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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 OSTI2019

Long-Term Stewardship Optimization for a Decommissioned Nuclear Reactor - 19579

The decommissioned Hallam Nuclear Power Facility (Hallam), located in Lancaster County, Nebraska, approximately 19 miles south of Lincoln, was developed as a prototype to investigate the technical and economic feasibility of a sodium-cooled, graphite-moderated nuclear reactor. As part of its Power Demonstration Program, the US Atomic Energy Commission (US AEC), a predecessor agency of the US Department of Energy (US DOE), operated the Hallam reactor from 1962 to 1964. The radiological surveillance of the Hallam site was established when the operating agreement between AEC and the Nebraska Public Power District was terminated. The US DOE Chicago Operations Office and the Nebraska Department of Health (NDH) agreed to install a shallow groundwater monitoring system as part of the environmental surveillance program. Surveillance at the site was scheduled to end in fiscal year 2005, with no further activities planned after that. At that time, the plan was to transition the site to the Nebraska Public Power District with future use of the facility to remain restricted. US DOE has title to and responsibility for the entombed radioactive materials. A surveillance and monitoring program was initiated in 1970 by NDH and was funded by US AEC. It included the analysis of samples from deep production wells (groundwater from the regional aquifer at depths greater than 55 meters [180 feet]) at the Sheldon Station. NDH was concerned in 1990 about the possibility of shallow groundwater coming in contact with the buried radiological materials along the buried walls of the reactor. Subsequently, DOE and NDH agreed to further characterize hydrologic conditions and establish a monitoring program in the shallow, perched groundwater zones. The current monitoring program focuses on the shallow, perched groundwater. Today, decades since facility decommissioning, site inspections and groundwater monitoring continue at this Cold War-era legacy site. The US DOE Office of Legacy Management (LM) monitors groundwater as a best management practice in response to a request from the Nebraska Department of Health and Human Services (DHHS). In 2006, LM recommended discontinuing groundwater monitoring because analytical results since 1970 demonstrated there had been no impact to shallow, perched groundwater and no current or anticipated unacceptable risk to human health and the environment. The State of Nebraska did not concur with the recommendation to stop monitoring but did agree to a reduction in sampling and analysis from once a year to once every 2 years--a schedule that began in 2008. An updated assessment of the groundwater monitoring effort was issued in 2016. The entire body of water-quality data continues to demonstrate that there have been no negative impacts to the shallow, perched groundwater from radioactive materials entombed at the site 46 years ago. LM, with concurrence from Nebraska DHHS, changed the sampling frequency, effective in 2018, as follows: once every 5 years from 2021 to 2041 and once every 10 years from 2041 to 2071. In summary, LM remains committed to its primary mission to protect human health and the environment at each of its 92 legacy sites. With results from groundwater sampling events demonstrating compliance for 48 years, the Hallam site was able to set an LM benchmark to optimize long-term stewardship and define an end-state strategy for other decommissioned reactor facilities across the DOE complex. Continued collaboration with local communities, stakeholder, and regulators often leads to outcomes of sound protectiveness without compromise to safety or compliance, as demonstrated by the optimization of the long-term stewardship at the Hallam site. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2010

Spin physics at RHIC

Polarized-proton collisions at a collision energy 200 GeV started in 2001 at RHIC in BNL. We have investigated a polarized structure of the proton to understand the origin of the nucleon spin 1/2 with polarized-proton collisions. The first goal of spin physics at RHIC is determination of the gluon-spin contribution to the proton spin. The PHENIX and STAR experiments have investigated the gluon-spin contribution by measuring longitudinal-spin asymmetries of neutral pion and jet produced in longitudinally-polarized proton collisions. Experimental results have shown that these asymmetries are small and strong constraints have been given for the gluon-spin contribution. From 2009, polarized-proton collisions at a collision energy 500 GeV started and we have investigated flavor-sorted contribution of the quark spin to the proton spin with weak-boson production. The final remaining piece of information to understand the proton spin is orbital-angular momenta of quarks and gluons. Multi-dimensional structure of the nucleon which includes information of the orbital-angular motion inside the nucleon has been investigated with transverse-spin asymmetry measurements.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2010

