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HALF-LIVES OF LONG-LIVED A-DECAY, B-DECAY, BB-DECAY AND SPONTANEOUS FISSION NUCLIDES.

Description: In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for a discussion session at the next meeting. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay and spontaneous fission decay. This report is preliminary but will provide a quick overview of the extensive table of data on the recommendations from that review.
Date: June 29, 2001
Creator: HOLDEN,N.E.
Partner: UNT Libraries Government Documents Department

SAVANNAH RIVER TECHNOLOGY CENTER MONTHLY REPORT AUGUST 1992

Description: 'This monthly report summarizes Programs and Accomplishments of the Savannah River Technology Center in support of activities at the Savannah River Site. The following categories are addressed: Reactor, Tritium, Separations, Environmental, Waste Management, General, and Items of Interest.'
Date: June 21, 1999
Creator: Ferrell, J.M.
Partner: UNT Libraries Government Documents Department

Measurement of radionuclides using ion chromatography and flow-call scintillation counting with pulse shape discrimination: Topical report, September 15, 1996--October 3, 1996, Tasks 1.11, 1.12 and 1.13

Description: Several flow-cell radiation detector systems are commercially available for quantification of aqueous radioactive solutions. These systems do not use the technique of pulse shape discrimination to identify the incident radiation and therefore are limited in environmental characterization application when coupled to an ion chromatography system. The advantages of the pulse shape discriminating flow-cell detector over the commercially available systems include: (1) lower minimum detectable activity for alpha radiation, (2) reduced radiological interferences that may exist between co-eluted alpha- and beta-emitting radionuclides, and (3) possible isotopic information from the ion chromatography system. For Tasks 1.1.1 and 1.1.2 of this project, several scintillation materials were investigated for pulse shape (alpha and beta) discrimination capabilities and the best candidate material was optimized. In addition, the following detector properties were also optimized: scintillator particle size, flow-cell tubing type, and electromagnetic as well as optical crosstalk between the photomultiplier tubes.
Date: April 1, 1997
Partner: UNT Libraries Government Documents Department

Direct measurement of strontium-90 and uranium-238 in soils on a real-time basis: 1994 summary report

Description: Traditional methodologies for quantitative characterization of radionuclide-contaminated soils over extended areas are often tedious, costly, and non-representative. A rapid characterization methodology was designed that provides reliable output with spatial resolution on the order of a few meters or less. It incorporates an innovative sensor of square plastic scintillating fibers that has been designed to be placed directly on or above a contaminated soil to detect and quantify high-energy beta particles associated with the decay chains of uranium and/or strontium. Under the direction and auspices of the DOE`s Characterization, Monitoring, and Sensor Technology Integrated Program, Pacific Northwest Laboratory (PNL) constructed a high-energy beta scintillation sensor that was optimized for the detection and quantification of uranium and strontium contamination in surface soils (in the presence of potentially interfering natural and anthropogenic radionuclides), demonstrated and evaluated this detector in various field and laboratory scenarios, and provides this document in completion of the aforementioned requirements.
Date: April 1, 1995
Creator: Schilk, A.J.; Hubbard, C.W.; Knopf, M.A. & Thompson, R.C.
Partner: UNT Libraries Government Documents Department

Hanford high level waste: Sample Exchange/Evaluation (SEE) Program

Description: The Pacific Northwest Laboratory (PNL)/Analytical Chemistry Laboratory (ACL) and the Westinghouse Hanford Company (WHC)/Process Analytical Laboratory (PAL) provide analytical support services to various environmental restoration and waste management projects/programs at Hanford. In response to a US Department of Energy -- Richland Field Office (DOE-RL) audit, which questioned the comparability of analytical methods employed at each laboratory, the Sample Exchange/Exchange (SEE) program was initiated. The SEE Program is a selfassessment program designed to compare analytical methods of the PAL and ACL laboratories using sitespecific waste material. The SEE program is managed by a collaborative, the Quality Assurance Triad (Triad). Triad membership is made up of representatives from the WHC/PAL, PNL/ACL, and WHC Hanford Analytical Services Management (HASM) organizations. The Triad works together to design/evaluate/implement each phase of the SEE Program.
Date: August 1, 1994
Creator: King, A.G.
Partner: UNT Libraries Government Documents Department

