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in subjects: "Dosimetry"

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Optimization of electrochemical-etching parameters for highly sensitive CR-39 fast neutron dosimeters

Voltage gradient and frequency were studied for their influence on the electrochemical etching of CR-39 plastic irradiated with fission spectrum, fast neutrons. A power supply having outputs of up to 1.5 kV (rms) and 5 kHz was used. Differential leakage current measurements under non-etching conditions indicated that the optimal values in electrochemical etching would be 20 kV/cm and 1.3 kHz. That these parameters produced a maximum sensitivity was verified in subsequent electrochemical etching… more

Date: January 1, 1981

Creator: Gammage, R.B. & Chowdhury, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pulsed system for obtaining microdosimetric data with high intensity beams

The use of heavy particle accelerators for radiation therapy requires high intensity beams in order to produce useful dose rates. The 800-MeV proton beam at LAMPF passes through different production targets to generate secondary pion beams. Conventional microdosimetric techniques are not applicable under these conditions because exceedingly high count rates result in detector damage, gas breakdown, and saturation effects in the electronics. We describe a new microdosimetric system developed at … more

Date: January 1, 1977

Creator: Zaider, M.; Dicello, J.F. & Hiebert, R.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron dosimetry of the Little Boy device

Neutron dose rates at several angular locations and at distances out to 0.5 mile have been measured during critical operation of the Little Boy replica. We used modified remmetes and thermoluminescent dosimetry techniques for the measurements. The present status of our analysis is presented including estimates of the neutron-dose-relaxation length in air and the variation of the neutron-to-gamma-ray dose ratio with distance from the replica. These results are preliminary and are subject to dete… more

Date: January 1, 1984

Creator: Pederson, R.A. & Plassmann, E.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Multigroup processing ENDF/B dosimetry covariances

The methodology of multigroup processing of ENDF/B dosimetry covariance (uncertainty) information is discussed, with specific references to the ERRORR covariance module of the NJOY nuclear data processing system. Also discussed is the recent application of ERRORR to the generation of a 137-group, 35-material covariance library for dosimetry applications, and a compact format for storing and transmitting fine-group covariance libraries is introduced.

Date: January 1, 1982

Creator: Muir, D.W.; MacFarlane, R.E. & Boicourt, R.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Energy and technology review, May--June 1991

This issue of Energy and Technology Review describes two powerful analytical tools that use ion-beam techniques to make contributions to an astonishing range of fundamental problems. We characterize these techniques -- accelerator mass spectrometry (AMS) and ion microbeam analysis -- under the common rubric of accelerator microanalysis. Each of these tools is used in disciplines ranging from anthropology to zoology. The rich diversity of applications is reason enough to dedicate an entire issue… more

Date: January 1, 1991

Creator: Johnson, K.C.; de Vore, L.; Gleason, K.; Highstone, H.; Kroopnick, H.; Sanford, N.M. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Calorimetric and ionometric dosimetry for cyclotron produced fast neutrons

A portable tissue equivalent (TE) calorimeter, constructed of A-150 plastic, has been employed for the measurement of absorbed dose in two fast neutron fields produced by the /sup 9/Be(/sup 3/He,n) and /sup 9/Be(d,n) interactions. A disc shaped ionization chamber has also been constructed of A-150 plastic and has a collecting volume geometrically equivalent to the calorimeter core (2 cm in diameter and 0.2 cm thick). A flow of methane compounded TE gas was maintained through the chamber at a ra… more

Date: January 1, 1977

Creator: McDonald, J. C.; Ma, I. C. & Laughlin, J. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A different approach to evaluating health effects from radiation exposure

Absorbed dose D is shown to be a composite variable, the product of the fraction of cells hit (I/sub H/) and the mean /open quotes/dose/close quotes/ (hit size) /ovr z/ to those cells. D is suitable for use with high level (HLE) to radiation and its resulting acute organ effects because, since I/sub H/ = 1.0, D approximates closely enough the mean energy density in the cell as well as in the organ. However, with low-level exposure (LLE) to radiation and its consequent probability of cancer indu… more