Experimental Studies of Quark Gluon Plasma at RHIC

A new state of matter, Quark Gluon Plasma (QGP) is supposed to exist under extreme temperature and/or density conditions just as a beginning of this early universe after the Big Bang. High energy nucleus-nucleus collisions at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) has been used to form the QGP and to study the properties of QGP. The recent progress on the experimental research of QGP at RHIC experiments and the understanding of the properties are discussed. Major discoveries at RHIC experiments are very strong energy loss of high energy partons in central Au+Au collisions and very large elliptic and collective expansion given by the initial almond geometry in non-central Au+Au collisions. Those two finding and related physics explanations as well as future plans are presented.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2010

Physics of Hot Partonic Matter at LHC-ALICE

The field of high energy nuclear physics has recently reached epoch making discoveries at the Relativistic Heavy Ton Collider at Brookhaven National Laboratory, highlighted with that of new state of nuclear matter with partonic degrees of freedom. The ALICE experiment at the Large Hadron Collider at CERN aims at comprehensive investigation and understanding of properties of the hot and dense partonic matter, as the only experiment dedicated to nucleus-nucleus collisions at the facility. Physics prospects at ALICE are reviewed including jet quenching as a probe of energy loss of quarks in the created medium, direct and thermal photons as vital probes of the thermal properties, and quarkonia as a beloved probe of color deconfinement, along with latest status of the detector systems including the high resolution electromagnetic calorimeter, PHOS, and a quick report from the first operation of LHC and ALICE in December, 2009.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2010

A Renewal Plan for the Advanced Photon Source

With coordination from the APS Renewal Steering Committee (the members of which are the co-authors of this paper), staff and users of the U.S. Department of Energy's Advanced Photon Source (APS) at Argonne National Laboratory are in the process of developing a renewal plan for the facility. The renewal is a coordinated upgrade of the accelerator, beamlines, and associated technical structure that will enable users of the APS to address key scientific challenges in the coming decades. The cost of the renewal is estimated to be from $300M to $400M and to take approximately six years from start to finish.

43 PARTICLE ACCELERATORS↗
DOE OSTI2010

X-ray phase-contrast imaging with an Inverse Compton Scattering source

Single-shot in-line phase-contrast imaging with the Inverse Compton Scattering X-ray source available at ATF (Accelerator Test Facility) at Brookhaven National Laboratory is experimentally demonstrated. Phase-contrast images of polymer wires are obtained with a single X-ray pulse whose time length is about 1 picosecond. The edge-enhancement effect is clearly visible in the images and simulations show a quantitative agreement with experimental data. A phase-retrieval step in the image processing leads to a accurate estimation of the projected thickness of our samples. Finally, a single-shot image of a wasp is presented as an example of a biological sample.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2010

Periodicities in Nuclear Decay Data: Systematic Effects or New Physics?

Recent comparisons of independent and unrelated nuclear decay experiments have shown unexplained oscillations that appear to be common in frequency and phase. The most logical explanation for this fluctuation would be some common systematic or environmental factor. In this paper we provide detailed spectral analysis comparisons of several environmental factors with nuclear decay data from an experiment performed at the Brookhaven National Laboratory. We demonstrate that, although none of the environmental factors investigated can be causal, comparisons with ACRIM solar irradiance measurements provide good agreement with the nuclear decay data. This analysis provides the first direct evidence that the cause of the fluctuations has a possible solar origin.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2010

ORNL Radioactive Beams for Stellar Explosion Studies

At ORNL, we are using unique radioactive beams to measure scattering, transfer, and capture reactions to help understand exploding stars such as novae, supernovae, and X-ray bursts. Recent results have been obtained with beams of {sup 26}Al, {sup 17}F, and {sup 130,132}Sn, utilizing gas targets, silicon strip detectors, and recoil separators. More exciting work is planned at the future FRIB facility. We are also using synergistic nuclear data evaluations and the Computational Infrastructure for Nuclear Astrophysics to investigate the astrophysical impact of our measurements.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2010

High Frequency, High Gradient Dielectric Wakefield Acceleration Experiments at SLAC and BNL

