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DOE OSTI2022

NOvA 2020 official data release (13.6E20 neutrino + 12.5E20 antineutrino)

NOvA results of the 2020 joint analysis of nue appearance and numu disappearance data presented in Phys. Rev. D 106, 032004:https://doi.org/10.1103/PhysRevD.106.032004Note: these contained plots are slightly different from the ones shown at NEUTRINO 2020.Exposure: 13.6E20 protons on target, neutrino-enhanced beam12.5E20 protons on target, antineutrino-enhanced beamParameters not constrained by NOvA:- th13 is assumed to be Gaussian, ss2th13 = 0.085 +/- 0.003 (PDG 2019, Phys. Rev. D98, 030001 (2018) and 2019 update, https://pdg.lbl.gov/2019/listings/rpp2019-list-neutrino-mixing.pdf)- ss2th12 = 0.851, dm21=7.53e-5 are fixed at 2019 PDG valuesSignificances are obtained with the Feldman-Cousins procedure.Files contain TGraphs for the following:- ssth23 vs deltaCP 1,2,3 sigma and 90% CL contours, for NO or IO- dmsq32 vs ssth23 1,2,3 sigma and 90% CL contours, for NO or IO- deltaCP profile for NO UO, NO LO, IO LO, IO UO- ssth23 profile for NO, IO- dmsq32 profile for NO UO, NO LO, IO LO, IO UOContour files also include a TMarker with the best-fit parameters (in the NO)An additional file containing the predictions for all channels’ signal and background components computed at the NOvA best-fit oscillation parameters and systematic pull terms. Numu samples include the no-oscillation case as well.Please note that any fits performed with these histograms are not expected to exactly reproduce the official NOvA results as parameterizations of the numerous systematic uncertainties considered in the official fits are not included in this release.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Aerosol Inlets for a Mid-Sized Uncrewed Aerial System (UAS)

The purpose of this technical report is to document the efforts to design and test two inlet systems for aerosol sampling suitable for deployment on a medium-sized fixed-wing Uncrewed Aerial System (UAS). This work, which was supported by the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) user facility, was conducted at the Pacific Northwest National Laboratory (PNNL) for the ARM Aircraft Facility (AAF) starting in November 2017. The current work is a part of AAF efforts to instrument the ArcticShark (a mid-sized UAS owned and operated by the AAF) for atmospheric research and develop a scientific payload for deployment on a similar-sized UAS with minimal adaptation and integration. An aerosol inlet system is necessary to sample and transport ambient air sample to the scientific instrumentation with minimal distortions to the aerosols. Two isokinetic aerosol inlets were designed: the first is a simple passive system for a single instrument suitable to be installed in a wing pylon; the second is a system with active control designed to sample and distribute air among several heterogeneous instruments and to provide basic humidity control of the air sample so that the measured aerosol parameters should correspond to “dry” conditions (a common requirement). Both systems could be easily adapted for deployment on another platform and/or with a different set of instrumentation. Several conducted flight tests showed that the inlets’ performance met our design goals.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2023

Seeing through noise in power laws

Despite widespread claims of power laws across the natural and social sciences, evidence in data is often equivocal. Modern data and statistical methods reject even classic power laws such as Pareto’s law of wealth and the Gutenberg–Richter law for earthquake magnitudes. We show that the maximum-likelihood estimators and Kolmogorov–Smirnov (K-S) statistics in widespread use are unexpectedly sensitive to ubiquitous errors in data such as measurement noise, quantization noise, heaping and censorship of small values. This sensitivity causes spurious rejection of power laws and biases parameter estimates even in arbitrarily large samples, which explains inconsistencies between theory and data. We show that logarithmic binning by powers of λ > 1 attenuates these errors in a manner analogous to noise averaging in normal statistics and that λ thereby tunes a trade-off between accuracy and precision in estimation. Binning also removes potentially misleading within-scale information while preserving information about the shape of a distribution over powers of λ, and we show that some amount of binning can improve sensitivity and specificity of K-S tests without any cost, while more extreme binning tunes a trade-off between sensitivity and specificity. We therefore advocate logarithmic binning as a simple essential step in power-law inference.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2023

Design, Modeling, and Testing of a Novel Inductor for Electric Vehicles: Iron Nitride Soft Magnetic Composites

New technology for electric vehicles (EVs) must meet the requirements of higher energy usage, lower costs, and more sustainable source materials. One promising material for EV power system components is iron nitride (IN) soft magnetic composites (SMCs) because of their competitive magnetic properties and high abundance of the source materials. As part of an ongoing program at Sandia National Laboratories, this project focused on using computer modeling to optimize the prototyping process for an iron nitride SMC toroidal inductor to reach a target inductance of 600 μH. Four inductors with different combinations of wiring (26 AWG and 20 AWG) and vol% loading of iron nitride (65 vol% and 50 vol%) were fabricated at Cal Poly and characterized using an LCR meter. These inductors were also modeled using COMSOL Multiphysics™ with the Magnetic Fields module. The inductance data from the experiment and the model show that the 65 vol% IN prototypes and models agree with about 8% difference, while the 50 vol% IN samples show about a 9% difference between the prototype and the model. These results suggest that the model can predict inductance with both accuracy and precision with low confidence for the given sample size of four. An additional parameter of AC resistance is studied but the AC resistance results from the inductors and from the model generally do not agree closely, suggesting that the current model used in the project does not fully capture the mechanisms behind AC resistance of the inductor. With the focus of the project on inductance, the percent difference results of less than 9% across the four inductors that were tested increases confidence in the model’s predictive capabilities for inductance only. Using the inductance results from both the model and experiment, the final suggested inductor design is a 65 vol% core with 150 windings of 20 AWG wire that is 8 cm across and 1.5 cm tall to reach the inductance goal of 600 μH based on analysis using the optimized COMSOLTM model.

