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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Final Report on the Measurement of the Positive Muon Anomalous Magnetic Moment at Fermilab to 127 ppb

This report details the final measurement of the muon magnetic anomaly, $a_μ=(g_μ-2)/2$, by the Muon $g-2$ experiment at Fermi National Accelerator Laboratory (FNAL), using positive muons collected from 2021 to 2023. The value of $a_μ$ is determined from the ratio of the anomalous spin precession frequency to the shielded proton precession frequency in the muon storage ring magnetic field, combined with external constants known at the 22 ppb level. The new dataset, containing over $2.5$ times the statistics of our previous results, yields $a_μ=116\,592\,0710(162)\times 10^{-12}$ (139 ppb), or $a_μ=116\,592\,0705(148)\times 10^{-12}$ (127 ppb) when combined with our previous results. The new experimental world average, dominated by the measurements at FNAL, is $a_μ^{\text{Exp}}=116\,592\,0715(145)\times 10^{-12}$ (124 ppb).

Aguillard, D. P. [U. Michigan, Ann Arbor] (ORCID:0↗
DOE OSTI2017

Developing the Precision Magnetic Field for the E989 Muon g{2 Experiment

The experimental value of $(g\hbox{--}2)_\mu$ historically has been and contemporarily remains an important probe into the Standard Model and proposed extensions. Previous measurements of $(g\hbox{--}2)_\mu$ exhibit a persistent statistical tension with calculations using the Standard Model implying that the theory may be incomplete and constraining possible extensions. The Fermilab Muon g-2 experiment, E989, endeavors to increase the precision over previous experiments by a factor of four and probe more deeply into the tension with the Standard Model. The $(g\hbox{--}2)_\mu$ experimental implementation measures two spin precession frequencies defined by the magnetic field, proton precession and muon precession. The value of $(g\hbox{--}2)_\mu$ is derived from a relationship between the two frequencies. The precision of magnetic field measurements and the overall magnetic field uniformity achieved over the muon storage volume are then two undeniably important aspects of the e xperiment in minimizing uncertainty. The current thesis details the methods employed to achieve magnetic field goals and results of the effort.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2015

Vulnerability of Karangkates dams area by means of zero crossing analysis of data magnetic

Study with entitled Vulnerability Karangkates Dam Area By Means of Zero Crossing Analysis of Data Magnetic has been done. The study was aimed to obtain information on the vulnerability of two parts area of Karangkates dams, i.e. Lahor dam which was inaugurated in 1977 and Sutami dam inaugurated in 1981. Three important things reasons for this study are: 1). The dam age was 36 years old for Lahor dam and 32 years old for Sutami dam, 2). Geologically, the location of the dams are closed together to the Pohgajih local shear fault, Selorejo local fault, and Selorejo limestone-andesite rocks contact plane, and 3). Karangkates dams is one of the important Hydro Power Plant PLTA with the generating power of about 400 million KWH per year from a total of about 29.373MW installed in Indonesia. Geographically, the magnetic data acquisition was conducted at coordinates (112.4149oE;-8.2028oS) to (112.4839oE;-8.0989oS) by using Proton Precession Magnetometer G-856. Magnetic Data acquisition was conducted in the radial direction from the dams with diameter of about 10 km and the distance between the measurements about 500m. The magnetic data acquisition obtained the distribution of total magnetic field value in the range of 45800 nT to 44450 nT. Residual anomalies obtained by doing some corrections, including diurnal correction, International Geomagnetic Reference Field (IGRF) correction, and reductions so carried out the distribution of the total magnetic field value in the range of -650 nT to 700 nT. Based on the residual anomalies, indicate the presence of 2 zones of closed closures dipole pairs at located in the west of the Sutami dam and the northwest of the Lahor dam from 5 total zones. Overlapping on the local geological map indicated the lineament of zero crossing patterns in the contour of residual anomaly contour with the Pohgajih shear fault where located at about 4 km to the west of the Sutami dam approximately and andesite-limestone rocks contact where located at about 6 km to the west of the Lahor dam approximately. These shown a possible of vulnerability on geohazards at the west zone of the Karangkates (Lahor-Sutami) dams area if there are triggers by the vibration (earthquake) on the Pohgajih shear fault, andesite-limestone contact plane, and instability rocks on two zones of closed closure dipole pairs area. Reality, on the location of the study shown some local landslide at the several locations and the main road that need considering for disaster mitigation.

