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DOE OSTI2026

Determining Optimal Magnetometer Configuration on MAGIS-100

Long-baseline atom interferometers such as the Matter-wave Atomic Gradiometer Interferometric Sensor (MAGIS-100) require stringent control and continuous characterization of background magnetic fields and spatial gradients to prevent systemic phase shifts that mimic ultralight dark matter or gravitational wave signatures. Because direct sensor placement within the ultra-high vacuum beam pipe is infeasible, in-situ magnetic field monitoring relies on external sensor arrays situated in the surrounding annular region. This work demonstrates a field reconstruction framework for a 5.3-meter MAGIS-100 modular section using finite-element Opera simulations. Transverse magnetic fields are expanded using a cylindrical multipole framework as informed by Fermilab’s Muon g-2 experiment, with magnetometer array configurations optimized via Fisher information matrix D-optimality. Inverting external sensor readings through a Gauss-Newton scheme recovers interior tube fields across distinct axial positions. In the discontinuity-averse uniform region (slice pair P4), the model achieves sub-noise-floor performance with a cross-validated root-mean-square error (RMSE) of $6.7227 \times 10^{-4}\text{ A/m}$ ($0.845\times$ sensor noise floor) and an interior field coefficient of variation of $1.71\%$. An elbow criterion in the Fisher bounds establishes $n_{\text{max}} = 2$ as the optimal multipole truncation order to prevent noise amplification from over-parameterization, with $n_{\text{max}} = 3$ (sextupole) order chosen for analysis to demonstrate further complexity and cross-pair comparison. Furthermore, analytical differentiation of the fitted multipole coefficients yields dense spatial maps of the transverse Jacobian gradient matrix $\nabla \mathbf{H}$ along with propagated $1\sigma$ uncertainty bounds across the beam region ($r \le 2.75\text{ in}$). This operational framework confirms that external magnetometer arrays can reliably monitor magnetic field uniformity and spatial gradients along the 100-meter flight path given appropriate sampling for any complexity order.

Appleby, Darwin [William Rainey Harper Coll.] (ORC↗

DOE OSTI2016

Quantifying discordance in the 2015 Planck CMB spectrum

We examine the internal consistency of the Planck 2015 cosmic microwave background (CMB) temperature anisotropy power spectrum. We show that tension exists between cosmological constant cold dark matter (ΛCDM) model parameters inferred from multipoles ℓ<1000 (roughly those accessible to Wilkinson Microwave Anisotropy Probe), and from ℓ⩾1000, particularly the CDM density, Ω{sub c}h{sup 2}, which is discrepant at 2.5σ for a Planck -motivated prior on the optical depth, τ=0.07±0.02. We find some parameter tensions to be larger than previously reported because of inaccuracy in the code used by the Planck Collaboration to generate model spectra. The Planck ℓ⩾1000 constraints are also in tension with low-redshift data sets, including Planck ’s own measurement of the CMB lensing power spectrum (2.4σ), and the most precise baryon acoustic oscillation scale determination (2.5σ). The Hubble constant predicted by Planck from ℓ⩾1000, H{sub 0}=64.1±1.7 km s{sup −1} Mpc{sup −1}, disagrees with the most precise local distance ladder measurement of 73.0±2.4 km s{sup −1} Mpc{sup −1} at the 3.0σ level, while the Planck value from ℓ<1000, 69.7±1.7 km s{sup −1} Mpc{sup −1}, is consistent within 1σ. A discrepancy between the Planck and South Pole Telescope high-multipole CMB spectra disfavors interpreting these tensions as evidence for new physics. We conclude that the parameters from the Planck high-multipole spectrum probably differ from the underlying values due to either an unlikely statistical fluctuation or unaccounted-for systematics persisting in the Planck data.

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS1972

The induced magnetic field of the moon - Conductivity profiles and inferred temperature.

Electromagnetic induction in the moon driven by fluctuations of the interplanetary magnetic field is used to determine the lunar bulk electrical conductivity. The earlier data are now augmented by an order of magnitude. The present data clearly show the north-south and east-west transfer function difference as well as the high-frequency rollover suggested earlier. The difference is shown to be compatible over the midfrequency range (0.001 to 0.01 Hz) with a noise source associated with the compression of the local remanent field by solar wind dynamic pressure fluctuations. The rollover of the transfer functions is shown to result from higher order magnetic multipole radiation; electric multipoles appear supressed, although a vestigial TM interaction may still be present. Models for two, three, and four layer; current layer, double current layer, and core plus current layer moons are generated by inversion of the data, using a theory that incorporates higher-order multipoles.

