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At least 1,675 records · Page 93

Calendar Year 2013 Annual Site Environmental Report for Sandia National Laboratories, Albuquerque, New Mexico

Sandia National Laboratories, New Mexico is a government-owned/contractor-operated facility. Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, manages and operates the laboratory for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA, Sandia Field Office administers the contract and oversees contractor operations at the site. This annual report summarizes data and the compliance status of Sandia Corporation’s sustainability, environmental protection, and monitoring programs through December 31, 2013. Major environmental programs include air quality, water quality, groundwater protection, terrestrial surveillance, waste management, pollution prevention, environmental restoration, oil and chemical spill prevention, and implementation of the National Environmental Policy Act. Environmental monitoring and surveillance programs are required by DOE Order 231.1B, Environment, Safety, and Health Reporting (DOE 2012).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

2015 Annual Site Environmental Report for Sandia National Laboratories New Mexico

Sandia National Laboratories, New Mexico, is a government-owned/contractor-operated facility. Sandia Corporation (Sandia), a wholly owned subsidiary of Lockheed Martin Corporation, manages and operates the Laboratories for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at the site. This Annual Site Environmental Report (ASER) summarizes data and the compliance status of Sandia's sustainability, environmental protection, and monitoring programs during calendar year 2015. Major environmental programs include air quality, water quality, groundwater protection, terrestrial surveillance, waste management, pollution prevention, environmental restoration, oil and chemical spill prevention, and implementation of the National Environmental Policy Act.

54 ENVIRONMENTAL SCIENCES↗

Simple concentration-dependent pair interaction model for large-scale simulations of Fe-Cr alloys

This work is motivated by the need for large-scale simulations to extract physical information on the iron-chromium system that is a binary model alloy for ferritic steels used or proposed in many nuclear applications. From first-principles calculations and the experimental critical temperature we build a new energetic rigid lattice model based on pair interactions with concentration and temperature dependence. Density functional theory calculations in both norm-conserving and projector augmented-wave approaches have been performed. A thorough comparison of these two different ab initio techniques leads to a robust parametrization of the Fe-Cr Hamiltonian. Mean-field approximations and Monte Carlo calculations are then used to account for temperature effects. The predictions of the model are in agreement with the most recent phase diagram at all temperatures and compositions. The solubility of Cr in Fe below 700 K remains in the range of about 6 to 12%. It reproduces the transition between the ordering and demixing tendency and the spinodal decomposition limits are also in agreement with the values given in the literature.

36 MATERIALS SCIENCE↗

Role of Well Operations and Multiphase Geomechanics in Controlling Fault Stability During CO 2 Storage and Enhanced Oil Recovery

CO 2 injection in active oil fields is a technology proposed for industrializing carbon storage operations. However, monitoring CO 2 migration, oil recovery, and mechanical deformation within caprock and on faults is a challenging problem in large-scale storage-enhanced oil recovery operations due to intersecting faults, multiphase flow effects, and wells with complex production-injection schedule. We develop and demonstrate a methodology based on our coupled modeling framework to monitor the movement of CO 2 , hydrocarbons and water, and the associated evolution in mechanical stability of faults during CO 2 storage-enhanced oil recovery in the Farnsworth Unit oil field in Texas, United States. The methodology honors geological, geophysical, and production-injection data acquired in the field over six decades. Differential depletion from hydraulically isolated fault compartments followed by water and CO 2 injection-induced overpressure causes volumetric contraction and expansion of the reservoir, and changes in the total and effective stresses in the overburden-reservoir-underburden complex. CO 2 migrates upward to accumulate near top of the geologic structure, and water migrates downward to pressurize the faults. Three-dimensional changes in the pressure and stress fields in the system lead to changes in the shear and effective normal tractions on three major faults compartmentalizing the field. Evolution in fault tractions is used to compute the evolution in the Coulomb failure function of the faults to quantify induced-slip tendency under production and injection. We explain the spatial heterogeneity and time variability of Coulomb failure function in terms of well location heterogeneity and well rate variability.