Methods for measuring the surface tritium inside TFTR using beta decay

Description: Three potential methods for measuring the surface tritium content of the TFTR vacuum vessel are described, each based on a different technique for measuring the in situ beta emission from tritium. These methods should be able to provide both a local and a global assessment of the tritium content within the top [approx] 1[mu]m of the inner wall surface.
Date: January 1, 1994
Creator: Zweben, S.J.; Johnson, D. & Hill, K. (Princeton Univ., NJ (United States). Plasma Physics Lab.) (and others)
Partner: UNT Libraries Government Documents Department

Pilot study risk assessment for selected problems at the Nevada Test Site (NTS)

Description: The Nevada Test Site (NTS) is located in southwestern Nevada, about 105 km (65 mi) northwest of the city of Las Vegas. A series of tests was conducted in the late 1950s and early 1960s at or near the NTS to study issues involving plutonium-bearing devices. These tests resulted in the dispersal of about 5 TBq of [sup 239,24O]Pu on the surficial soils at the test locations. Additionally, underground tests of nuclear weapons devices have been conducted at the NTS since late 1962; ground water beneath the NTS has been contaminated with radionuclides produced by these tests. These two important problems have been selected for assessment. Regarding the plutonium contamination, because the residual [sup 239]Pu decays slowly (half-life of 24,110 y), these sites could represent a long-term hazard if they are not remediated and if institutional controls are lost. To investigate the magnitude of the potential health risks for this no-remediation case, three basic exposure scenarios were defined that could bring individuals in contact with [sup 239,24O]Pu at the sites: (1) a resident living in a subdivision, (2) a resident farmer, and (3) a worker at a commercial facility -- all located at a test site. The predicted cancer risks for the resident farmer were more than a factor of three times higher than the suburban resident at the median risk level, and about a factor of ten greater than the reference worker at a commercial facility. At 100 y from the present, the 5, 50, and 95th percentile risks for the resident farmer at the most contaminated site were 4 x 10[sup [minus]6], 6 x 10[sup [minus]5], and 5 x 10[sup [minus]4], respectively. For the assessment of Pu in surface soil, the principal sources of uncertainty in the estimated risks were population mobility, the relationship between indoor and outdoor ...
Date: June 1, 1993
Creator: Daniels, J.I. (ed.)
Partner: UNT Libraries Government Documents Department

Recovery and purification of nickel-63 from HFIR-irradiated targets

Description: The production of large quantities of high-specific-activity [sup 63]Ni (>10 Ci/g) requires both a highly enriched [sup 62]Ni target and a long irradiation period at high neutron flux. Trace impurities in the nickel and associated target materials are also activated and account for a significant fraction of the discharged activity and essentially all of the gamma activity. While most of these undesirable activation products can be removed as chloride complexes during anion exchange, chromium, present at [sup 51]Cr, and scandium, present as [sup 46]Sc, are exceptions and require additional processing to achieve the desired purity. Optimized flowsheets are discussed based upon the current development and production experience.
Date: June 1, 1993
Creator: Williams, D.F.; O'Kelley, G.D.; Knauer, J.B.; Porter, C.E. & Wiggins, J.T.
Partner: UNT Libraries Government Documents Department

Development of more efficacious [Tc]-99m organ imaging agents for use in nuclear medicine by analytical characterization of radiopharmaceuticals

Description: This research program is detailed at development of more efficacious technetium-99m radiopharmaceuticals for use as imaging agents in diagnostic nuclear medicine. We seek to isolate and develop distinct site imaging agents to provide diagnostic information concerning a given pathological condition. Analytical techniques are being developed to enable complete analysis of radiopharmaceutical preparations so that individual complexes can be characterized with respect to imaging efficacy and to enable a radiopharmaceutical to be monitored after injection into a test animal to determine the species that actually accumulates in an organ to provide the image. Administration of the isolated, single most effective imaging complex, rather than a mixture of technetium-containing complexes, wi-11 minimize radiation exposure to the patient and maximize diagnostic information available to the clinician. This report specifically describes the development of capillary electrophoresis (CE) for characterizating diphosphonate skeletal imaging agents. Advances in the development of electrochemical and fiber optic sensors for Tc and Re imaging agents are described. These sensors will ultimately be capable of monitoring a specific chemical state of an imaging agent in vivo after injection into a test animal by implantation in the organ of interest.
Date: May 3, 1993
Creator: Heineman, W.R.
Partner: UNT Libraries Government Documents Department

Conceptual design report for the University of Rochester cryogenic target delivery system