58 GEOSCIENCES↗
NASA NTRS1993

Airborne gravity and other geophysical techniques for understanding the lithosphere beneath the West Antarctic Ice Sheet

As part of a program entitled Corridor Aerogeophysics of the Southeastern Ross Transect Zone (CASERTZ), an aerogeophysical platform was developed to study the interaction of geological and glaciological processes in West Antarctica. A de Havilland Twin Otter was equipped with an ice-penetrating radar, a proton precession magnetometer, an airborne gravity system, and a laser altimeter. The 60-MHz ice-penetrating radar can recover sub-ice topography with an accuracy of about 10 m through 3 km of comparatively warm West Antarctic ice, while the laser altimeter profiling of the ice surface is accurate to approximately 1 m. The magnetic field observations are accurate to several nT, and the gravity measurements are accurate to better than 3 mGal. The aircraft is navigated by a local radio transponder network, while differential positioning techniques based on the Global Positioning System (GPS) satellites are used for recovering high-resolution horizontal and vertical positions. Attitude information from an inertial navigation system is used to correct the laser altimetry and a digital pressure transducer is used to recover vertical positions and accelerations in the absence of satellite positioning. Continuous base-station observations are made for the differential GPS positioning and the removal of ionospheric noise from the airborne magnetometer measurements.

Bell, Robin E.↗
NASA NTRS1992

Survey Parameters and Availability of Low-level Aeromagnetic Data for Geomagnetic Field Modelling

Since aeromagnetic surveying started immediately after World War II, a considerable area of the earth's surface both onshore (in excess of 25 million sq. km) has been magnetically surveyed. For about the first 15 years or so, fluxgate magnetometers were employed in aeromagnetic surveys, but the introduction of proton free-precession magnetometers resulted in absolute readings being recorded. Proton precession magnetometers have now been replaced to a large extent by the more sensitive optical absorption magnetometers. Some care has to be taken to calibrate aeromagnetic survey systems and this is best done using a calibration range tied to a magnetic observatory so that accuracies of 10nT or better are achieved for the total field values recorded. Survey navigation has always posed a problem for aeromagnetic surveys, especially offshore. Over land, vertically pointed 35 mm cameras were initially used to recover the aircraft track using a combination of aerial photos and topographic maps. Over featureless areas, it was necessary to utilize existing electronic positioning systems such as Loran C or set up special navigation systems. The advent of the satellite-based Global Positioning Systems (GPS) has to a larger extent solved the navigational problem because there is now almost continuous worldwide coverage to 10 m accuracy in the differential mode. The resultant aeromagnetic data is normally compiled into contour maps in which the diurnal variation and aircraft heading effects are removed. The resultant digital data are normally made publicly available both in gridded and profile form along with the published contour maps. Most aeromagnetic coverage has been obtained in the developed western countries, but elsewhere a considerable amount of surveying has been carried out; as an example, some 80 percent of Africa has been surveyed mostly as a result of aid programs. The data is usually held by the national geological survey or equivalent organizations, but in a number of cases the data (e.g., for the Magnetic Anomaly Map of North America) is also held by the World Data Centres.

