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At least 1,153 records · Page 64

Annual Status Report (FY2017): Performance Assessment for the Disposal of Low-Level Waste in the 200 West Area Burial Grounds

This annual review provides the projected dose estimates of radionuclide inventories disposed in the active 200 West Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-EP-06451). These estimates are compared with performance objectives defined in U.S. Department of Energy (DOE) requirements (DOE O 435.1 Chg 1 2 and its companion documents DOE M 435.1-1 Chg 1 3 and DOE G 435.1-1 4 ). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063 5 ) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations, which indicate potential impacts well below performance objectives. Therefore, future compliance with DOE O 435.1 Chg 1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Annual Status Report (FY2017): Performance Assessment for the Disposal of Low-Level Waste in the 200 East Area Burial Grounds

This annual review provides the projected dose estimates of radionuclide inventories disposed in the active 200 East Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. The estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-SD-WM-TI-7301). The estimates are compared with performance objectives defined in U.S. Department of Energy (DOE) requirements (DOE O 435.1 Chg 1, 2 and companion documents DOE M 435.1-1 Chg 1 3 and DOE G 435.1-1 4 ). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-00635) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations, which indicate potential impacts well below performance objectives. Therefore, future compliance with DOE O 435.1 Chg 1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Master equation approach for interacting slow- and stationary-light polaritons

A master equation approach for the description of dark-state polaritons in coherently driven atomic media is presented. This technique provides a description of light-matter interactions under conditions of electromagnetically induced transparency (EIT) that is well suited for the treatment of polariton losses. The master equation approach allows us to describe general polariton-polariton interactions that may be conservative, dissipative, or a mixture of both. In particular, it enables us to study dissipation-induced correlations as a means for the creation of strongly correlated polariton systems. Our technique reveals a loss mechanism for stationary-light polaritons that has not been discussed so far. We find that polariton losses in level configurations with nondegenerate ground states can be a multiple of those in level schemes with degenerate ground states.

74 ATOMIC AND MOLECULAR PHYSICS↗

Estimating the Noise Dose Range of the NASA X-59 Aircraft in Supersonic Cruise Using PCBoom Propagation Simulations

PCBoom propagation simulations of the NASA X-59 low-boom in supersonic cruise were conducted using near-field CFD pressure waveforms as inputs to estimate the noise dose range. Low-booms were propagated through realistic atmospheric profiles from the Climate Forecast System Version 2 across the USA, and loudness statistics of the low-booms are presented. The near-field waveforms correspond to aircraft configurations expected to produce minimum- and maximum-loudness levels on the ground. The simulations show that the practical Perceived Level noise dose range is 72 to 86.7 dB. Dose ranges for other single event and cumulative sonic boom metrics of interest are also provided.

X-59↗

GLM Proxy Data Generation: Methods for Stroke/Pulse Level Inter-Comparison of Ground-Based Lightning Reference Networks

In order to produce useful proxy data for the GOES-R Geostationary Lightning Mapper (GLM) in regions not covered by VLF lightning mapping systems, we intend to employ data produced by ground-based (regional or global) VLF/LF lightning detection networks. Before using these data in GLM Risk Reduction tasks, it is necessary to have a quantitative understanding of the performance of these networks, in terms of CG flash/stroke DE, cloud flash/pulse DE, location accuracy, and CLD/CG classification error. This information is being obtained through inter-comparison with LMAs and well-quantified VLF/LF lightning networks. One of our approaches is to compare "bulk" counting statistics on the spatial scale of convective cells, in order to both quantify relative performance and observe variations in cell-based temporal trends provided by each network. In addition, we are using microsecond-level stroke/pulse time correlation to facilitate detailed inter-comparisons at a more-fundamental level. The current development status of our ground-based inter-comparison and evaluation tools will be presented, and performance metrics will be discussed through a comparison of Vaisala s Global Lightning Dataset (GLD360) with the NLDN at locations within and outside the U.S.

Cummins, Kenneth L.↗

The optical pumping of alkali atoms using coherent radiation from semi-conductor injection lasers and incoherent radiation from resonance lamps

An experimental study for creating population differences in the ground states of alkali atoms (Cesium 133) is presented. Studies made on GaAs-junction lasers and the achievement of population inversions among the hyperfine levels in the ground state of Cs 133 by optically pumping it with radiation from a GaAs diode laser. Laser output was used to monitor the populations in the ground state hyperfine levels as well as to perform the hyperfine pumping. A GaAs laser operated at about 77 K was used to scan the 8521 A line of Cs 133. Experiments were performed both with neon-filled and with paraflint-coated cells containing the cesium vapor. Investigations were also made for the development of the triple resonance coherent pulse technique and for the detection of microwave induced hyperfine trasistions by destroying the phase relationships produced by a radio frequency pulse. A pulsed cesium resonance lamp developed, and the lamp showed clean and reproducible switching characteristics.

