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Consequence analysis of a postulated NaOH release from the 2727-W sodium storage facility

Description: Toxicological and radiological consequences were calculated for a maximum sodium fire in the 2727-W Sodium Storage Facility. The sodium is solid and cannot leak out of the tanks. The maximum fire therefore corresponded to the maximum cross-sectional area of one tank. It was shown that release of the entire facility inventory of 22 Na is insufficient to produce an appreciable effect.
Date: September 27, 1996
Creator: Himes, D.A.
Partner: UNT Libraries Government Documents Department

Consequence analysis of a postulated NaOH release from the 2727-W sodium storage facility

Description: Toxicological and radiological consequences were calculated for a maximum sodium fire in the 2727-W Sodium Storage Facility. The sodium is solid and cannot leak out of the tanks. The maximum fire therefore corresponded to the maximum cross-sectional area of one tank. It was shown that release of the entire facility inventory of {sup 22}Na is insufficient to produce an appreciable effect.
Date: August 2, 1996
Creator: Himes, D.A., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Assessment of radiological releases from the NuMI facility during MINOS and NOvA operations

Description: This report makes projections of the radiological releases from the NuMI facility during operations for the MINOS and NO ?A experiments. It includes an estimate of the radionuclide levels released into the atmosphere and the estimated tritium and sodium-22 concentrations in the NuMI sump water and Fermilab pond system. The analysis was performed for NuMI operations with a beam power on target increased from the present 400 kW design up to a possible 1500 kW with future upgrades. The total number of protons on target was assumed to be 18 x 10{sup 20} after the completion of MINOS and 78 x 10{sup 20} after the completion of NO ?A.
Date: April 1, 2007
Creator: Martens, Mike
Partner: UNT Libraries Government Documents Department

High energy beam lifetime analysis

Description: We have developed a positron lifetime defect analysis capability based on a 3 MeV electrostatic accelerator. The high energy beam lifetime spectrometer is operational with a 60 mCi {sup 22}Na source providing a current of 7 10{sup 5} positrons per second. Lifetime data are derived from a thin plastic transmission detector providing an implantation time and a BaF{sub 2} detector to determine the annihilation time. Positron lifetime analysis is performed with a 3 MeV positron beam on thick sample specimens at counting rates in excess of 2000 per second. The instrument is being used for bulk sample analysis and analysis of samples encapsulated in controlled environments for in situ measurements.
Date: May 1, 1997
Creator: Howell, R.H.; Sterne, P.A.; Hartley, J. & Cowan, T.E.
Partner: UNT Libraries Government Documents Department

Nucleosynthesis and the nova outburst

Description: A nova outburst is the consequence of the accretion of hydrogen rich material onto a white dwarf and it can be considered as the largest hydrogen bomb in the Universe. The fuel is supplied by a secondary star in a close binary system while the strong degeneracy of the massive white dwarf acts to contain the gas during the early stages of the explosion. The containment allows the temperature in the nuclear burning region to exceed 10{sup 8}K under all circumstances. As a result a major fraction of CNO nuclei in the envelope are transformed into {beta}{sup +}-unstable nuclei. We discuss the effects of these nuclei on the evolution. Recent observational studies have shown that there are two compositional classes of novae; one which occurs on carbon-oxygen white dwarfs, and a second class that occurs on oxygen-neon-magnesium white dwarfs. In this review we will concentrate on the latter explosions since they produce the most interesting nucleosynthesis. We report both on the results of new observational determinations of nova abundances and, in addition, new hydrodynamic calculations that examine the consequences of the accretion process on 1.0M{sub {circle_dot}}, 1.25M{sub {circle_dot}}, and 1.35M{sub {circle_dot}} white dwarfs. Our results show that novae can produce {sup 22}Na, {sup 26}Al, and other intermediate mass nuclei in interesting amounts. We will present the results of new calculations, done with updated nuclear reaction rates and opacities, which exhibit quantitative differences with respect to published work.
Date: December 31, 1995
Creator: Starrfield, S.; Truran, J.W.; Wiescher, M. & Sparks, W.M.
Partner: UNT Libraries Government Documents Department