Hood, Peter↗
DOE OSTI2021

High-accuracy absolute magnetometry with application to the Fermilab Muon g-2 experiment

We present details of a high-accuracy absolute scalar magnetometer based on pulsed proton NMR. The B-field magnitude is determined from the precession frequency of proton spins in a cylindrical sample of water after accounting for field perturbations from probe materials, sample shape, and other corrections. Features of the design, testing procedures, and corrections necessary for qualification as an absolute scalar magnetometer are described. The device was tested at B = 1.45 T but can be modified for a range exceeding 1–3 T. The magnetometer was used to calibrate other NMR magnetometers and measure absolute magnetic field magnitudes to an accuracy of 19 parts per billion as part of a measurement of the muon magnetic moment anomaly at Fermilab.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2024

Measurement of the muon spin precession frequency using the straw tracking detectors at the Fermilab Muon g-2 experiment

The measurement of the anomalous magnetic dipole moment of the muon ($a_{\mu}$) has long stood as an excellent precision test of the Standard Model (SM). The Fermilab Muon g-2 experiment has recently finished data-taking and in July 2023 published its latest determination of $a_\mu$ with a world-leading precision of 0.2\,ppm. In this publication, it surpassed the systematic uncertainty goal defined in the TDR. The analyses of a dataset approximately four times larger than this recent publication is now underway. The principle measurement of the Muon g-2 experiment measures $a_{\mu}$ by taking the ratio of two frequencies; the anomalous precession frequency ($\omega_a$) and the muon-weighted magnetic field of the experiment's storage ring measured from the precession frequency of protons in water using nuclear magnetic resonance (NMR) probes. In all publications to date, $\omega_a$ has been determined using energy deposits in the 24 calorimeters. However, the Fermilab experiment has t wo straw tracker detectors measuring the time and momentum of charged particles which can in principle also be used to to measure $\omega_a$ and such a measurement can provide an invaluable cross-check of the calorimeter result with different, and reduced, systematic uncertainties. This thesis presents the first (blinded) determination of $\omega_a$ using just charged tracks from the straw tracking detectors as opposed to calorimeter energy deposits. This analysis was undertaken using the Run-2/3 dataset which represents approximately 25\% of the final dataset. A total uncertainty of 2.19\,ppm on $\omega_a$ was obtained which is dominated by the statistical uncertainty of 2.16\,ppm. Additionally two new methodologies important to the analysis of the straw tracking data have been developed: one to better determine the track arrival time ($t_0$) and one to determine the level of pileup in the tracking detectors. The new $t_0$ algorithm which incorporates angular information improves t he resolution on the determination of the $t_0$ by a factor of two and results in 19\% more tracks being successfully reconstructed. The data from the trackers is also used to determine the beam profile that weights the magnetic field in the determination of $a_\mu$ and in determining several of the systematic uncertainties in the calorimeter-based $\omega_a$ analysis. A detailed study of the impact of the internal alignment of the tracker, the $t_0$ and pileup on the determination of the beam position was undertaken and propagated through to an uncertainty in the $\omega_a$ determination. These uncertainties were used in the Fermilab Muon g-2 experiment's recent publication in Phys. Rev. Lett.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Beam Dynamics Challenges in the Muon g-2 Experiment

The muon&s;s anomalous magnetic moment $a_{\mu}$ has hinted at physics beyond the standard model for nearly 20 years. The Muon $g-2$ experiment at Fermilab aims to measure $a_{\mu}$ to 140 parts per billion (ppb) precision. The 460 ppb result from its first data run (Run-1), released in 2021, agreed with the previous 2006 Brookhaven Muon $g-2$ result. The experimental average stands in tension with the standard model theory $a_{\mu}$ prediction by $4.2 \sigma$. The result of Run-2/3 data analysis is set be released in summer 2023, and will improve on the Run-1 precision by a factor of two. With the data collected in all six runs, the experiment is on track to produce a 140 ppb measurement of $a_{\mu}$. If the experiment and theory central values are both unchanged, the tension would exceed $5 \sigma$. The measurement is accomplished by injecting muons into a magnetic storage ring and precisely measuring two observable frequencies: $\omega_a$, the muons&s; anomalous precession frequency, and $\tilde{\omega}&s;_p$, the precession frequency of protons which determines the magnetic field strength experienced by the muons. This thesis presents a selection of muon beam dynamics effects which are critical for reaching the experiment precision goal. A system of detectors assists with the challenging beam injection into the storage ring, and a measurement of the injected beam provides input for simulating the stored beam dynamics. A new method is introduced to reduce a critical systemic caused by time dependence in the stored beam momentum, enabled by a detector which directly profiles the stored beam. Finally the analysis of $\tilde{\omega}&s;_p$, the muon-weighted magnetic field, for the Run-2/3 result is presented. Systematics of $\tilde{\omega}&s;_p$ due to beam effects are evaluated in detail, and shown to be sub-dominant.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS2010