Date: January 1, 1988

Creator: Bond, V. P.; Sondhaus, C. A. & Feinendegen, L. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Spectrum unfolding by the least-squares methods

The method of least squares is briefly reviewed, and the conditions under which it may be used are stated. From this analysis, a least-squares approach to the solution of the dosimetry neutron spectrum unfolding problem is introduced. The mathematical solution to this least-squares problem is derived from the general solution. The existence of this solution is analyzed in some detail. A chi/sup 2/-test is derived for the consistency of the input data which does not require the solution to be ob… more

Date: January 1, 1977

Creator: Perey, F.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Uncertainty analysis of dosimetry spectrum unfolding

The propagation of uncertainties in the input data is analyzed for the usual dosimetry unfolding solution. A new formulation of the dosimetry unfolding problem is proposed in which the most likely value of the spectrum is obtained. The relationship of this solution to the usual one is discussed.

Date: January 1, 1977

Creator: Perey, F.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late ef… more

Date: April 1, 1982

Creator: Fabrikant, Jacob I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Damage analysis and fundamental studies. Quarterly progress report, January-March 1980

The DAFS program element is a national effort composed of contributions from a number of National Laboratories and other government laboratories, universities, and industrial laboratories. It was organized by the Materials and Radiation Effects Branch, Office of Fusion Energy, DOE, and a Task Group on Damage Analysis and Fundamental Studies which operates under the auspices of that Branch. The purpose of this series of reports is to provide a working technical record of that effort for the use … more

Date: May 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Considerations in measuring trace radionuclides in soil samples by L x-ray detection

Several aspects pertaining to the measurements of trace radionuclides (such as plutonium) in soil samples by L x-ray detection have been considered. A 3 x 3 multiplexed array of edge-mounted Si detectors with a total detection area of 50 cm/sup 2/ and FWHM resolution of 300 eV at 17 keV has been conceived. The fractional transmission-weighted solid angle for a distributed, self-absorbing source was calculated to be 0.25, which is one half the value of that for a lossless sheet source. To determ… more

Date: Autumn 1977

Creator: Strauss, M. G.; Sherman, I. S.; Swanson, E. J. & Pehl, R. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Specific gamma-ray dose constants for nuclides important to dosimetry and radiological assessment

Tables of specific gamma-ray dose constants (the unshielded gamma-ray dose equivalent rate at 1 m from a point source) have been computed for approximately 500 nuclides important to dosimetry and radiological assessment. The half life, the mean attenuation coefficient, and thickness for a lead shield providing 95% dose equivalent attenuation are also listed.

Date: May 1, 1982

Creator: Unger, L.M. & Trubey, D.K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Transmission factors for the penetration of neutron and photon fluence into wood-frame dwellings, 1990 (TF90)

An earlier study at Oak Ridge calculated radiation doses to persons inside reinforced concrete buildings during the exposure at Nagasaki. The DS86'' study conducted at several laboratories in the United States and Japan concentrated on persons inside wood-frame dwellings at both Nagasaki and Hiroshima. The present study is directed toward applying the general technical approach of the DS86. Numerous simplifications were indicated as a result of the earlier research, and the numerical results ar… more

Date: May 1, 1992

Creator: Rhoades, W. A.; Lillie, R. A. & Emmett, M. B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Damage analysis and fundamental studies. Quarterly progress report, April-June 1980

Date: August 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Some medical aspects of radionuclide intakes

In the field of medicine, particularly industrial medicine, the radiation aspect of the practice probably takes about 1/10 of 1% of our time. All the health physicist's tools of principles of internal dosimetry, lung models, mathematics, chemistry, etc. have little meaning until applied to an individual who has had an intake. This article discusses some of the medical aspects of internal dosimetry.