Sonett, C. P.↗

NASA NTRS1992

Theoretical shell-model signatures in heavy-ion, coherent pion production

A comprehensive summary of a many-body, microscopic, particle-hole formalism is presented that describes coherent, subthreshold, pion production in peripheral, heavy-ion collisions. The formalism uses a new separable model transition interaction that produces Delta-hole states in either the projectile or target nucleus. Shell-model states described by harmonic oscillator functions are used in the calculation of Delta formation and decay and Lorentz-contraction effects of the nucleus not at rest are included. An analytical expression to lowest multipole order for the differential cross section is examined. The sensitivity of the theoretical results to the shell-model states is determined with preliminary shape results compared with data. The effects of higher multipoles are examined with attention paid to the second-order multipole value.

Maung, Khin M.↗

NASA NTRS2002

The Anisotropy of the Microwave Background to l = 3500: Deep Field Observations with the Cosmic Background Imager

We report measurements of anisotropy in the cosmic microwave background radiation over the multipole range l approximately 200 (right arrow) 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power with increasing l first reported in earlier measurements with this instrument, and extend the observations of this decline in power out to l approximately 2000. The decline in power is consistent with the predicted damping of primary anisotropies. At larger multipoles, l = 2000-3500, the power is 3.1 sigma greater than standard models for intrinsic microwave background anisotropy in this multipole range, and 3.5 sigma greater than zero. This excess power is not consistent with expected levels of residual radio source contamination but, for sigma 8 is approximately greater than 1, is consistent with predicted levels due to a secondary Sunyaev-Zeldovich anisotropy. Further observations are necessary to confirm the level of this excess and, if confirmed, determine its origin.

Mason, B. S.↗

NASA NTRS2007

Anatomy of the Binary Black Hole Recoil: A Multipolar Analysis

We present a multipolar analysis of the recoil velocity computed in recent numerical simulations of binary black hole coalescence, for both unequal masses and non-zero, non-precessing spins. We show that multipole moments up to and including 1 = 4 are sufficient to accurately reproduce the final recoil velocity (= 98%) and that only a few dominant modes contribute significantly to it (2 95%). We describe how the relative amplitude, and more importantly, the relative phase, of these few modes control the way in which the recoil builds up throughout the inspiral, merger, and ring-down phases. We also find that the numerical results can be reproduced, to a high level of accuracy, by an effective Newtonian formula for the multipole moments obtained by replacing in the Newtonian formula the radial separation with an effective radius computed from the numerical data. Beyond the merger, the numerical results are reproduced by a superposition of three Kerr quasi-normal modes. Analytic formulae, obtained by expressing the multipole moments in terms of the fundamental QNMs of a Kerr BH, are able to explain the onset and amount of '.anti-kick" for each of the simulations. Lastly, we apply this multipolar analysis to understand the remarkable difference between the amplitudes of planar and non-planar kicks for equal-mass spinning black holes.

Schnittman, Jeremy↗

NASA NTRS2005

Asymmetric Electrostatic Radiation Shielding for Spacecraft

A paper describes the types, sources, and adverse effects of energetic-particle radiation in interplanetary space, and explores a concept of using asymmetric electrostatic shielding to reduce the amount of such radiation impinging on spacecraft. Typically, such shielding would include a system of multiple inflatable, electrically conductive spheres deployed in clusters in the vicinity of a spacecraft on lightweight structures that would maintain the spheres in a predetermined multipole geometry. High-voltage generators would maintain the spheres at potential differences chosen in conjunction with the multipole geometry so that the resulting multipole field would gradually divert approaching energetic atomic nuclei from a central region occupied by the spacecraft. The spheres nearest the center would be the most positive, so as to repel the positively charged impinging nuclei from the center. At the same time, the monopole potential of the overall spacecraft-and-shielding system would be made negative so as to repel thermal electrons. The paper presents results of computational simulations of energetic-particle trajectories and shield efficiency for a trial system of 21 spheres arranged in three clusters in an overall linear quadrupole configuration. Further development would be necessary to make this shielding concept practical.

Metzger, Philip T.↗

NASA NTRS2011

The Atacama Cosmology Telescope: Calibration with the Wilkinson Microwave Anisotropy Probe Using Cross-Correlations

We present a new calibration method based on cross-correlations with the Wilkinson Microwave Anisotropy Probe (WMAP) and apply it to data from the Atacama Cosmology Telescope (ACT). ACT's observing strategy and mapmaking procedure allows an unbiased reconstruction of the modes in the maps over a wide range of multipoles. By directly matching the ACT maps to WMAP observations in the multipole range of 400 < I < 1000, we determine the absolute calibration with an uncertainty of 2% in temperature. The precise measurement of the calibration error directly impacts the uncertainties in the cosmological parameters estimated from the ACT power spectra. We also present a combined map based on ACT and WMAP data that has a high signal-to-noise ratio over a wide range of multipoles.