33 ADVANCED PROPULSION SYSTEMS↗

DOE OSTI2022

Aerosol Inlets for a Mid-Sized Uncrewed Aerial System (UAS)

42 ENGINEERING↗

DOE OSTI2026

OSL1 Delivery Lens Design Update [Slides]

By changing 2 surfaces (1 new lens) OSL1 can deliver a 2cm spot size and up to 28 J/cm 2 . This new lens does not have any deleterious first-order ghosts. Further work could allow placement of a relay plane at the sample plane by adjusting an additional parameter (inter-lens spacing, changing a third lens etc.) and changing between configurations by pure lens translation (no lens swapping).

42 ENGINEERING↗

DOE OSTI2024

ℤ2 × ℤ2 Equivariant Quantum Neural Networks: Benchmarking against Classical Neural Networks

This paper presents a comparative analysis of the performance of Equivariant Quantum Neural Networks (EQNNs) and Quantum Neural Networks (QNNs), juxtaposed against their classical counterparts: Equivariant Neural Networks (ENNs) and Deep Neural Networks (DNNs). We evaluate the performance of each network with three two-dimensional toy examples for a binary classification task, focusing on model complexity (measured by the number of parameters) and the size of the training dataset. Our results show that the Z2×Z2 EQNN and the QNN provide superior performance for smaller parameter sets and modest training data samples.

Dong, Zhongtian (ORCID:0000000210003454)↗

DOE OSTI2022

A Constraint on Primordial B-modes from the First Flight of the Spider Balloon-borne Telescope

We present the first linear polarization measurements from the 2015 long-duration balloon flight of Spider, which is an experiment that is designed to map the polarization of the cosmic microwave background (CMB) on degree angular scales. The results from these measurements include maps and angular power spectra from observations of 4.8% of the sky at 95 and 150 GHz, along with the results of internal consistency tests on these data. While the polarized CMB anisotropy from primordial density perturbations is the dominant signal in this region of sky, Galactic dust emission is also detected with high significance. Galactic synchrotron emission is found to be negligible in the Spider bands. We employ two independent foreground-removal techniques to explore the sensitivity of the cosmological result to the assumptions made by each. The primary method uses a dust template derived from Planck data to subtract the Galactic dust signal. A second approach, which constitutes a joint analysis of Spider and Planck data in the harmonic domain, assumes a modified-blackbody model for the spectral energy distribution of the dust with no constraint on its spatial morphology. Using a likelihood that jointly samples the template amplitude and r parameter space, we derive 95% upper limits on the primordial tensor-to-scalar ratio from Feldman–Cousins and Bayesian constructions, finding r < 0.11 and r < 0.19, respectively. Roughly half the uncertainty in r derives from noise associated with the template subtraction. New data at 280 GHz from Spider's second flight will complement the Planck polarization maps, providing powerful measurements of the polarized Galactic dust emission.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2025

On Finding Black Holes in Photometric Microlensing Surveys

There are expected to be millions of isolated black holes in the galaxy resulting from the deaths of massive stars. Measuring the abundance and properties of this remnant population would shed light on the end stages of stellar evolution and the evolution paths of black hole systems. Detecting isolated black holes is currently only possible via gravitational microlensing, which has so far yielded one definitive detection. The difficulty in finding microlensing black holes lies in having to choose a small subset of events, based on characteristics of their light curves, to allocate expensive and scarce follow-up resources to confirm the identity of the lens. Current methods either rely on simple cuts in parameter space without using the full distribution information or are only effective on small subsets of events. In this paper, we present a new lens classification method. The classifier takes in posterior constraints on light-curve parameters and combines them with a Galactic simulation to estimate the lens class probability. This method is flexible and can be used with any set of microlensing light-curve parameters, making it applicable to large samples of events. We make this classification framework available via the popclass Python package. We apply the classifier to ~10,000 microlensing events from the Optical Gravitational Lensing Experiment survey and find 23 high-probability black hole candidates. Our classifier also suggests that the only known isolated black hole is an observational outlier, according to current Galactic models, and the allocation of astrometric follow-up on this event was a high-risk strategy.

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS1970

Computer simulation of Saturn 5 response to pre-launch wind loads

A digital computer program is described which was developed to estimate Saturn 5 response to prelaunch wind conditions at Cape Kennedy. The program computes displacement and bending moment statistics as a function of parameters defining the atmospheric environment. A sample problem is provided to illustrate utilization of the program.