Singh, G.↗

Performance Assessment for the Disposal of Low Level Waste in the 200 East Area Burial Grounds (FY2019 Annual Status Report)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the 200 East Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-SD-WM-TI-730) and are compared with U.S. Department of Energy requirements (DOE O 435.1 and performance objectives defined in companion documents DOE M 435.1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations, indicating that potential impacts are well below performance objectives; therefore, future compliance with DOE O 435.1 is expected. A new PA study has been initiated in this fiscal year (FY) 2019 for evaluation of active disposal sites within the 200 West and East Areas (Trenches 31 and 34 in 200 West; Trench 94 in 200 East) because extended time has elapsed between the current annual status report and the original PA (WHC-SD-WM-TI-370) for the active disposal sites. The new PA for the active disposal sites is expected to be completed in FY 2021.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment for the Disposal of Low Level Waste in the 200 West Area Burial Grounds (FY2019 Annual Statius Report)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the active 200 West Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-EP-0645) and are compared with performance objectives defined in U.S. Department of Energy requirements (DOE O 435.1 and its companion documents DOE M 435.1-1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations, indicating that potential impacts are well below performance objectives; therefore, future compliance with DOE O 435.1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment for the Disposal of Low-Level Waste in the 200 East Area Burial Grounds (Annual Status Report FY 2022)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the 200 East Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-SD-WM-TI-730). The estimates are compared with the performance objectives defined in U.S. Department of Energy requirements (DOE O 435.1 and its companion documents DOE M 435.1-1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations that indicate potential impacts well below performance objectives; therefore, future compliance with DOE O 435.1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment for the Disposal of Low-Level Waste in the 200 East Area Burial Grounds (Annual Summary Report - FY 23)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the 200 East Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. All trenches in these burial grounds except one have remained inactive since 2005. Trench 94 located in 218-E-12B Burial Ground is the only active trench that is dedicated for disposal of U.S. Navy reactor compartments. During this reporting period (fiscal year 2023, from October 1, 2022, through September 30, 2023), no reactor compartments were disposed in Trench 94.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Resonance ionization of titanium: high useful yield and new autoionizing states

The isotopic composition of titanium in meteoritic phases can be used to decipher processes such as stellar nucleosynthesis and galactic chemical evolution. In order to facilitate analyses of trace amounts of titanium in atom-limited samples, here we established a new three-step resonance ionization scheme. The scheme was developed using titanium–sapphire lasers and we show that it can be easily saturated and that it yields stable isotope measurements. Using the LION (Laser Ionization Of Neutrals) instrument we demonstrate a useful yield of 10.1% ± 1.6% when ionizing from the ground state. We determined the population of two low-lying electronic states within the ground state multiplet and show that accessing all three levels of the ground state manifold would result in an overall useful yield of ~18%. The useful yield agrees well with expectations based on prior analyses of uranium using LION. In addition, we report the energy levels of nine new autoionizing states between 56 217 cm -1 and 57 086 cm -1 .

47 OTHER INSTRUMENTATION↗

Performance Assessment for the Disposal of Low-Level Waste in the 200 West Area Burial Grounds (Annual Status Report FY 2021)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the active 200 West Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-EP-0645). The estimates are compared with the performance objectives defined in U.S. Department of Energy requirements (DOE O 435.1 and its companion documents DOE M 435.1-1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063). and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations that indicate potential impacts well below performance objectives; therefore, future compliance with DOE O 435.1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Flying-qualities criteria for wings-level-turn maneuvering during an air-to-ground weapon delivery task

A moving base simulator experiment demonstrated that a wings-level-turn control mode improved flying qualities for air to ground weapon delivery compared with those of a conventionally controlled aircraft. Evaluations of criteria for dynamic response for this system have shown that pilot ratings correlate well on the basis of equivalent time constant of the initial response. Ranges of this time constant, as well as digital system transport delays and lateral acceleration control authorities that encompassed level 1 through 3 handling qualities, were determined.