58 GEOSCIENCES↗

Dynamical Invariants and Robertson-Schroedinger Correlated States of Electromagnetic Field in Nonstationary Linear Media

Dynamical invariants and statistical properties of the quantized electromagnetic field in nonstationary linear media (dielectric and/or conductive) are considered in the framework of Choi-Yeon quantization scheme. It is shown that in the eigenstates of linear dynamical invariant the Robertson-Schroedinger uncertainty relation is minimized, both for the photon annihilation operator quadratures and for the electric and magnetic field components. The time evolution of initial Glauber coherent states and Fock (photon number) states is considered. On an initial coherent state the medium conductivity and the time-dependent electric permeability both are shown to act as squeezing and correlating factors.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Determination of the chiral condensate from QCD Dirac spectrum on the lattice

We calculate the chiral condensate of QCD with 2, 2+1, and 3 flavors of sea quarks. Lattice QCD simulations are performed employing dynamical overlap fermions with up- and down-quark masses covering a range between 3 and 100 MeV. On L{approx}1.8-1.9 fm lattices at a lattice spacing {approx}0.11 fm, we calculate the eigenvalue spectrum of the overlap-Dirac operator. By matching the lattice data with the analytical prediction from chiral perturbation theory at the next-to-leading order, the chiral condensate in the massless limit of up and down quarks is determined.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

A Kirkpatrick-Baez microscope for the National Ignition Facility

Current pinhole x ray imaging at the National Ignition Facility (NIF) is limited in resolution and signal throughput to the detector for Inertial Confinement Fusion applications, due to the viable range of pinhole sizes (10–25 μm) that can be deployed. A higher resolution and throughput diagnostic is in development using a Kirkpatrick-Baez microscope system (KBM). The system will achieve <9 μm resolution over a 300 μm field of view with a multilayer coating operating at 10.2 keV. Presented here are the first images from the uncoated NIF KBM configuration demonstrating high resolution has been achieved across the full 300 μm field of view.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Relativistic equations with fractional and pseudodifferential operators

In this paper we use different techniques from the fractional and pseudo-operators calculus to solve partial differential equations involving operators with noninteger exponents. We apply the method to equations resembling generalizations of the heat equations and discuss the possibility of extending the procedure to the relativistic Schroedinger and Dirac equations.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Nuclear-Level Effective Theory of 𝜇 → 𝑒 Conversion

The Mu2e and COMET 𝜇 → 𝑒 conversion experiments are expected to significantly advance limits on new sources of charged lepton flavor violation. Almost all theoretical work in the field has focused on just two operators. However, general symmetry arguments lead to a 𝜇 → 𝑒 conversion rate with six response functions, each of which, in principle, is observable by varying nuclear properties of targets. We construct a nucleon-level nonrelativistic effective theory (NRET) to clarify the microscopic origin of these response functions and to relate rate measurements in different targets. This exercise identifies three operators and their small parameters that control the NRET operator expansion. We note inconsistencies in past treatments of these parameters. The NRET is technically challenging, involving 16 operators, several distorted electron partial waves, bound muon upper and lower components, and an exclusive nuclear matrix element. We introduce a trick for treating the electron Coulomb effects accurately, which enables us to include all of these effects while producing transition densities whose one-body matrix elements can be evaluated analytically, greatly simplifying the nuclear physics. We derive bounds on operator coefficients from existing and anticipated 𝜇 → 𝑒 conversion experiments. We discuss how similar NRET formulations have impacted dark matter phenomenology, noting that the tools this community has developed could be adapted for charged lepton flavor violation studies.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Operating single quantum emitters with a compact Stirling cryocooler

The development of an easy-to-operate light source emitting single photons has become a major driving force in the emerging field of quantum information technology. Here, we report on the application of a compact and user-friendly Stirling cryocooler in the field of nanophotonics. The Stirling cryocooler is used to operate a single quantum emitter constituted of a semiconductor quantum dot (QD) at a base temperature below 30 K. Proper vibration decoupling of the cryocooler and its surrounding enables free-space micro-photoluminescence spectroscopy to identify and analyze different charge-carrier states within a single quantum dot. As an exemplary application in quantum optics, we perform a Hanbury-Brown and Twiss experiment demonstrating a strong suppression of multi-photon emission events with g{sup (2)}(0) < 0.04 from this Stirling-cooled single quantum emitter under continuous wave excitation. Comparative experiments performed on the same quantum dot in a liquid helium (LHe)-flow cryostat show almost identical values of g{sup (2)}(0) for both configurations at a given temperature. The results of this proof of principle experiment demonstrate that low-vibration Stirling cryocoolers that have so far been considered exotic to the field of nanophotonics are an attractive alternative to expensive closed-cycle cryostats or LHe-flow cryostats, which could pave the way for the development of high-quality table-top non-classical light sources.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

2016 Annual Site Environmental report Sandia National Laboratories Tonopah Test Range Nevada & Kaua'i Test Facility Hawai'i.

