the spin structure. The Dzyaloshinskii-Moriya interactions yield corrections to the Erdmann-Weierstrass boundary conditions, but the Berry curvature remains an exclusive functional of the local spin structure, which greatly simplifies the treatment of nanostructures. An explicit example is a model nanostructure with cylindrical symmetry whose spin structure is described by Bessel function and which yields a mean-field-type Hall-effect contribution that can be related to magnetic-force-microscopy images.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Searching for MeV-mass neutrinophilic dark matter with large scale dark matter detectors

The indirect detection of dark matter (DM) through its annihilation products is one of the primary strategies for DM detection. One of the least constrained classes of models is neutrinophilic DM, because the annihilation products, weakly interacting neutrinos, are challenging to observe. Here, we consider a scenario where MeV-mass DM exclusively annihilates to the third neutrino mass eigenstate, which is predominantly of tau and muon flavor. In such a scenario, the potential detection rate of the neutrinos originating from the DM annihilation in our Galaxy in the conventional detectors would be suppressed by up to approximately two orders of magnitude. This is because the best sensitivity of such detectors for neutrinos with energies below approximately 100 MeV is for electron neutrino flavor. In this work, we highlight the potential of large-scale DM detectors in uncovering such signals in the tens of MeV range of DM masses. In addition, we discuss how coincident signals in direct detection DM experiments and upcoming neutrino detectors such as DUNE, Hyper-Kamiokande, and JUNO could provide new perspectives on the DM problem. Published by the American Physical Society 2025

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2015

Metabolic functions of Pseudomonas fluorescens strains from Populus deltoides depend on rhizosphere or endosphere isolation compartment

The bacterial microbiota of plants is diverse, with ~1000s of operational taxonomic units (OTUs) associated with any individual plant. In this work we investigate how 19 sequenced Pseudomonas fluorescens strains representing a single OTU isolated from Populus deltoides rhizosphere and endosphere differ using phenotypic analysis, comparative genomics, and metabolic models. While no traits were exclusive to either endosphere or rhizosphere P. fluorescens isolates, multiple pathways relevant for bacterial-plant interactions are enriched in endosphere isolate genomes and growth phenotypes such as phosphate solubilization, protease activity, denitrification and root growth promotion are biased towards endosphere isolates. Endosphere isolates have more metabolic pathways for plant signaling compounds and an increased metabolic range that includes utilization of energy rich nucleotides and sugars, consistent with endosphere colonization. Rhizosphere P. fluorescens have fewer pathways important for bacterial-plant interactions but show metabolic bias towards chemical substrates often found in root exudates. This work reveals the diverse functions that may contribute to colonization of the endosphere by bacteria that are enriched in event he most closely related isolates.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2017

Structure-based nuclear import mechanism of histones H3 and H4 mediated by Kap123

Kap123, a major karyopherin protein of budding yeast, recognizes the nuclear localization signals (NLSs) of cytoplasmic histones H3 and H4 and translocates them into the nucleus during DNA replication. Mechanistic questions include H3- and H4-NLS redundancy toward Kap123 and the role of the conserved diacetylation of cytoplasmic H4 (K5ac and K12ac) in Kap123-mediated histone nuclear translocation. Here, we report crystal structures of full-length Kluyveromyces lactis Kap123 alone and in complex with H3- and H4-NLSs. Structures reveal the unique feature of Kap123 that possesses two discrete lysine-binding pockets for NLS recognition. Structural comparison illustrates that H3- and H4-NLSs share at least one of two lysine-binding pockets, suggesting that H3- and H4-NLSs are mutually exclusive. Additionally, acetylation of key lysine residues at NLS, particularly H4-NLS diacetylation, weakens the interaction with Kap123. These data support that cytoplasmic histone H4 diacetylation weakens the Kap123-H4-NLS interaction thereby facilitating histone Kap123-H3-dependent H3:H4/Asf1 complex nuclear translocation.

An, Sojin↗
NASA NTRS2014

Vibrational Frequencies and Spectroscopic Constants for 1(sup 3)A' HNC and 1(sup 3)A' HOC+ from High-Accuracy Quartic Force Fields

The spectroscopic constants and vibrational frequencies for the 1(sup 3)A' states of HNC, DNC, HOC+, and DOC+ are computed and discussed in this work. The reliable CcCR quartic force field based on high-level coupled cluster ab initio quantum chemical computations is exclusively utilized to provide the anharmonic potential. Then, second order vibrational perturbation theory and vibrational configuration interaction methods are employed to treat the nuclear Schroedinger equation. Second-order perturbation theory is also employed to provide spectroscopic data for all molecules examined. The relationship between these molecules and the corresponding 1(sup 3)A' HCN and HCO+ isomers is further developed here. These data are applicable to laboratory studies involving formation of HNC and HOC+ as well as astronomical observations of chemically active astrophysical environments.