Sammonds, R. I.↗

GPM Ground Validation at NASA Wallops Precipitation Research Facility

The Wallops Precipitation Research Facility (WPRF) at NASA Goddard Space Flight Center, Wallops Island, VA has been established as a semi-permanent super-site for the Global Precipitation Measurement (GPM) Ground Validation (GV) program. WPRF is home to research quality precipitation instruments, including NASA’s S-band dual-polarimetric radar (NPOL), and a network of profiling radars, disdrometers, and rain gauges. This study investigates the statistical agreement of the GPM Core Observatory Dual Frequency Precipitation Radar (DPR), combined DPR-GPM Microwave Imager (GMI) and GMI Level II precipitation retrievals compared to WPRF ground observations from a six-year collection of satellite overpasses. Multi-sensor observations are integrated using the System for Integrating Multiplatform Data to Build the Atmospheric Column (SIMBA) software package. SIMBA ensures measurements recorded in a variety of formats are synthesized into a common reference frame for ease in comparison and analysis. Given that instantaneous satellite measurements are observed above ground level, this study investigates the possibility of a time lag between satellite and surface mass-weighted mean diameter (D(sub m)), reflectivity (Z), and precipitation rate (R) observations. Results indicate that time lags vary up to 30 minutes after overpass time but are not consistent between cases. In addition, GPM Core D(sub m) retrievals are within Level I mission science requirements as compared to WPRF ground observations. Results also indicate GPM algorithms overestimate light rain (< 1.0 mm hr(exp -1)). Two very different stratiform rain vertical profiles show differing results when compared to ground reference data. A key finding of this study indicates multi-sensor DPR/GMI combined algorithms outperform single sensor DPR algorithm.

Charanjit S Pabla↗

Complete collision data set for electrons scattering on molecular hydrogen and its isotopologues: III. Vibrational excitation via electronic excitation and radiative decay

We present state-resolved cross sections for vibrational excitation via electronic excitation followed by radiative decay (ERD), for electrons scattering on all bound vibrational levels of the ground electronic state ($X\hspace{1.5 mm} ^1Σ_g^+$) of molecular hydrogen and its isotopologues (H 2 , HD, HT, D 2 , DT and T 2 ). We consider excitation of the singlet $\textit{n}$ = 2–3 states (where n refers to the united-atoms-limit principle quantum number) and account for all possible decay pathways back to the bound vibrational levels of the ground electronic state ($X\hspace{1.5 mm} ^1Σ_g^+$) to produce an estimate for the ERD cross sections. A selection of the results are presented in graphical form and a full data set is provided as both numerical values and analytic fit functions in supplementary data files. The uncertainty in the cross sections is estimated to be 11%, except for scattering on the highest bound vibrational level of HD, HT, D 2 , and DT, where the uncertainty is 21%. The data can be downloaded from the MCCC database at mccc-db.org.

74 ATOMIC AND MOLECULAR PHYSICS↗

Low-energy scattering of molecules and ions in a magnetic field

We describe calculations of elastic and inelastic scattering of neutral molecules and cold ions in a magnetic field. The molecule is assumed to have a magnetic and electric dipole moment. The external magnetic field splits the ground rovibrational energy levels of the molecule. The highest energy state within the ground rovibrational manifold increases in energy as the distance to the ion decreases leading to a repelling potential. At low energy, inelastic collisions are strongly suppressed due to the large distance of closest approach. Thus, a collision between a neutral molecule and a cold ion will lead to a decrease in the molecule’s kinetic energy with no change in internal energy. We present results for the specific case of OH molecules cooled by Be + , Mg + , or Ca + ions. Also, we perform molecular dynamics simulations of ions and molecules in a combined Paul trap and time-averaged orbiting potential trap. Furthermore, our results suggest that sympathetic cooling of neutral molecules by ions would be possible if cold ions and molecules could be simultaneously trapped.

74 ATOMIC AND MOLECULAR PHYSICS↗

Radiative lifetimes of the second negative system of O2(+)

The dipole moment of the A2Pi(u)-X2Pi(g) transition of O2(+) is calculated as a function of internuclear distance using ab initio methods. The band absorption oscillator strengths and band transition probabilities of the second negative system are derived and the resulting lifetimes are compared with experimental data. The high-lying v double prime levels of the ground state may decay into low-lying v prime levels of the excited state. The corresponding radiative lifetimes are calculated.

Wetmore, R. W.↗