Description: The upgrade of the Omega laser at the University of Rochester's Laboratory for Laser Energetics (UR/LLE) will result in a need for large targets filled with D[sub 2] or Dt and maintained at cryogenic temperatures. This mandates a cryogenic target delivery system capable of filling, layering, characterizing and delivering cryogenic targets to the Omega Upgrade target chamber. The program goal is to design, construct, and test the entire target delivery system by June 1996. When completed (including an operational demonstration), the system will be shipped to Rochester for reassembly and commissioning in time for the Omega Upgrade cryogenic campaign, scheduled to start in 1998. General Atomics has been assigned the task of developing the conceptual design for the cryogenic target delivery system. Design and fabrication activities will be closely coordinated with the University of Rochester, Lawrence Livermore National laboratory (LLNL) and Los Alamos National Laboratory (LANL), drawing upon their knowledge base in fuel layering and cryogenic characterization. The development of a target delivery system for Omega could also benefit experiments at Lawrence Livermore National Laboratory and the other ICF Laboratories in that the same technologies could be applied to NOVA, the National Ignition Facility or the future Laboratory Microfusion Facility.
Date: May 1, 1993
Creator: Fagaly, R. L.; Alexander, N. B.; Bourque, R. F.; Dahms, C. F.; Lindgren, J. R.; Miller, W. J. (General Atomics, San Diego, CA (United States)) et al.
Partner: UNT Libraries Government Documents Department

The development of in vitro mutagenicity testing systems using T-lymphocytes

Description: This annual report describes progress in studies on hprt mutations induced by radon or Indium 111 along with the corresponding mutation frequency, cloning and molecular spectra in human T-lymphocytes. Parallel studies on the mutation susceptibility between individuals is being investigated by hprt mutation studies on ataxia telangiectasia and xeroderma pigmentosum.
Date: May 1, 1993
Creator: Albertini, R.J.
Partner: UNT Libraries Government Documents Department

Surveillance of Site A and Plot M

Description: The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for CY 1992 are presented. The surveillance program is the ongoing remedial action that resulted from the 1976--1978 radiological characterization of the site. That study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells. The current program consists of sample collection and analysis of air, surface and subsurface water, and bottom sediment. The results of the analyses are used to (1) determine the migration pathway of water from the burial ground (Plot M) to the hand-pumped picnic wells, (2) establish if buried radionuclides other than hydrogen-3 have migrated, and (3) generally characterize the radiological environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Tritiated water continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. For many years it was the only radionuclide found to have migrated in measurable quantities. Analyses since 1984 have indicated the presence of low levels of strontium-90 in water from a number of boreholes next to Plot M. The available data does not allow a firm conclusion as to whether the presence of this nuclide represents recent migration or movement that may have occurred before Plot M was capped. The results of the surveillance program continue to indicate that the radioactivity remaining at Site A/Plot M does not endanger the health or safety of the public visiting the site, using the picnic area, or living in the vicinity.
Date: May 1, 1993
Creator: Golchert, N.W.
Partner: UNT Libraries Government Documents Department

[beta][sup +] decay and cosmic-ray half-lives of [sup 143]Pm and [sup 144]Pm

Description: The positron decay partial half-lives of [sup 143]Pm and [sup 144]Pm are needed to assess the viability of elemental Pm as a cosmic-ray clock. We have conducted experiments to measure the [beta][sup +] branches of these isotopes; we find [beta][sup +] branches of these isotopes; we find [beta][sup +] branches of <5.7 [times]10[sup [minus]8] for [sup 143]Pm and <8[times]10[sup [minus] 7] for [sup 144]Pm. Through these branches are a factor of 20 lower than the previous experimental limits, the resulting partial half-lives are still too uncertain to permit any firm conclusions.
Date: April 12, 1993
Creator: Hindi, M.M. (Tennessee Technological Univ., Cookeville, TN (United States). Dept. of Physics); da Cruz, M.T.F.; Larimer, R.M.; Lesko, K.T.; Norman, E.B. (Lawrence Berkeley Lab., CA (United States)); Sur, B. (Lawrence Berkeley Lab., CA (United States) Queen's Univ., Kingston, ON (Canada). Dept. of Physics) et al.
Partner: UNT Libraries Government Documents Department

Derivation of strontium-90 and cesium-137 residual radioactive material guidelines for the Laboratory for Energy-Related Health Research, University of California, Davis