Coffin, T.↗

NASA NTRS1974

Statistical analysis of general aviation VG-VGH data

To represent the loads spectra of general aviation aircraft operating in the Continental United States, VG and VGH data collected since 1963 in eight operational categories were processed and analyzed. Adequacy of data sample and current operational categories, and parameter distributions required for valid data extrapolation were studied along with envelopes of equal probability of exceeding the normal load factor (n sub z) versus airspeed for gust and maneuver loads and the probability of exceeding current design maneuver, gust, and landing impact n sub z limits. The significant findings are included.

Clay, L. E.↗

NASA NTRS1972

Electron microprobe analysis program for biological specimens: BIOMAP

BIOMAP is a Univac 1108 compatible program which facilitates the electron probe microanalysis of biological specimens. Input data are X-ray intensity data from biological samples, the X-ray intensity and composition data from a standard sample and the electron probe operating parameters. Outputs are estimates of the weight percentages of the analyzed elements, the distribution of these estimates for sets of red blood cells and the probabilities for correlation between elemental concentrations. An optional feature statistically estimates the X-ray intensity and residual background of a principal standard relative to a series of standards.

Edwards, B. F.↗

NASA NTRS1977

Calculation of sheath and wake structure about a pillbox-shaped spacecraft in a flowing plasma

A computer program was used for studies of the disturbed zones around bodies in flowing plasmas, particularly spacecraft and their associated sheaths and wakes. The program solved a coupled Poisson-Vlasov system of nonlinear partial differential integral equations to obtain distributions of electric potential and ion and electron density about a finite length cylinder in a plasma flow at arbitrary ion Mach numbers. The approach was applicable to a larger range of parameters than other available approaches. In sample calculations, bodies up to 100 Debye lengths in radius were treated, that is, larger than any previously treated realistically. Applications were made to in-situ satellite experiments.

Parker, L. W.↗

NASA NTRS1979

Problems with the interpretation of paleomagnetic measurements due to studies of basalts from the Paleovolcano Vogelsberg in Hessen

The palaeomagnetic parameters of more than 5,000 samples of cores taken from 33 drilling holes through innumerable basalt units of the Vogelsberg Paleovolcano in Hessen were measured. Measurements of specimens of thin and thick layers without any gap proved that inclination, natural remanence, susceptibility and Konigsberger factor were dependent on their distance from the surface of units, layers, lamelles, etc. Therefore, representative data for the evaluation of palaeomagnetic measurements can be expected only in the interior part of lava flows and intrusions. The statistic method which enclosed all values of measurements gave significant data which was not appropriate for the interpretation of palaeomagnetic and geological events.

Schenk, E.↗

NASA NTRS1980

Statistical aspects of carbon fiber risk assessment modeling

The probabilistic and statistical aspects of the carbon fiber risk assessment modeling of fire accidents involving commercial aircraft are examined. Three major sources of uncertainty in the modeling effort are identified. These are: (1) imprecise knowledge in establishing the model; (2) parameter estimation; and (3)Monte Carlo sampling error. All three sources of uncertainty are treated and statistical procedures are utilized and/or developed to control them wherever possible.

Gross, D.↗

NASA NTRS1980

A contribution to the knowledge of HMX decomposition and application of results

The decomposition of cyclotramethylenetetranitramine (HMX) in the solid and liquid phase was studied by isothermal and nonisothermal heating at atmospheric pressure. Decomposition rates of solid HMX changed with sample size and gaseous environment. Kinetic parameters were obtained from weight loss measurements in the temperature range 229 C - 269 C. These tests also yielded highly porous solid residues. Qualitative aspects of solid and liquid phase decomposition of HMX with additives were also investigated in isothermal and nonisothermal tests.

Kraeutle, K. J.↗

NASA NTRS1978

Shuttle applications in tropospheric air quality observations

The role which might be played by the space shuttle in obtaining data which describes the air quality of the north-eastern United States was investigated. The data requirements of users, a model for statistical interpretation of the observations, the influence of orbit parameters on the spatial and temporal sampling and an example of application of the the model were considered.

Friedman, E.↗

NASA NTRS1984

Oceanographic biooptical profiling system

A new oceanographic instrument to measure underwater optical, biological, and physical properties has been designed, built, and used extensively at sea. The new instrument system is a significant advance that permits optimum sampling strategies using ship, aircraft, and satellite optical sensors for ocean research. The design criteria for the biooptical profiling system included the rapid acquisition of data to accommodate shipboard synoptic sampling; the measurement of the necessary parameters for providing appropriate contemporaneous surface data for remote sensors; the compatibility of the data acquisition system with conventional conductivity temperature depth-type cables and winches on the oceanographic fleet; the capability of real-time display of data along with rapid preliminary data reduction at sea. The primary instrument package in this profiling system is a new microprocessor controlled multiwavelength spectroradiometer. A description of the instrument and examples of data are presented.

Smith, R. C.↗