Viscous liquid barrier demonstration at the Brookhaven National Laboratory Linac Isotope Producer

Description: Groundwater monitoring has detected tritium ({sup 3}H) and {sup 22}Na contamination down gradient from the Brookhaven LINAC Isotope Producer (BLIP), located at Brookhaven National Laboratory (BNL). Site characterization studies indicate that the BLIP is the source of contamination. The highest measured values for {sup 3}H were 52,400 pCi/L recorded less than 100 feet south (down gradient) of the BLIP facility. The BLIP produces radioisotopes that are crucial in nuclear medicine for both research and clinical use. The BLIP also supports research on diagnostic and therapeutic radiopharmaceuticals. During operation a proton beam impinges a target (typically salts encapsulated in stainless steel) to produce the required radioisotopes. The proton beam is completely absorbed prior to reaching the soils surrounding the target shaft. However, secondary neutrons are produced that reach the soil causing activation products to form. Among the longer-lived isotopes of concern are tritium and {sup 22}Na. Both of these isotopes have the potential to negatively impact the groundwater below the BLIP. Several corrective actions have been implemented at the BLIP facility in response to tritium detection in the groundwater. The first actions were to improve surface water management (e.g. storm water down spouts) and the installation of a gunite cap around the BLIP facility. These measures are designed to minimize water flow through the activated soils in the vicinity of BLIP. In conjunction with these improvements, BNL is installing a close-proximity subsurface barrier in the activated soils beneath the BLIP facility. The barrier will prevent water migration through the activated soil zone as well as prevent activation product migration out of the zone. To minimize impacts on the operation of the BLIP requires in-situ barrier installation using low energy techniques that will not disturb the alignment of the BLIP or nearby accelerator beams. BNL chose an innovative barrier technology termed Viscous ...
Date: February 27, 2000
Creator: Heiser, J. H.; Sullivan, T.; Ludewig, H.; Brower, J.; North-Abbott, M.; Manchester, K. et al.
Partner: UNT Libraries Government Documents Department

Proton resonance spectroscopy. Quarterly technical progress report, December 1992--November 1995

Description: Work on chaos in the low-lying levels of nuclei has continued on several fronts. The major effort has been study of the {sup 29}Si(p,{gamma}) reaction with the goal of establishing a complete level scheme for {sup 30}P and analyzing the eigenvalue fluctuations for evidence of chaos. These measurements are in progress, and the current status is described. A related topic is the search for different signatures of chaos which do not require the extremely high degree of completeness and purity necessary for eigenvalue analyses; those efforts are discussed in Sections 2 and 3. The possibility of studying both parity violation and time-reversal invariance violation with charged particle resonances has been explored by performing calculations using experimentally measured resonance parameters. Large enhancements are indeed available; the results are discussed in Sections 4 and 5. Preparations for an experimental study of parity violation using these techniques are ongoing. An undergraduate project searching for experimental evidence of a parity dependence of level density is discussed in Section 6. A number of improvements to the operation of the TUNL KN accelerator have been implemented in the past three years. These are described in Section 7.
Date: November 1, 1995
Creator: Shriner, J.F. Jr.
Partner: UNT Libraries Government Documents Department


Description: A portable assembly containing a vertical-bend dipole magnet has been designed and installed immediately down-beam of the Compton electron-laser interaction chamber on beamline 1 of the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). The water-cooled magnet designed with field strength of up to 0.7 Tesla will be used as a spectrometer in the Thompson scattering and vacuum acceleration experiments, where field-dependent electron scattering, beam focusing and energy spread will be analyzed. This magnet will deflect the ATF's 60 MeV electron-beam 90{sup o} downward, as a vertical beam dump for the Compton scattering experiment. The dipole magnet assembly is portable, and can be relocated to other beamlines at the ATF or other accelerator facilities to be used as a spectrometer or a beam dump. The mechanical and shielding calculations are presented in this paper. The structural rigidity and stability of the assembly were studied. A square lead shield surrounding the assembly's Faraday Cup was designed to attenuate the radiation emerging from the 1 inch-copper beam stop. All photons produced were assumed to be sufficiently energetic to generate photoneutrons. A safety evaluation of groundwater tritium contamination due to the thermal neutron capturing by the deuterium in water was performed, using updated Monte Carlo neutron-photon coupled transport code (MCNP). High-energy neutron spallation, which is a potential source to directly generate radioactive tritium and sodium-22 in soil, was conservatively assessed in verifying personal and environmental safety.
Date: September 5, 2002
Partner: UNT Libraries Government Documents Department