Description: Residual radioactive material guidelines for strontium-90 and cesium-137 were derived for the Laboratory for Energy-Related Health Research (LEHR) site in Davis, California. The guideline derivation was based on a dose limit of 100 mrem/yr. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD, was used in this evaluation; this code implements the methodology described in the DOE manual for implementing residual radioactive material guidelines. Three potential site utilization scenarios were considered with the assumption that, for a period of 1,000 years following remedial action, the site will be utilized without radiological restrictions. The defined scenarios vary with regard to use of the site, time spent at the site, and sources of food consumed. The results of the evaluation indicate that the basic dose limit of 100 mrem/yr will not be exceeded within 1,000 years for either strontium-90 or cesium-137, provided that the soil concentrations of these radionuclides at the LEHR site do not exceed the following levels: 71,000 pCi/g for strontium-90 and 91 pCi/g for cesium-137 for Scenario A (researcher: the expected scenario); 160,000 pCi/g for strontium-90 and 220 pCi/g for cesium-137 for Scenario B (recreationist: a plausible scenario); and 37 pCi/g for strontium-90 and 32 pCi/g for cesium-137 for Scenario C (resident farmer ingesting food produced in the contaminated area: a plausible scenario). The derived guidelines are single-radionuclide guidelines and are linearly proportional to the dose limit used in the calculations. In setting the actual strontium-90 and cesium-137 guidelines for the LEHR site, DOE will apply the as low as reasonably achievable (ALARA) policy to the decision-making process, along with other factors such as whether a particular scenario is reasonable and appropriate.
Date: April 1, 1993
Creator: Nimmagadda, M. & Yu, C.
Partner: UNT Libraries Government Documents Department

Excitation rate and background measurements during LIF studies on krypton

Description: The Krypton Isotope Laser Analysis (KILA) method is being developed at the Pacific Northwest Laboratory (PNL) to measure [sup 85]Kr concentrations in small air samples. The technique uses high-resolution lasers to excite individual isotopes of krypton specifically to induce [sup 85]Kr to fluorescence for detection by optical means. Production of krypton metastables via two-photon excitation to the 2p[sub 6] state has been shown to be 0.15% efficient in 0.13 mTorr of krypton--sufficiently high to demonstrate overall feasibility of the KILA method. Since this goal was met, focus has been directed toward development of a working vacuum ultraviolet (VUV) fluorescence detection system and toward understanding the VUV background. This report describes the progress made in these two areas. The second step of the KILA process is to optically pump all except the [sup 85]Kr isotopes from the metastable state back to the ground state using laser-induced fluorescence (LIF). The rate of this process and the VUV background afterward will determine the sensitivity and selectivity of the KILA approach. De-excitation of the metastable population was accomplished via one-photon absorption of a continuous-wave (c-w) laser to the 2p[sub 8] energy level. Non-isotopically selective de-excitation rates as high as 5 [times] 10[sup 5] sec[sup [minus]1] have been measured, yielding a signal-to-background ratio of >10[sup 6]. The lifetime of the metastables is 1.2 msec in 200 mTorr of neon--much longer than the time required to de-excite krypton metastables and to detect fluorescence produced by [sup 85]Kr. After attaining these high de-excitation rates, a gated VUV detection system was built with a dynamic range large enough to measure a small background following de-excitation of large metastable populations. Future experiments will focus on reducing the background level by another 2--3 orders of magnitude and perfecting the isotopically selective de-excitation technique with known samples.
Date: April 1, 1993
Creator: Whitehead, C.A.; Cannon, B.D. & Wacker, J.F.
Partner: UNT Libraries Government Documents Department

F- and H-Area Sewage Sludge Application Sites groundwater monitoring report

Description: Samples from the four wells at the F-Area Sewage Sludge Application Site (FSS wells) and the three wells at the H-Area Sewage Sludge Application Site (HSS wells) are analyzed quarterly for constituents as required by South Carolina Department of Health and Environmental Control Construction Permit 12,076 and, as requested, for other constituents as part of the Savannah River Site Groundwater Monitoring Program. Annual analyses for other constituents, primarily metals, also are required by the permit. During fourth quarter 1992, the FSS wells also were analyzed for a number of other constituents not required by the permit. Historically and currently, no permit-required analytes exceed standards at the F- and H-Area Sewage Sludge Application Sites except iron, lead, and manganese, which occur in elevated concentrations frequently in FSS wells. Lead concentrations exceeded the final Primary Drinking Water Standards during fourth quarter 1992, an event that is concurrent with a change in sampling procedures. Tritium is the primary nonpermit constituent that exceeds standards at the F-Area Sewage Sludge Application Site. Other constituents also exceed standards at this site but only sporadically.
Date: April 1, 1993
Partner: UNT Libraries Government Documents Department