Given the recent success of >GV/m dielectric wakefield accelerator (DWA) breakdown experiments at SLAC, and follow-on coherent Cerenkov radiation (CCR) production at the UCLA Neptune, a UCLA-USC-SLAC collaboration is now implementing a new set of experiments that explore various DWA scenarios. These experiments are motivated by the opportunities presented by the approval of the FACET facility at SLAC, as well as unique pulse-train wakefield drivers at BNL. The SLAC experiments permit further exploration of the multi-GeV/m envelope in DWAs, and will entail investigations of novel materials (e.g. CVD diamond) and geometries (Bragg cylindrical structures, slab-symmetric DWAs), and have an over-riding goal of demonstrating >GeV acceleration in {approx}33 cm DWA tubes. In the nearer term before FACET's commissioning, we are performing measurements at the BNL ATF, in which we drive {approx}50-200 MV/m fields with single pulses or pulse trains, and observe resonantly driven CCR as well as deflection modes. These experiments are of high relevance to enhancing linear collider DWA designs, as they will demonstrate potential for high efficiency operation with pulse trains, and explore transverse modes for the first time.

43 PARTICLE ACCELERATORS↗
DOE OSTI2010

Resonant Excitation of Plasma Wakefields

We describe characteristics of the bunch train and plasma source used in a resonant plasma wakefield experiment at the Brookhaven National Laboratory Accelerator Test Facility. The bunch train has the proper correlated spread to unambiguously observe the expected energy gain by the witness bunch at resonance. The plasma density in the capillary discharge is sufficiently high to reach the resonance with the typical bunch train spacing of this experiment. It is also uniform over more than 3/4 of the 2 cm-long capillary.

43 PARTICLE ACCELERATORS↗
DOE OSTI2010

Optical Frequency Domain Visualization of Electron Beam Driven Plasma Wakefields

Bunch driven plasma wakefield accelerators (PWFA), such as the 'plasma afterburner', are a promising emerging method for significantly increasing the energy output of conventional particle accelerators. The study and optimization of this method would benefit from an experimental correlation of the drive bunch parameters and the accelerated particle parameters with the corresponding plasma wave structure. However, the plasma wave structure has not been observed directly so far. We will report ongoing development of a noninvasive optical Frequency Domain Interferometric (FDI) and Holographic (FDH) diagnostics of bunch driven plasma wakes. Both FDI and FDH have been previously demonstrated in the case of laser driven wakes. These techniques employ two laser pulses co-propagating with the drive particle bunch and the trailing plasma wave. One pulse propagates ahead of the drive bunch and serves as a reference, while the second is overlapped with the plasma wave and probes its structure. The multi-shot FDI and single-shot FDH diagnostics permit direct noninvasive observation of longitudinal and transverse structure of the plasma wakes. The experiment is being developed at the 70 MeV Linac in the Accelerator Test Facility at Brookhaven National Laboratory to visualize wakes generated by two and multi-bunch drive beams.

43 PARTICLE ACCELERATORS↗
DOE OSTI2010

Simulation of Current Filamentation Instability for an Accelerator Beam in a Capillary Plasma

Current Filamentation Instability (CFI) is of central importance for the propagation of relativistic electron beams in plasmas. It could play an important role in the generation of magnetic fields and of radiation in the after-glow of gamma ray bursts as well as in hot electrons energy transport in the fast-igniter inertial confinement fusion concept. Using the particle-in-cell code QuickPIC, simulations of the electron beam at the Brookhaven National Laboratory--Accelerator Test Facility, BNL-ATF, propagating in a cm-long plasma were conducted. Simulation results show that with beam and plasma parameters achievable at the BNL-ATF, the CFI should be observed within 2 cm of plasma. Simulation results are presented for an experiment currently underway at BNL-ATF and possible diagnostics for characterizing the instability are discussed.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

(g-2){sub {mu}} and {Delta}{alpha}: recent developments and status report

We briefly review the Standard Model prediction of g-2 and confront it with the formidably accurate measurement from BNL. The focus is on recent improvements of the hadronic vacuum polarisation contributions. We also calculate the running QED coupling at the scale of the Z boson mass, {alpha}(M{sub Z}{sup 2}), an important ingredient in electroweak precision fits.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