Astrochemistry↗
DOE OSTI2026

First search for sterile neutrino oscillation leading to $ν_μ$ disappearance in the Booster Neutrino Beam at ICARUS

We present a search for muon neutrino disappearance in the Booster Neutrino Beam (BNB) at Fermilab using the ICARUS detector. Neutrino interactions identified as muon neutrinos interacting with argon nuclei via the charged current interaction and having only a muon and at least one proton in the final state (1$μ$Np) have been selected from data collected in 2022-2023 (ICARUS Run 2) and compared with a simulation-based expectation. In the context of a fit to a two-neutrino approximation of the sterile 3+1 model, including the impact of systematic uncertainty from the flux, neutrino interaction, and detector models, we find no statistically significant muon neutrino disappearance at the ICARUS baseline of 600 meters from the BNB target. Corresponding 90% C.L. exclusion contours in $Δm^2_{41}$ - sin$^22θ_{μμ}$ space are presented. This is the first oscillation analysis produced by ICARUS exposed to the BNB. We note that the analysis is systematics limited due to large unconstrained uncertainties from the flux and interaction models. In future joint analyses, data from ICARUS and the SBND detector, exposed to the BNB at 110 meters from target, will be combined to provide significant constraint of these uncertainties, enabling a robust, world-leading two-detector analysis.

Alrahman, F. Abd [Houston U.]↗
DOE OSTI2023

Throughfall exclusion and fertilization effects on tropical dry forest tree plantations, a large-scale experiment

Abstract. Across tropical ecosystems, global environmental change is causing drier climatic conditions and increased nutrient deposition. Such changes represent large uncertainties due to unknown interactions between drought and nutrient availability in controlling ecosystem net primary productivity (NPP). Using a large-scale manipulative experiment, we studied for 4 years whether nutrient availability affects the individual and integrated responses of aboveground and belowground ecosystem processes to throughfall exclusion in 30-year-old mixed plantations of tropical dry forest tree species in Guanacaste, Costa Rica. We used a factorial design with four treatments: control, fertilization (F), drought (D), and drought + fertilization (D + F). While we found that a 13 %–15 % reduction in soil moisture only led to weak effects in the studied ecosystem processes, NPP increased as a function of F and D + F. The relative contribution of each biomass flux to NPP varied depending on the treatment, with woody biomass being more important for F and root biomass for D + F and D. Moreover, the F treatment showed modest increases in maximum canopy cover. Plant functional type (i.e., N fixation or deciduousness) and not the experimental manipulations was the main source of variation in tree growth. Belowground processes also responded to experimental treatments, as we found a decrease in nodulation for F plots and an increase in microbial carbon use efficiency for F and D plots. Our results emphasize that nutrient availability, more so than modest reductions in soil moisture, limits ecosystem processes in tropical dry forests and that soil fertility interactions with other aspects of drought intensity (e.g., vapor pressure deficit) are yet to be explored.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Nucleon Resonance Electroexcitation Amplitudes and Emergent Hadron Mass

Understanding the strong interaction dynamics that govern the emergence of hadron mass (EHM) represents a challenging open problem in the Standard Model. In this paper we describe new opportunities for gaining insight into EHM from results on nucleon resonance (N*) electroexcitation amplitudes (i.e., γvpN* electrocouplings) in the mass range up to 1.8 GeV for virtual photon four-momentum squared (i.e., photon virtualities Q2) up to 7.5 GeV2 available from exclusive meson electroproduction data acquired during the 6-GeV era of experiments at Jefferson Laboratory (JLab). These results, combined with achievements in the use of continuum Schwinger function methods (CSMs), offer new opportunities for charting the momentum dependence of the dressed quark mass from results on the Q2-evolution of the γvpN* electrocouplings. This mass function is one of the three pillars of EHM and its behavior expresses influences of the other two, viz. the running gluon mass and momentum-dependent effective charge. A successful description of the Δ(1232)3/2+ and N(1440)1/2+ electrocouplings has been achieved using CSMs with, in both cases, common momentum-dependent mass functions for the dressed quarks, for the gluons, and the same momentum-dependent strong coupling. The properties of these functions have been inferred from nonperturbative studies of QCD and confirmed, e.g., in the description of nucleon and pion elastic electromagnetic form factors. Parameter-free CSM predictions for the electrocouplings of the Δ(1600)3/2+ became available in 2019. The experimental results obtained in the first half of 2022 have confirmed the CSM predictions. We also discuss prospects for these studies during the 12-GeV era at JLab using the CLAS12 detector, with experiments that are currently in progress, and canvass the physics motivation for continued studies in this area with a possible increase of the JLab electron beam energy up to 22 GeV. Such an upgrade would finally enable mapping of the dressed quark mass over the full range of distances (i.e., quark momenta) where the dominant part of hadron mass and N* structure emerge in the transition from the strongly coupled to perturbative QCD regimes.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2016