An improvement in the value of the energy of the first excited state in [sup 229]Th

Description: It has been known for many years that the first excited state of [sup 229]Th lies close to the ground state. Originally this energy was given as < 0.1 keV; later, the authors reported a value of [minus]1 [plus minus] 4 eV. Since the existence of a nuclear state at this very low energy is of considerable interest, measurements of its energy, half-life and modes of excitation and deexcitation are important. In an attempt to improve the level energy, the authors have measured over 175 [gamma]-ray spectra with several combinations of radionuclides. In comparison with their earlier study, they have considered more [gamma] rays in [sup 229]Th, used more well-measured reference lines, used more detectors, used detectors with better low-energy resolution, more closely matched peak count rates, and specifically considered certain systematic errors. From this large set of measurements they have deduced a value of 3.5 [plus minus] 1.0 eV for the energy of this level.
Date: April 1, 1993
Creator: Helmer, R.G. & Reich, C.W.
Partner: UNT Libraries Government Documents Department

Leach testing of in situ stabilization grouts containing additives to sequester contaminants

Description: This document discusses laboratory testing performed by Pacific Northwest Laboratory (PNL) for Westinghouse Hanford Company (WHC) of special grout formulations that incorporate specific sequestering agents to help improve the ability of the cement to resist contaminant leaching. To enhance the sequestering of contaminants we chose five additives to introduce (singly) to the control cement. The additives were Florida pebble phosphate, clinoptilolite (a natural zeolite), ferrous sulfide (a reductant), a mixed bed organic ion exchange resin and a proprietary anion-adsorbing mixed metal oxide. These additives were added one per test to the standard formulation and used to encapsulate a diluted high-salt alkaline liquid waste that is produced after various processes to remove uranium and plutonium from spent nuclear fuel. This report documents the testing of these additives.
Date: April 1, 1993
Creator: Serne, R.J.; Ames, L.L.; Martin, P.F.C.; LeGore, V.L.; Lindenmeier, C.W. (Pacific Northwest Lab., Richland, WA (United States)) & Phillips, S.J. (Westinghouse Hanford Co., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department

Low Z impurity ion extraction from TFTR ion sources

Description: TFTR deuterium neutral beams have been operated unintentionally with significant quantities of extracted water ions. Water has been observed with an Optical Multichannel Analyzer (OMA) during beam extraction when small water leaks were present within the arc chamber. These leaks were thermally induced with the contamination level increasing linearly with pulse length. 6% of the beam current was attributed to water ions for the worst leak, corresponding to an instantaneous value of 12% at the end of a 1.5 s pulse. A pre-calorimeter collimator was damaged as a result of this operation. A similar contamination is observed during initial operation of ion sources exposed to air. This latter contamination is attributed to the synthesis, from adsorbed air, of either D[sub 2]O or the indistinguishable ND[sub 3]. Initial operation of new ion sources typically produces a contamination level of [approximately]2%. These impurities are reduced to undetectable levels after 50 to 100 beam pulses. Once a water molecule is present in the plasma generator, it is predominantly ionized rather than dissociated, resulting in the extraction of only trace amounts of hydrogenated ions. The addition of water to the extracted beam also reduces the optimum perveance, moving the typical underdense operating point closer to optimum, causing the frequency of grid faults to increase. Close to 90% of the water extracted from ion sources with water leaks was deuterated, implying that the potential exists for the production of tritiated water during TFTR's forthcoming DT operation. Isotope exchange in the plasma generator takes place rapidly and is believed to be surface catalyzed. The primary concern is with O implanted into beam absorbers recombining with tritium, and the subsequent hold up of T[sub 2]O on cryopanels. Continuous surveillance with the OMA diagnostic during DT operation will ensure that ion sources with detectable water are not operated ...
Date: April 1, 1993
Creator: Kamperschroer, J.H.; Grisham, L.R.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A. et al.
Partner: UNT Libraries Government Documents Department