J/{psi} Production with NRQCD: HERA, Tevatron, RHIC and LHC

We report on our recent calculation of the inclusive direct photo- and hadroproduction of the J/{psi} meson at next-to-leading order within the factorization formalism of nonrelativistic QCD. We fit the color-octet (CO) long-distance matrix elements <O{sup J}/{psi}(1S{sub 0}{sup [8]})>, <O{sup J}/{psi}(3S{sub 1}{sup [8]})> and <O{sup J}/{psi}(3P{sub 0}{sup [8]})> to the transverse momentum (p{sub T}) distributions measured by CDF at Fermilab Tevatron and by H1 at DESY HERA and show that they also successfully describe the p{sub T} distributions from PHENIX at BNL RHIC and CMS at the CERN LHC as well as the photon-proton c.m. energy and (with worse agreement) the inelasticity distributions from H1. In all experiments, the CO processes are shown to be indispensable.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Radio-Purification of Neodymium Chloride

Organometallic liquid scintillator becomes one of the man detection mediums for neutrino experiment. Liquid-liquid extraction is the method of choice for loading metallic ions of interest into the organic solvents at BNL. High purity of all starting materials is essential for the optimization of synthesis. A newly developed 'self-scavenging' technique was applied to purify undesired radioisotopes from the starting metal compound and found to effectively remove thorium and such containments from the neodymium chloride for SNO+.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2011

Uniform Beam Distributions Of Charged Particle Beams

The use of octupole elements was originally suggested [1] to transform the transverse Gaussian distribution of a charged particle beam into a uniform beam distribution having rectangular cross section. The first experimental realization of this concept was materialized at the Radiation Effects Facility (REF) of the Brookhaven National Laboratory (BNL)[2] where the transverse Gaussian distribution of a 200 MeV H{sup -} beam was transformed into a rectangular uniform distribution. Later, the beam line of the NASA Space Radiation Laboratory (NSRL) facility [3,4] built at BNL, was specifically designed to generate uniform beam distributions with rectangular cross sections, in both, the horizontal and vertical directions, at the location of the target. The NSRL facility generates uniform beam distributions of various nuclear species, which may vary in energy, and also vary in size of the uniform beam distribution. We will present an overview of the method to generate uniform beam distributions, show some results from the NSRL facility, and suggest other possibilities for generating such beam distributions.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Exploring Low Energy Molecular Ion Reactions With Merged Beams

Charge transfer (CT) in molecular ion-neutral interactions can proceed through dynamically coupled electronic, vibrational, and rotational degrees of freedom. Using the upgraded Oak Ridge National Laboratory ion-atom merged-beams apparatus, absolute direct charge transfer is explored from keV/u collision energies where the collision is considered ''ro-vibrationally frozen'' to sub-eV/u collision energies where collision times are long enough to sample vibrational and rotational modes. Our first molecular ion measurement with the merged-beams apparatus has been performed for D{sub 2}{sup +}+H and is used to benchmark high energy sudden approximation theory and vibrational specific adiabatic theory for the (H{sub 2}-H){sup +} complex. CT measurements have also been performed for D{sub 3}{sup +}+H from 2 eV/u to 2 keV/u and CO{sup +}+D from 20 eV/u to 2000 eV/u. With straightforward improvements to the apparatus, we plan to extend our measurements to key ''destructive'' rate coefficients for H{sub 2}{sup +} and CH{sup +} with H at temperatures relevant to the interstellar medium.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2011

Solar Wind Charge Exchange Studies Of Highly Charged Ions On Atomic Hydrogen

Accurate studies of low-energy charge exchange (CX) are critical to understanding underlying soft X-ray radiation processes in the interaction of highly charged ions from the solar wind with the neutral atoms and molecules in the heliosphere, cometary comas, planetary atmospheres, interstellar winds, etc.. Particularly important are the CX cross sections for bare, H-like, and He-like ions of C, N, O and Ne, which are the dominant charge states for these heavier elements in the solar wind. Absolute total cross sections for single electron capture by H-like ions of C, N, O and fully-stripped O ions from atomic hydrogen have been measured in an expanded range of relative collision energies (5 eV/u-20 keV/u) and compared to previous H-oven measurements. The present measurements are performed using a merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source installed on a high voltage platform at the Oak Ridge National Laboratory. For the collision energy range of 0.3 keV/u-3.3 keV/u, which corresponds to typical ion velocities in the solar wind, the new measurements are in good agreement with previous H-oven measurements. The experimental results are discussed in detail and compared with theoretical calculations where available.

74 ATOMIC AND MOLECULAR PHYSICS↗