Date: January 1, 1983

Creator: Poda, G A

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron spectrum measurements using proton recoil proportional counters: results of measurements of leakage spectra for the Little Boy assembly

Measurements of degraded fission-neutron spectra using recoil proportional counters are done routinely for studies involving fast reactor mockups. The same techniques are applicable to measurements of neutron spectra required for personnel dosimetry in fast neutron environments. A brief discussion of current applications of these methods together with the results of a measurement made on the LITTLE BOY assembly at Los Alamos are here described.

Date: January 1, 1984

Creator: Bennett, E.F. & Yule, T.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Technical basis for internal dosimetry at Hanford

The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ({sup 58}Co, {sup 60}Co, {sup 54}Mn, and {sup 59}Fe), strontium, cesium, iodine, … more

Date: July 1, 1991

Creator: Sula, M.J.; Carbaugh, E.H. & Bihl, D.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Pacific Northwest Laboratory annual report for 1981 to the DOE Office of Energy Research. Part 4. Physical sciences. [Lead abstract]

Separate abstracts were prepared for the 13 reports in this 1981 annual report from Battelle Pacific Northwest Laboratory which deals with the physical sciences. (KRM)

Date: February 1, 1982

Creator: Nielsen, J. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Intercomparison of U-238 deposits employed for neutron fluence determination in neutron activation cross section measurements

An intercomparison is made between a collection of five uranium deposits used for neutron fluence determination in neutron activation experiments at Argonne National Laboratory (ANL), Illinois, USA, and a single corresponding deposit from the Institut fuer Radiumforschung und Kernphysik (IRK), Vienna, Austria. The predominant uranium isotope in each of these deposits is U-238. Two methods were used in the study: low-solid-angle alpha counting and the measurement of fast-neutron fission yield ra… more

Date: January 1, 1989

Creator: Meadows, J. W.; Smith, D. L.; Winkler, G.; Vonach, H.; Wagner, M. (Argonne National Lab., IL (USA) & Kernphysik), Vienna Univ. (Austria). Inst. fuer Radiumforschung und

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Accelerator produced nuclides for use in biology and medicine

This bibliography is sorted by subject and by nuclide and also contains an author index. (MHR)

Date: September 1, 1983

Creator: Karlstrom, K.I. & Christman, D.R. (comps.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Computor program for mathematical evaluation of the Rocky Flats nuclear accident dosimetry system

A computer program has been developed to facilitate the evaluation of the Rocky Flats Emergency Dosimetry System. This program evaluates data to determine the neutron fluence associated with a criticality accident. It is necessary to obtain information about the critical system for personnel dose estimates. Information pertaining to the geometry and position of the critical material and orientation of personnel, with respect to the material, is essential to supplement the calculations contained… more

Date: December 20, 1977

Creator: Wood, C. B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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DOSEXPRT: A bioassay dosimetry code for Martin Marietta Energy Systems, Inc

The bioassay code DOSEXPRT was developed for Martin Marietta Energy Systems, Inc., to provide compliance with Department of Energy (DOE) Order 5480, Chapter 11. DOSEXPRT computes the intake of a radionuclide in any year (considering both acute and chronic intakes) from in vivo measurements of the retained activity and/or measurements of the activity in excreta. The committed effective and organ doses for the intake are computed as well as the effective and organ doses expected to be received in… more

Date: April 1, 1992

Creator: Ward, R. C. & Eckerman, K. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Techniques of absolute low energy x-ray calibration

Recent advances in pulsed plasma research, materials science, and astrophysics have required many new diagnostic instruments for use in the low energy x-ray regime. The characterization of these instruments has provided a challenge to instrument designers and provided the momentum to improve x-ray sources and dosimetry techniques. In this paper, the present state-of-the-art in low energy x-ray characterization techniques is reviewed. A summary is given of low energy x-ray generator technology a… more

Date: January 1, 1986

Creator: Day, R.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department