Description: A Po/sup 210/ source was used to furnish a reliab1e ground for both electron and positron sources. This was done to prevent the electron and positron sources from charging during BETA spectral studies in magnetic lens spectrometers. An approximately 20- mu c Po/sup 210/ source was placed 1.2 in. behind a 4- mu c Na/sup 2 / 2>s positron emitter backed by 20- mu g/cm/sup 2/ Formvar in the spectrometer; this arrangement resulted in a charging rate decrease of approximately 80%. When the source was placed 0.5 in. away, no charging was detectable over a period of more than one week. The discharge is attributed mainly to the loss of electrons from the source and backing caused by ionization of alpha particles since few alpha particles are stopped near the source. (B.O.G.)
Date: December 1, 1960
Creator: Nichols, R.T. & Jensen, E.N.
Partner: UNT Libraries Government Documents Department

Solid neon moderated electrostatic or magnetic positron beam

Description: A high intensity variable energy positron beam has been constructed at Brookhaven National Laboratory (BNL). Positrons from a 97mCi {sup 22}Na source are moderated by a thin layer of solid neon. A magnetic guiding system delivered up to 5{times}10{sup 6}e{sup +}/sec to an experiment. Currently tests are under way to facilitate the operation with the magnetic guiding system or -- for other experimental sites -- with an electrostatic beam transport. The electrostatic lenses are fabricated from {mu}-metal. No compensation of the earth magnetic field is required. Several experiments can utilize the beam on a time sharing basis. In the near future the source will be replaced by {sup 64}Cu which has a much higher activity. Beam intensities up to 10{sup 9}e{sup +}/sec are expected.
Date: December 31, 1991
Creator: Weber, M.; Schwab, A.; Becker, D. & Lynn, K. G.
Partner: UNT Libraries Government Documents Department

Ground-water activation from the upcoming operation of MI40 beam absorber

Description: During the course of normal operation, a particle accelerator can produce radionuclides in the adjacent soil and in the beam line elements through the interactions of accelerated particles and/or secondary particles produced in the beam absorbers, targets, and sometimes elsewhere through routine beam losses. The production and concentration of these radionuclides depends on the beam parameters such as energy, intensity, particle type, and target configuration. The radionuclides produced in the soil can potentially migrate to the ground water. Soil activation and migration to the ground water depends on the details of the local hydrogeology. Generally, very few places such as the beam stops, target stations, injection and extraction sectors can have high enough radiation fields to produce radionuclides in the soil outside the enclosures. During the design, construction, or an upgrade in the intensity of existing beams, measures are taken to minimize the production of activated soil. The only leachable radionuclides known to be produced in the Fermilab soil are {sup 3}H, {sup 7}Be , {sup 22}Na, {sup 45}Ca and {sup 54}Mn and it has been determined that only {sup 3}H, and {sup 22}Na, because of their longer half lives and greater leachabilities, may significantly impact ground water resources.In the past, Fermilab has developed and used the Single Resident Well Model (SRWM) to estimate the ground water activation. Recently, the Concentration Model (CM), a more realistic method which depends on the site hydrogeology has been developed to decide the shielding requirements of the high radiation sites, and to calculate the ground water activation and its subsequent migration to the aquifer. In this report, the concentration of radionuclide released to the surface waters and the aquifer around the MI40 beam absorber are calculated. Subsequently, the ultimate limit on the primary proton beam intensity to be aborted on the Main Injector beam ...
Date: September 1, 1996
Creator: Bhat, C.M. & Read, A.L.
Partner: UNT Libraries Government Documents Department