Nuclear Medicine Program progress report for quarter ending March 31, 1993

Description: We have exploring the possibility of measuring urinary radioactivity as an index of pancreatic lipase activity after oral administration of a new triglyceride containing a radioactive iodine-1 25-labeled fatty acid moiety. The new agent, 1,2-dipalmitoyl-3[15-(p-iodophenyl)pentandecan-l-oyl]-racglycerol (1,2-Pal-3-IPPA), was prepared by the thallation-iodide displacement method. Following oral gavage of the radioiodinated triglyceride to rats, about 30% of the administered activity was excreted in 24 hours in the urine. In normal human controls an higher urinary excretion (of about 75% was observed. In this report, we describe an evaluation of the metabolites excreted in the urine and the chemical species stored in adipose from rats. The urine activity co-chromatographed with hippuric acid by TLC indicating conjugation of the IPPA metabolites. Release of the acidic components from the conjugated excretory products by acid hydrolysis of the urine provided the radioactive acidic IPPA metabolites. Analysis of the Folch extracts of fat samples from rats demonstrated that the radioactive components co-chromatographed In the triglyceride region. Recent studies in patients with compromised pancreatic exocrine function have demonstrated significantly decreased 24 hr. urinary excretion of about 25%, following oral administration of [1 -1 31]-1,2-Pal-3-IPPA. Thus, urine analysis after oral administration of [I -1 31]-1,2-Pal-3-IPPA may be a simple, non-invasive tool for the clinical evaluation of various diseases involving dietary fat digestion.
Date: April 1, 1993
Creator: Knapp, F.F. Jr.; Ambrose, K.R.; Beets, A.L.; Callahan, A.P.; McPherson, D.W.; Mirzadeh, S. et al.
Partner: UNT Libraries Government Documents Department

Nuclear structure models: Applications and development. [Department of Physics, Tennessee Technological University, Cookeville, Tennessee]

Description: This report summarizes the progress made during the period July 1, 1992 to April 30, 1993. The study of rotational structure at moderate spins in odd-odd nuclei (Section 1) has continued into the A [approximately] 80 region. Recent experimental data for the positive parity band in [sup 82]Y, including absolute BM1 and BE2 values, are rather well described with a prolatish'' triaxial shape and a [pi]g[sub 9/2] [direct product] [nu]g[sub 9/2] configuration. Little effect from a protonneutron interaction has been found so far. Current studies of odd mass nuclei (Section 2) are mainly focussing on low spin, low energy states in the A [approximately] 130 region as a probe to the evolving collectivity. These projects involve direct collaboration with experimental colleagues. Finally, a view of the microscopic foundation of particle-core coupling models approached from the equation of motion method is presented (Section 3).
Date: April 1, 1993
Creator: Semmes, P.B.
Partner: UNT Libraries Government Documents Department

On the 17-keV neutrino

Description: A brief review on the status of the 17-keV neutrino is presented. Several different experiments found spectral distortions which were consistently interpreted as evidence for a heavy neutrino admixture in [beta] decay. Recent experiments, however, rule out the existence of a 17-keV neutrino as well as escaping criticisms of earlier null results. Moreover, the majority of positive results have been reinterpreted in terms of instrumental effects, despite the need for a different explanation in each case. Anomalies persist in the low energy region of the tritium spectrum which deserve further investigation.
Date: April 1, 1993
Creator: Hime, A.
Partner: UNT Libraries Government Documents Department

[beta][sup +] decay and cosmic-ray half-life of [sup 54]Mn

Description: We performed a search for the [beta][sup +] branch of [sup 54]Mn decay. As a cosmic ray, [sup 54]Mn, deprived of its atomic electrons, can decay only via [beta][sup +] and [beta][sup [minus]] decay, with a half-life of the order of 10[sup 6] yr. This turns [sup 54] Mn into a suitable cosmic chronometer for the study of cosmic-ray confinement times. We searched for coincident back-to-back 511-keV [gamma]-rays using two germanium detectors inside a Nal(Tl) annulus. An upper limit of 2[times]10[sup [minus]8] was found for the [beta][sup +] decay branch, corresponding to a lower limit of 13.7 for the log ft value.
Date: March 29, 1993
Creator: da Cruz, M.T.F.; Norman, E.B.; Chan, Y.D.; Garcia, A.; Larimer, R.M.; Lesko, K.T. et al.
Partner: UNT Libraries Government Documents Department

Environmental Implementation Plan

Description: The purpose of the Environmental Implementation Plan (EIP) is to show the current and future (five years) environmental plans from individual site organizations and divisions, as well as site environmental programs and initiatives which are designed to protect the environment and meet or exceed changing environmental/regulatory requirements. Communicating with site organizations, departments, and committees is essential in making the site's environmental-planning process work. The EIP gives the site the what, when, how, and why for environmental requirements. Through teamwork and proactive planning, a partnership for environmental excellence is formed to achieve the site vision for SRS to become the recognized model for Environmental Excellence in the Department of Energy's Nuclear Weapons Complex.
Date: March 15, 1993
Partner: UNT Libraries Government Documents Department