Hajian, Amir↗

DOE OSTI2026

In-Situ Magnetic Field Reconstruction in the MAGIS-100 Experiment

Appleby, Darwin [William Rainey Harper Coll.; Ferm↗

DOE OSTI2013

THE Q/U IMAGING EXPERIMENT INSTRUMENT

The Q/U Imaging ExperimenT (QUIET) is designed to measure polarization in the cosmic microwave background, targeting the imprint of inflationary gravitational waves at large angular scales({approx}1 Degree-Sign ). Between 2008 October and 2010 December, two independent receiver arrays were deployed sequentially on a 1.4 m side-fed Dragonian telescope. The polarimeters that form the focal planes use a compact design based on high electron mobility transistors (HEMTs) that provides simultaneous measurements of the Stokes parameters Q, U, and I in a single module. The 17-element Q-band polarimeter array, with a central frequency of 43.1 GHz, has the best sensitivity (69 {mu}Ks{sup 1/2}) and the lowest instrumental systematic errors ever achieved in this band, contributing to the tensor-to-scalar ratio at r < 0.1. The 84-element W-band polarimeter array has a sensitivity of 87 {mu}Ks{sup 1/2} at a central frequency of 94.5 GHz. It has the lowest systematic errors to date, contributing at r < 0.01. The two arrays together cover multipoles in the range l {approx} 25-975. These are the largest HEMT-based arrays deployed to date. This article describes the design, calibration, performance, and sources of systematic error of the instrument.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2021

Ordering effects on deformation substructures and strain hardening behavior of a CrCoNi based medium entropy alloy

Here, a CrCoNi based medium entropy alloy with small additions of Ti, Al and Nb (denoted as (CrCoNi) 93 Al 4 Ti 2 Nb) in the as-quenched condition, exhibits tensile properties comparable to those of the equiatomic CrCoNi alloy at room temperature. Dark field transmission electron microscopy (TEM), atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) together with atom probe tomography (APT) show that spatially-localized long range ordering (LRO) L1 2 domains exist in this alloy. The evolution of deformation substructure with plastic deformation in this alloy was characterized using electron backscatter diffraction (EBSD), electron channeling contrast imaging (ECCI) and STEM based techniques including the recently developed weak beam dark field STEM imaging. Plastic deformation occurs by the slip of a/2<110>dislocations, which are narrowly dissociated into Shockley partial dislocations on {111} slip planes. Their dissociation distances in the (CrCoNi) 93 Al 4 Ti 2 Nb alloy are much smaller than the widths of the corresponding partials in the equiatomic CrCoNi alloy due to one or more of the minor alloying elements (Al, Ti, Nb). Dislocation slip in this alloy has a pronounced planar character. The leading dislocations in slip bands glide as pairs due to the existence of LRO domains. Multipoles were formed through the slip of dislocations with opposite signs on adjacent {111} slip planes. Those multipoles serve as building blocks for the formation of subgrain structures consisting of fine slip bands. The distances between slip bands were continuously refined during plastic deformation and dynamic refinement of slip bands plays a crucial role in strain hardening. The effects of LRO domains on planar dislocation slip, the deactivation of deformation twinning and strain hardening of this alloy are discussed.

36 MATERIALS SCIENCE↗

DOE OSTI2014

Radiative recombination data for tungsten ions: III. W{sup 14+}–W{sup 23+}

This paper completes the cycle of our calculations of the radiative recombination and photoionization data for tungsten ions. Presented here are the photoionization and radiative recombination cross sections, radiative recombination rate coefficients, and radiated power loss rate coefficients for ten tungsten impurity ions from W{sup 14+} to W{sup 23+}. These data are required in diagnostics and modeling fusion plasmas studied in such devices as ITER, ASDEX Upgrade, and EBIT. Partial photoionization cross sections have been fitted by an analytical expression with five fit parameters tabulated here. Total radiative recombination cross sections are presented in the electron energy range from 1 eV to ∼80 keV. Radiative recombination rates and radiated power loss rates are given in the temperature range from 10{sup 4} K to 10{sup 9} K. Calculations have been performed on the basis of the fully relativistic treatment of photoionization and radiative recombination taking into account all significant multipoles of the radiative field. Electron wave functions have been obtained by the Dirac–Fock method with the proper consideration of the electron exchange. The relativistic Maxwell–Jüttner distribution of continuum electrons has been used in calculations of radiative recombination rates and radiated power loss rates. This decreases values of the rates noticeably at a high temperature as compared to the usual non-relativistic Maxwell–Boltzmann distribution. -- Highlights: •Radiative recombination data for ten tungsten ions W{sup 14+}–W{sup 23+} are presented. •Photoionization cross sections are also given. •Calculations are fully relativistic including all multipoles of the radiative field. •We use the Dirac–Fock method to obtain the electron wave functions. •The data are required for diagnostics and modeling fusion plasmas studied in ITER.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2014