Description: Fission product cross sections of (p,f)-reaction in thin samples of {sup 208}Pb, {sup nat}HgO, {sup nat}W irradiated with high-energy protons are measured. The irradiations were made using proton beams extracted from the ITEP synchrotron. The nuclide yields were {gamma}-spectrometered directly using a high-resolution Ge-detector. The GENIE2000 code was used to process the measured {gamma}-spectra and the ITEP-developed SIGMA code was used together with the PCNUDAT nuclear decay database to identify the {gamma}-lines and to determine the cross-sections. The {sup 27}Al(p,x){sup 22}Na reaction was used to monitor the proton flux. The LAHET, CEM2k, CEM95, CASCADE/INPE, CASCADE, INUCL, and YIELDX codes were used for computer simulation of the products measured. Comparison of simulated and experimental values shows insufficient predictive power of the existing fission models. The results obtained are of importance in studying the parameters of the Pb, Hg and W target modules of the hybrid Accelerator-Driven System (ADS) facilities.
Date: December 1, 2000
Creator: others], Y. TITARENKO
Partner: UNT Libraries Government Documents Department

Measurement of proton production cross sections of {sup 10}Be and {sup 26}Al from elements found in lunar rocks

Description: Cosmic rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of solar cosmic rays and {similar_to}87% of galactic cosmic rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we present new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.
Date: July 1, 1996
Creator: Sisterson, J.M.; Kim, K. & Englert, P.A.J.
Partner: UNT Libraries Government Documents Department

On the half-life of {sup 44}Ti

Description: One of the few long-lived gamma-ray emitting radioisotopes expected to be produced in substantial quantities during a supernova explosion is {sup 44}Ti. The relevant portions of the decay schemes of {sup 44}Ti and its daughter {sup 44}Sc are shown. {sup 44}Ti decays to {sup 44}Sc emitting {gamma} rays of 68 and 78 keV. {sup 44}Sc subsequently decays with a 3.93-hour half life to {sup 44}Ca emitting an 1,157-keV {gamma}ray. This characteristic 1,157-keV {gamma} ray from the decay of {sup 44}Ti has recently been observed from the supernova remnant Cas A. In order to compare the predicted {gamma}-ray flux to that actually observed from this remnant, one must know the half-life of {sup 44}Ti. However, published values for this quantity range from 46.4 to 66.6 years. Given that the Cas A supernova is believed to have occurred approximately 300 years ago, this translates to an uncertainty by a factor of 4 in the amount of {sup 44}Ti ejected by this supernova. Thus, in order to provide an accurate and reliable value for this important quantity, the authors have performed a new experiment to determine the half-life of {sup 44}Ti. The authors produced {sup 44}Ti via the {sup 45}Sc(p,2n) reaction using 40 MeV protons from the Lawrence Berkeley National Laboratory`s 88-Inch Cyclotron. In the present experiment, the authors attempted to use all three {sup 44}Ti {gamma}-ray lines to determine its half life. However, analysis of the {sup 241}Am and {sup 137}Cs lines produced an incorrect value for the half life of each of these isotopes. On the other hand, the analysis of the {sup 22}Na line produced a result that agreed to within 0.5% of the known value of 2.603 years. Thus, they decided to concentrate their effort on the analysis of the 1,157-keV line. The half life of {sup 44}Ti that ...
Date: June 19, 1996
Creator: Norman, E.B.; Browne, E.; Chan, Y.D.; Goldman, I.D.; Larimer, R.M.; Lesko, K.T. et al.
Partner: UNT Libraries Government Documents Department

Human radiation studies: Remembering the early years: Oral history of physician James S. Robertson, M.D., Ph.D., conducted January 20, 1995

Description: This report is a transcript of in interview of Dr. James S. Robertson by representatives of the DOE Office of Human Radiation Experiments. Dr. Robertson was chosen for this interview because of his research at Brookhaven National Laboratory, especially on Boron Neutron Capture Therapy (BNCT); his work at the United States Naval Defense Laboratory; and his work at the Atomic Energy Commission. After a brief biographical sketch Dr. Robertson discusses research on human subjects at Berkeley, his contributions to the beginnings of Neutron Capture Therapy at Brookhaven, his participation with the Brookhaven Human Use Committee, his involvement in the study of the effects of Castle Bravo event on the Marshallese, and his work with the Naval Radiological Defense Laboratory.
Date: September 1, 1995
Partner: UNT Libraries Government Documents Department