Sandia National Laboratories (SNL) is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s (DOE’s), National Nuclear Security Administration (NNSA) under contract DE-NA0003525. The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at the SNL, Tonopah Test Range (SNL/TTR) in Nevada and the SNL, Kaua‘i Test Facility (SNL/KTF) in Hawai‘i. SNL personnel manage and conduct operations at SNL/TTR in support of the DOE/NNSA’s Weapons Ordnance Program and have operated the site since 1957. Navarro Research and Engineering personnel perform most of the environmental programs activities at SNL/TTR. The DOE/NNSA/Nevada Field Office retains responsibility for cleanup and management of SNL/TTR Environmental Restoration sites. SNL personnel operate SNL/KTF as a rocket preparation launching and tracking facility. This Annual Site Environmental Report (ASER) summarizes data and the compliance status of sustainability, environmental protection, and monitoring programs at SNL/TTR and SNL/KTF during calendar year 2016. Major environmental programs include air quality, water quality, groundwater protection, terrestrial and biological surveillance, waste management, pollution prevention, environmental restoration, oil and chemical spill prevention, and implementation of the National Environmental Policy Act. This ASER is prepared in accordance with and as required by DOE O 231.1B, Admin Change 1, Environment, Safety, and Health Reporting.

54 ENVIRONMENTAL SCIENCES↗

Performance and Health Test Procedure for Grid Energy Storage Systems

A test procedure to evaluate the performance and health of field installations of grid-connected battery energy storage systems (BESS) is described. Performance and health metrics captured in the procedures are: round-trip efficiency, standby losses, response time/accuracy, and useable energy/state of charge at different discharge/charge rates over the system's lifetime. The procedures are divided into reference performance tests, which require the system to be put in a test mode and are to be conducted in intervals, and real-time monitoring tests, which collect data during normal operation without interruption. The procedures can be applied on a wide array of BESS with little modification and can thus support BESS operators in the management of BESS field installations with minimal interruption and expenditure. Simulated results based on a detailed system simulation of a prototype system are provided as guideline.

25 ENERGY STORAGE↗

The Oak Ridge Isochronous Cyclotron Refurbishment Project

The Oak Ridge Isochronous Cyclotron (ORIC) has been in operation for nearly fifty years at the Oak Ridge National Laboratory (ORNL). Presently, it serves as the driver accelerator for the ORNL Holifield Radioactive Ion Beam Facility (HRIBF), where radioactive ion beams are produced using the Isotope Separation Online (ISOL) technique for post-acceleration by the 25URC tandem electrostatic accelerator. Operability and reliability of ORIC are critical issues for the success of HRIBF and have presented increasingly difficult operational challenges for the facility in recent years. In February 2010, a trim coil failure rendered ORIC inoperable for several months. This presented HRIBF with the opportunity to undertake various repairs and maintenance upgrades aimed at restoring the full functionality of ORIC and improving the reliability to a level better than what had been typical over the previous decade. In this paper, we present details of these efforts, including the replacement of the entire trim coil set and measurements of their radial field profile. Comparison of measurements and operating tune parameters with setup code predictions will also be presented.

Ball, James B↗

Microscopic description of large-amplitude shape-mixing dynamics with local QRPA inertial functions

We introduce a microscopic approach to derive all the inertial functions in the five-dimensional quadrupole collective Hamiltonian. Local normal modes are evaluated on the constrained mean field in the quasiparticle random-phase approximation in order to derive the inertial functions. The collective Hamiltonians for neutron-rich Mg isotopes are determined with use of this approach, and the shape coexistence/mixing around the N = 20 region is analyzed.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing

This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e⁺/e⁻ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.

43 PARTICLE ACCELERATORS↗

Microscopic description of large-amplitude shape-mixing dynamics with inertial functions derived in local quasiparticle random-phase approximation

On the basis of the adiabatic self-consistent collective coordinate method, we develop an efficient microscopic method of deriving the five-dimensional quadrupole collective Hamiltonian and illustrate its usefulness by applying it to the oblate-prolate shape coexistence/mixing phenomena in proton-rich {sup 68,70,72}Se. In this method, the vibrational and rotational collective masses (inertial functions) are determined by local normal modes built on constrained Hartree-Fock-Bogoliubov states. Numerical calculations are carried out using the pairing-plus-quadrupole Hamiltonian including the quadrupole-pairing interaction within the two major-shell active model spaces both for neutrons and protons. It is shown that the time-odd components of the moving mean-field significantly increase the vibrational and rotational collective masses in comparison with the Inglis-Belyaev cranking masses. Solving the collective Schroedinger equation, we evaluate excitation spectra, quadrupole transitions, and moments. The results of the numerical calculation are in excellent agreement with recent experimental data and indicate that the low-lying states of these nuclei are characterized as an intermediate situation between the oblate-prolate shape coexistence and the so-called {gamma} unstable situation where large-amplitude triaxial-shape fluctuations play a dominant role.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