Reducing Field Distortion in Magnetic Resonance Imaging

A concept for a magnetic resonance imaging (MRI) system that would utilize a relatively weak magnetic field provides for several design features that differ significantly from the corresponding features of conventional MRI systems. Notable among these features are a magnetic-field configuration that reduces (relative to the conventional configuration) distortion and blurring of the image, the use of a superconducting quantum interference device (SQUID) magnetometer as the detector, and an imaging procedure suited for the unconventional field configuration and sensor. In a typical application of MRI, a radio-frequency pulse is used to excite precession of the magnetic moments of protons in an applied magnetic field, and the decaying precession is detected for a short time following the pulse. The precession occurs at a resonance frequency proportional to the strengths of the magnetic field and the proton magnetic moment. The magnetic field is configured to vary with position in a known way; hence, by virtue of the aforesaid proportionality, the resonance frequency varies with position in a known way. In other words, position is encoded as resonance frequency. MRI using magnetic fields weaker than those of conventional MRI offers several advantages, including cheaper and smaller equipment, greater compatibility with metallic objects, and higher image quality because of low susceptibility distortion and enhanced spin-lattice-relaxation- time contrast. SQUID MRI is being developed into a practical MRI method for applied magnetic flux densities of the order of only 100 T

Eom, Byeong Ho↗
DOE OSTI2017

The Calibration System of the E989 Experiment at Fermilab

The muon anomaly aµ is one of the most precise quantity known in physics experimentally and theoretically. The high level of accuracy permits to use the measurement of aµ as a test of the Standard Model comparing with the theoretical calculation. After the impressive result obtained at Brookhaven National Laboratory in 2001 with a total accuracy of 0.54 ppm, a new experiment E989 is under construction at Fermilab, motivated by the diff of aexp SM µ − aµ ∼ 3σ. The purpose of the E989 experiment is a fourfold reduction of the error, with a goal of 0.14 ppm, improving both the systematic and statistical uncertainty. With the use of the Fermilab beam complex a statistic of × 21 with respect to BNL will be reached in almost 2 years of data taking improving the statistical uncertainty to 0.1 ppm. Improvement on the systematic error involves the measurement technique of ωa and ωp, the anomalous precession frequency of the muon and the Larmor precession frequency of the proton respectively. The measurement of ωp involves the magnetic field measurement and improvements on this sector related to the uniformity of the field should reduce the systematic uncertainty with respect to BNL from 170 ppb to 70 ppb. A reduction from 180 ppb to 70 ppb is also required for the measurement of ωa; new DAQ, a faster electronics and new detectors and calibration system will be implemented with respect to E821 to reach this goal. In particular the laser calibration system will reduce the systematic error due to gain fl of the photodetectors from 0.12 to 0.02 ppm. The 0.02 ppm limit on systematic requires a system with a stability of 10−4 on short time scale (700 µs) while on longer time scale the stability is at the percent level. The 10−4 stability level required is almost an order of magnitude better than the existing laser calibration system in particle physics, making the calibration system a very challenging item. In addition to the high level of stability a particular environment, due to the presence of a 14 m diameter storage ring, a highly uniform magnetic field and the detector distribution around the storage ring, set specific guidelines and constraints. This thesis will focus on the final design of the Laser Calibration System developed for the E989 experiment. Chapter 1 introduces the subject of the anomalous magnetic moment of the muon; chapter 2 presents previous measurement of g-2, while chapter 3 discusses the Standard Model prediction and possible new physics scenario. Chapter 4 describes the E989 experiment. In this chapter will be described the experimental technique and also will be presented the experimental apparatus focusing on the improvements necessary to reduce the statistical and systematic errors. The main item of the thesis is discussed in the last two chapters: chapter 5 is focused on the Laser Calibration system while chapter 6 describes the Test Beam performed at the Beam Test Facility of Laboratori Nazionali di Frascati from the 29th February to the 7th March as a final test for the full calibrations system. An introduction explain the physics motivation of the system and the diff t devices implemented. In the final chapter the setup used will be described and some of the results obtained will be presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2016