Updates on the Studies of $${\varvec{N}}^\mathbf{*}$$ N * Structure with CLAS and the Prospects with CLAS12

Here, the recent results on $\gamma_vpN^*$ electrocouplings from analyses of the data on exclusive meson electroproduction off protons measured with the CLAS detector at Jefferson Lab are presented. The impact of these results on the exploration of the excited nucleon state structure and non-perturbative strong interaction dynamics behind its formation is outlined. The future extension of these studies in the experiments with the CLAS12 detector in the upgraded Hall-B at JLab will provide for the first time $\gamma_vpN^*$ electrocouplings of all prominent resonances at the still unexplored distance scales that correspond to extremely low (0.05~GeV$^2 < Q^2 <$ 0.5~GeV$^2$) and the highest photon virtualities (5.0~GeV$^2 < Q^2 <$ 12.0~GeV$^2$) ever achieved in the exclusive electroproduction measurements. The expected results will address the most important open problems of the Standard Model: on the nature of more than 98\% of hadron mass, quark-gluon confinement and emergence of the excited nucleon state structure from the QCD Lagrangian, as well as allowing a search for the new states of hadron matter predicted from the first principles of QCD, the so-called hybrid baryons.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2018

Measurement of the Negative Pion and Positive Kaon Total Hadronic Cross Sections on Argon at the LArIAT Experiment

The Liquid Argon Time Projection Chamber (LArTPC) represents one of the most advanced experimental technologies for physics at the Intensity Frontier due to its full 3D-imaging, excellent particle identication and precise calorimetric energy reconstruction. By deploying a LArTPC in a dedicated calibration test beam line at Fermilab, LArIAT (Liquid Argon In A Testbeam) aims to experimentally calibrate this technology in a controlled environment and to provide physics results key to the neutrino oscillation physics and proton decay searches of the Short Baseline Neutrino (SBND, MicroBooNE, ICARUS) and Long Baseline Neutrino programs (DUNE). LArIAT's physics program entails a vast set of topics with a particular focus on the study of nuclear eects such as pion and kaon characteristic interaction modes. This thesis presents two measurements performed for the rst time: the measure- ment of the negative pion total hadronic cross section on argon in the 100-1050 MeV kinetic energy range and the measurement of the positive kaon total hadronic cross section on argon in the 100-650 MeV kinetic energy range. The analyses devised for these measurements use both the core elements of LArIAT: beamline and LArTPC. The rst step in each analysis is the development of an event selection based on beam- line and TPC information geared towards the identication of the hadron of interest. We then proceed to match the beamline candidate to a suitable TPC track. Finally, we apply the \thin slice method" technique and measure the cross section, correcting for background contamination and detector eects. The thin slice technique is a new method to measure hadron-argon cross sections possible only due to the combination of the tracking and calorimetry capability of the LArTPC technology. Albeit never on argon, the hadronic cross section of pions has been extensively measured before on lighter and heavier dierent elements in thin target experiments, leading to solid predictions for measurements on argon. Through the use of a dierent technique, our measurement of the negative pion total hadronic cross section on argon is in general agreement with the predictions by the Geant4 Bertini Cascade model which are based on data from thin target experiments. On the contrary, cross section measurements for kaons are extremely scarce, thus more dicult to model. Our measurement of the positive kaon total hadronic cross section on argon is mostly in tension with the Geant4 prediction over the explored range of energies and provides new experimental data to properly compare existing interaction models. This thesis also reports two ancillary detector physics measurements necessary for the cross section analyses: the measurements of the LArIAT electric eld and calorimetry constants. We developed a technique to measure the LArIAT electric eld using cathode-anode piercing tracks with cosmic data. We applied a new technique for the measurement of the calorimetry calibration constants based on the particles' momentum measurement. The negative pion and the positive kaon total hadronic cross measurements are the rst physics results of the LArIAT experiment and will be the basis for the future LArIAT measurements of pion and kaon cross sections in the exclusive channels. The outcome of these measurements will ultimately enable to quantify and reduce the systematic associated with the hadronic interaction models in neutrino-argon interactions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