Suppression of unimolecular decay of laser desorbed peptide and protein ions by entrainment in rarefied supersonic gas jets under weak electric fields

Unimolecular decay of sample ions imposes a limit on the usable laser fluence in matrix-assisted laser desorption/ionization (MALDI) ion sources. Traditionally, some modest degree of collisional sample ion cooling has been achieved by connecting MALDI ion sources directly to gas-filled radio frequency (RF) multipoles. It was also discovered in the early 1990s that gas-filled RF multipoles exhibit increased ion transmission efficiency due to collisional ion focusing effects. This unexpected experimental finding was later supported by elementary Monte Carlo simulations. Both experiments and simulations assumed a resting background gas with typical pressures of the order of 1 Pa. However, considerable additional improvements can be achieved if laser desorbed sample ions are introduced immediately after desorption, still within the ion source, in an axisymmetric rarefied supersonic gas jet with peak pressure of the order of 100 Pa and flow velocities >300 m/s, and under weak electric fields. We describe here the design principle and report performance data of an ion source coined “MALDI-2,” which incorporates elements of both rarefied aerodynamics and particle optics. Such a design allows superb suppression of metastable fragmentation due to rapid collisional cooling in <10 μs and nearly perfect injection efficiency into the attached RF ion guide, as numerous experiments have confirmed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2016

Localized surface plasmon mediated energy transfer in the vicinity of core-shell nanoparticle

Multipole spectral expansion based theory of energy transfer interactions between a donor and an acceptor molecule in the vicinity of a core-shell (nanoshell or core@shell) based plasmonic nanostructure is developed. In view of the diverse applications and rich plasmonic features such as tuning capability of surface plasmon (SP) frequencies, greater sensitivity to the change of dielectric environment, controllable redirection of electromagnetic radiation, closed form expressions for Energy Transfer Rate Enhancement Factor (ETREF) near core-shell particle are reported. The dependence of ETREF on different parameters is established through fitting equations, perceived to be of key importance for developing appropriate designs. The theoretical approach developed in the present work is capable of treating higher order multipoles, which, in turn, are also shown to play a crucial role in the present context. Moreover, closed form expressions derived in the present work can directly be used as formula, e.g., for designing SP based biosensors and estimating energy exchange between proteins and excitonic interactions in quantum dots.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2021

Too big, too small, or just right? A benchmark assessment of density functional theory for predicting the spatial extent of the electron density of small chemical systems

Multipole moments are the first-order responses of the energy to spatial derivatives of the electric field strength. The quality of density functional theory prediction of molecular multipole moments thus characterizes errors in modeling the electron density itself, as well as the performance in describing molecules interacting with external electric fields. However, only the lowest non-zero moment is translationally invariant, making the higher-order moments origin-dependent. Therefore, instead of using the 3 × 3 quadrupole moment matrix, we utilize the translationally invariant 3 × 3 matrix of second cumulants (or spatial variances) of the electron density as the quantity of interest (denoted by K). The principal components of K are the square of the spatial extent of the electron density along each axis. A benchmark dataset of the principal components of K for 100 small molecules at the coupled cluster singles and doubles with perturbative triples at the complete basis set limit is developed, resulting in 213 independent K components. The performance of 47 popular and recent density functionals is assessed against this Var213 dataset. Several functionals, especially double hybrids, and also SCAN and SCAN0 predict reliable second cumulants, although some modern, empirically parameterized functionals yield more disappointing performance. The H, Li, and Be atoms, in particular, are challenging for nearly all methods, indicating that future functional development could benefit from the inclusion of their density information in training or testing protocols.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2011

LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA

We have investigated the angular correlation in the recent cosmic microwave background data. In addition to the known large-angle correlation anomaly, we find the lack of correlation at small angles with high statistical significance. We have investigated various non-cosmological contamination as well as the Wilkinson Microwave Anisotropy Probe (WMAP) team's simulated data. However, we have not found a definite cause. In the angular power spectrum of WMAP data, there exists anomalous odd-parity preference at low multipoles. Noting the equivalence between the power spectrum and the correlation, we have investigated the association between the lack of large-angle correlation and the odd-parity preference. From our investigation, we find that the odd-parity preference at low multipoles is, in fact, a phenomenological origin of the lack of large-angle correlation. Further investigation is required to find out whether the origin of the anomaly is cosmological or due to unaccounted systematics. The data from the Planck surveyor, which has systematics distinct from WMAP, will greatly help us to resolve its origin.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2012

COSMIC MICROWAVE BACKGROUND INDUCED POLARIZATION FROM SINGLE SCATTERING BY CLUSTERS OF GALAXIES AND FILAMENTS

We present light-cone-integrated simulations of the cosmic microwave background (CMB) polarization signal induced by a single scattering in the direction of clusters of galaxies and filaments. We characterize the statistical properties of the induced polarization signals from the presence of the CMB quadrupole component (pqiCMB) and as the result of the transverse motion of ionized gas clouds with respect to the CMB rest frame (p{beta}{sup 2}{sub t}SZ). From adiabatic N-body/hydrodynamic simulations, we generated 28 random sky patches integrated along the light cone, each with about 0.86 deg{sup 2} and angular resolution of 6''. Our simulation method involves a box-stacking scheme that allows to reconstruct the CMB quadrupole component and the gas physical properties along the line of sight. We find that the linear polarization degree in the logarithmic scale of both effects follows approximately a Gaussian distribution and the mean total signal is about 10{sup -8} and 10{sup -10} for the pqiCMB and p{beta}{sup 2}{sub t}SZ effects, respectively. The polarization angle is consistent with a flat distribution in both cases. From the mean distributions of the polarization degree with redshift, the highest peak is found at z {approx_equal} 1 for the induced CMB quadrupole and at z {approx_equal} 0.5 for the kinematic component. Our results suggest that most of the contribution for the total polarization signal arises from z {approx}< 4 for the pqiCMB and z {approx}< 3 for p{beta}{sup 2}{sub t}SZ. The spectral dependency of both integrated signals is strong, increasing with the frequency, especially in the case of the p{beta}{sup 2}{sub t}SZ signal, which increases by a factor of 100 from 30 GHz to 675 GHz. The maxima values found at the highest frequency are about 3 {mu}K and 13 {mu}K for the pqiCMB and p{beta}{sup 2}{sub t}SZ, respectively. The angular power spectra of these effects peak at large multipoles l > 10{sup 4}, being of the order of 10{sup -5} {mu}K{sup 2} for pqiCMB polarization and 10{sup -7} {mu}K{sup 2} for the p{beta}{sup 2}{sub t}SZ effect. Therefore, these effects will not be a relevant source of contamination for measurements of the primary polarization modes, and at larger multipoles of roughly l > 40, 000, pqiCMB may be the dominant component over the primary and lensing signals.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2013

LOW-LATITUDE CORONAL HOLES, DECAYING ACTIVE REGIONS, AND GLOBAL CORONAL MAGNETIC STRUCTURE

We study the relationship between decaying active-region magnetic fields, coronal holes, and the global coronal magnetic structure using Global Oscillations Network Group synoptic magnetograms, Solar TErrestrial RElations Observatory extreme-ultraviolet synoptic maps, and coronal potential-field source-surface models. We analyze 14 decaying regions and associated coronal holes occurring between early 2007 and late 2010, 4 from cycle 23 and 10 from cycle 24. We investigate the relationship between asymmetries in active regions' positive and negative magnetic intensities, asymmetric magnetic decay rates, flux imbalances, global field structure, and coronal hole formation. Whereas new emerging active regions caused changes in the large-scale coronal field, the coronal fields of the 14 decaying active regions only opened under the condition that the global coronal structure remained almost unchanged. This was because the dominant slowly varying, low-order multipoles prevented opposing-polarity fields from opening and the remnant active-region flux preserved the regions' low-order multipole moments long after the regions had decayed. Thus, the polarity of each coronal hole necessarily matched the polar field on the side of the streamer belt where the corresponding active region decayed. For magnetically isolated active regions initially located within the streamer belt, the more intense polarity generally survived to form the hole. For non-isolated regions, flux imbalance and topological asymmetry prompted the opposite to occur in some cases.

79 ASTRONOMY AND ASTROPHYSICS↗