Investigating the effect of zirconium oxide microstructure on corrosion performance: a comparison between neutron, proton, and nonirradiated oxides - 2016-0069

Scanning precession electron diffraction in the transmission electron microscope has been used to simultaneously map the phase, orientation, and grain morphology of oxides formed on Zircaloy-2 after three and six cycles in a boiling water reactor in unprecedented detail. For comparison, a region of a preoxidized autoclave-formed oxide was also proton-irradiated at the Dalton Cumbrian Facility. The proton irradiation was observed to cause additional stabilization of the tetragonal phase that was attributed to the stabilizing effect of irradiation- induced defects in the oxide. In the reactor-formed oxides, no extra stabilization of the tetragonal grains was observed under neutron irradiation, as indicated by the similar tetragonal phase fraction and transformation twin-boundary distributions between the nonirradiated and reactor-formed oxides. It is suggested that the damage rate is too low in the newly formed oxide to cause significant stabilization of the tetragonal phase. This technique also reveals that the oxide formed under reactor conditions has a more heterogeneous microstructure, and the growth of well-oriented columnar monoclinic grains is significantly reduced compared with a nonirradiated oxide. High-angle annular dark-field scanning transmission electron microscopy also revealed the development of extensive networks of intergranular porosity and eventually grain de-cohesion in the reactor-formed oxides. These results suggest that the tetragonal-monoclinic transformation is not responsible for the accelerated corrosion exhibited under reactor conditions. It is proposed that the usual out-of-reactor oxide growth and nucleation processes are significantly modified under reactor conditions, resulting in a more heterogeneous and randomly oriented oxide microstructure with reduced columnar grain growth. It is suggested that this disordered oxide microstructure allows for the formation of extensive intergranular porosity that could lead to accelerated in-reactor corrosion. (authors)

36 MATERIALS SCIENCE↗
DOE OSTI2025

Snakes for the Hadron Storage Ring

The Electron Ion Collider calls for collisions of polarized proton and polarized helion beams on polarized electron beams. To preserve polarization of these polarized hadron beams during acceleration, six full helical snakes will be installed. As there are currently 4 snakes in RHIC, the remaining two snakes will be made from existing rotator magnet coils. The existing snakes are made from only right-handed helices where the rotator magnets are made from both right handed and left handed helicity magnets. In order for a sufficient stock of spare coils, one snake will be made of left handed coils. Simulations using Opera field maps in zgoubi show the left handed snake has sufficient range to provide the desired snake precession axes for helions and protons with the existing power supplies. This is an overview of the right and left handed snake assemblies and their effects.

43 PARTICLE ACCELERATORS↗
DOE OSTI2025

Measurement of the positive muon anomalous magnetic moment to 127 ppb

A new measurement of the magnetic anomaly $a_μ$ of the positive muon is presented based on data taken from 2020 to 2023 by the Muon $g-2$ Experiment at Fermi National Accelerator Laboratory (FNAL). This dataset contains over 2.5 times the total statistics of our previous results. From the ratio of the precession frequencies for muons and protons in our storage ring magnetic field, together with precisely known ratios of fundamental constants, we determine $a_μ = 116\,592\,0710(162) \times 10^{-12}$ (139 ppb) for the new datasets, and $a_μ = 116\,592\,0705(148) \times 10^{-12}$ (127 ppb) when combined with our previous results. The new experimental world average, dominated by the measurements at FNAL, is $a_μ(\text{exp}) =116\,592\,0715(145) \times 10^{-12}$ (124 ppb). The measurements at FNAL have improved the precision on the world average by over a factor of four.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Measurement of the Spin Tune Using the Coherent Spin Motion of Polarized Protons in a Storage Ring