Description: In the bombardment of Al foils with 28-Bev protons the following cross sections (in mb) for production of the indicated nuclides were obtained: Be/sup 7/ , 7.9 plus or minus 0.5; F/sup 18/, 6.0 plus or minus 0.3; C/sup 11/, 4.7 plus or minus 0.2; Na/sup 22/, 9.8 plus or minus 0.6. N/sup 13/, 1.18 plus or minus 0.07; Na/su p 24/, 8.3 plus or minus 0.5; O/sup 15/, 3.6 plus or minus 1.0, Mg/sup 27/, 0.067 plus or minus 0.006. An upper limit for the Ne/ sup 24/ eross section of 0.6 mb was obtained. The Mg/sup 27/ cross section has been corrected for secondary reactions and represents only production by primary protons, presumably by the (p,p pi /sup +/) reaction. The measurements were made relative to the production of C/sup 11/ activity in polyethylene and polystyrene foils. The production of Be/sup 7/ in the plastic foils was also observed and corresponds to a cross section of 7.7 plus or minus 0.4 mb per carbon nucleus. By comparison of these cross sections with those at lower bombarding energies, no significant trend of the excitation functions is observable. (auth)
Date: August 1, 1962
Creator: Cumming, J.B.; Friedlander, G.; Hudis, J. & Poskanzer, A.M.
Partner: UNT Libraries Government Documents Department

Leaching of accelerator-produced radionuclides

Description: Leaching of radionuclides produced in soil and rock by high energy proton-induced radiation was studied for the SCC and CEBAF sites. Comparison was made with predictions of a Monte-Carlo code CASIM and previous results for the Fermilab site. The principal long-lived radionuclides were {sup 3}H and {sup 22}Na in agreement with Fermilab results. A few other radionuclides were present at lower concentrations in a subset of the samples. For example, {sup 134}Cs was detected in a few SSC water samples and {sup 7}Be and {sup 54}Mn were present at higher concentrations in a CEBAF sample. Leaching from SSC chalk was dependent on previous weathering and on leaching time. The more soil-like marl and shale were leached more rapidly. Results of this study in conjunction with the SSC ground-water model show that adequate ground-water protection would result for loss of the entire proton beam in the SSC Collider tunnel.
Date: May 1, 1994
Creator: Baker, S.; Bull, J. & Goss, D.
Partner: UNT Libraries Government Documents Department

SSCL groundwater model

Description: Activation of groundwater due to accelerator operations has been a consideration since the conceptual stages of the SSC. Prior to site selection, an elementary hydrological model assuming a porous medium with a shallow well in proximity to the tunnel was used to determine the radionuclide concentrations in the water pumped from a well. The model assumed that radionuclides produced within a few feet of the tunnel would migrate to the shallow well and be diluted as the well drew water from a conically symmetric region. After the Ellis County site was selected, the compatibility of this model with the site specific geology was evaluated. The host geology at the selected site is low permeability rock, Austin chalk, shale, and marl, however, vertical fractures do exist. Since the host rock has a low permeability, groundwater in proximity to the tunnel would have to travel primarily through fractures. This hydrology is not compatible with the above mentioned model since water does not percolate uniformly from the surrounding rock into local wells. The amount of dilution of activated water will vary significantly depending on the specific relationship of the well to the activation zone. A further complication in the original model is that it assumes the high energy particles escaping from the accelerator enclosure are localized. The model does not provide for particles being lost over a large area as will happen with routine operational losses. These losses will be distributed along the accelerator over the life of the project. The SSCL groundwater model has been recast to account for the site specific hydrology and both point and distributed losses. Using the new groundwater model, the SSC accelerators are designed to limit the activation concentration in the water located one meter outside the accelerator enclosure to meet the federal drinking water standards. This ...
Date: February 1, 1994
Creator: Romero, V.; Bull, J.; Stapleton, G.; Baker, S.; Goss, D. & Coulson, L.
Partner: UNT Libraries Government Documents Department