This Letter reports the first spin tune measurement at high energies (24 and 255 GeV) with a driven coherent spin motion. To maintain polarization in a polarized proton collider, it is essential to know the spin tune of the polarized proton beam, which is defined as the number of full spin precessions per revolution. A nine-magnet spin flipper has demonstrated high spin-flip efficiency in the presence of two Siberian snakes. The spin flipper drives a spin resonance with a given frequency (or tune) and strength. When the drive tune is close to the spin tune, the proton spin direction is not vertical anymore, but precesses around the vertical direction. By calculating the precession frequency of the horizontal component, the spin tune can be precisely measured. A driven coherent spin motion and fast turn-by-turn polarization measurement are keys to the measurement. The vertical spin direction is restored after turning the spin flipper off and the polarization value is not affected by the measurement. In conclusion, the fact that this manipulation preserves the polarization makes it possible to measure the spin tune during the operation of a high energy accelerator.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Electric dipole moments in 5+3 flavor weak effective theory

A fully generic treatment of electric dipole moments (EDMs) is presented in the CP-violating and flavor-conserving weak effective field theory (WET) with five flavors of quarks and three flavors of leptons. We systematically analyze leading contributions to EDMs originating from QCD and QED renormalization group running between the electroweak scale and low energy scales of about 2 GeV. We include the full one-loop anomalous dimension and a subset of two-loop corrections, as well as threshold corrections at the bottom, charm and τ masses. This allows us to derive master formulae in the space of generic WET for the neutron and proton EDMs, for EDMs of diamagnetic atoms, and for the precession frequencies constrained in molecular EDM experiments, from which bounds on the electron EDM are extracted. In particular, our master formulae capture the contributions of WET CP-violating operators with heavy quark and lepton flavors. As an application, we study EDM constraints on the Yukawa couplings of the Higgs boson, in both the linear and non-linear realizations of electroweak symmetry breaking.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

High Precision Magnetic Field Measurement for the Muon g-2 Experiment

The Muon g-2 experiment at Fermilab will measure the anomalous magnetic moment of the muon, aµ with a precision of 140 ppb, a four-fold improvement over the former BNL E821 result. If the current discrepancy of about 3.5σ between the Standard Model value for aµ and the former experiments was real, then the new experiment would verify the deviation with >7σ significance. The experiment uses muons with the magic momentum of 3.09 GeV/c stored in a very homogeneous magnetic field of a 45 m long storage ring. The determination of aµ requires the precise knowledge of both the anomalous muon spin precession, ωa, and the magnetic field, ωp, expressed in terms of the free-proton Larmor frequency. The field measurement uses the high precision tool of pulsed Nuclear Magnetic Resonance (pNMR) and requires cross-calibrating a set of probes: a very accurate NMR probe calibrates the 17 probes on the in-vacuum field mapping system (the so-called trolley). This trolley in turn is used to map the field over the full azimuth of the storage ring. The trolley measurement also provides the calibration of the 378 fixed probes around the ring that constantly monitor the field drift. This article presents the summary of the entire field measurement system needed to determine ωp. This work was supported in part by the US DOE, Fermilab and US DOE OHEP under contract No. KA2201020.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2014

nEDM at SNS

This PowerPoint presentation covered the following topics: Overview; participants in the collaboration; the experimental method and Free Precession Method descriptions; and then experimental design elements, ending with a summary. A new nEDM experiment is under development with a goal sensitivity 90% CL σ d < (3-5) x 10 -28 e-cm in 300 live-days; Free precession method: SQUIDS to read out the 3 He precession frequency, Scintillation signal for the n relative precession frequency; Dressed spin method: Strong RF field to match n and 3 He effective magnetic moments; Modulation/feedback of dressing parameter based on scintillation signal; and, Ongoing development/demonstration of many aspects of the apparatus (a subset was shown here).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