Neutron fluence and energy spectra around the Varian Clinac 2100C/2300C medical accelerator.

Abstract:

:We have simulated the head geometry of a Varian Clinac 2100C/2300C medical accelerator in a Monte Carlo calculation to produce photoneutrons and transport them through the head shielding into a typical therapy room (modeled by a test cell at Varian Associates). The fast neutron leakage fluence and energy spectra have been calculated at 7 positions around the linac head for typical beam operation at 10, 15, 18 and 20 MV. The results of these calculations have been compared with limited measurements made using the same model accelerator operating in a Varian test cell. Calculations were also made for the fluence and energy spectra outside the head with no surrounding concrete walls, floor or ceiling to eliminate the effects of scattering from concrete. Comparisons were also made with calculations using a much simplified head geometry. The results indicate that the calculations using the complex head geometry compare, within the uncertainties, with the measurements. The simple head geometry leads to differences of a factor of 2 from the complex geometry. Results of these calculations can be used to calculate fast neutron transmission through various shielding configurations and through labyrinths.

journal_name

Health Phys

journal_title

Health physics

authors

Kase KR,Mao XS,Nelson WR,Liu JC,Kleck JH,Elsalim M

doi

10.1097/00004032-199801000-00005

subject

Has Abstract

pub_date

1998-01-01 00:00:00

pages

38-47

issue

1

eissn

0017-9078

issn

1538-5159

journal_volume

74

pub_type

杂志文章
  • Ultraviolet response of CaF2:Tm with high-temperature treatment.

    abstract::The thermoluminescent (TL) response to ultraviolet irradiation of CaF2:Tm phosphor is affected by pre-irradiation high-temperature treatment. The experimental results indicate that the maximum intrinsic TL output is about 2000 times higher for 1000 degrees C treatment than when not treated. TL stability for this phosp...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199112000-00017

    authors: Li SH,Hsu PC,Weng PS

    更新日期:1991-12-01 00:00:00

  • Doses to workers in the United States nuclear weapons program due to external irradiation at the dawn of the atomic era (1940-1960).

    abstract::Radiation doses to workers at the Manhattan Engineer District (MED) and Atomic Energy Commission (AEC) sites due to external irradiation during 1940-1960 are reviewed. Categorized radiation dose data were available from AEC annual reports for some years. Annual individual radiation dose data for nine MED/AEC sites for...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199607000-00008

    authors: Strom DJ,Smith MH,Swinth KL,Pettengill HJ

    更新日期:1996-07-01 00:00:00

  • Radiation doses to local populations near nuclear weapons test sites worldwide.

    abstract::Nuclear weapons testing was conducted in the atmosphere at numerous sites worldwide between 1946 and 1980, which resulted in exposures to local populations as a consequence of fallout of radioactive debris. The nuclear tests were conducted by five nations (United States, Soviet Union, United Kingdom, France, and China...

    journal_title:Health physics

    pub_type: 杂志文章,评审

    doi:10.1097/00004032-200205000-00016

    authors: Simon SL,Bouville A

    更新日期:2002-05-01 00:00:00

  • Pasture practices, milk distribution, and consumption in the continental U.S. in the 1950s.

    abstract::Determining the consumption of milk contaminated with 131I, resulting from atmospheric nuclear weapons tests conducted at the Nevada Test Site, by the United States population during the 1950s constitutes one part of the methodology used by the National Cancer Institute to assess radiation exposures to Americans. In o...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199011000-00013

    authors: Dreicer M,Bouville A,Wachholz BW

    更新日期:1990-11-01 00:00:00

  • Chernobyl-derived radiocesium in heather honey and its dependence on deposition patterns.

    abstract::Gamma-ray spectra were measured from Scottish heather honey samples gathered from hive locations with associated airborne gamma-ray survey data. The honeys all contained radiocesium, with activity concentrations ranging from 43-680 Bq kg(-1) 137Cs, and 134Cs/137Cs ratios consistent with Chernobyl deposition. Activity ...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199910000-00011

    authors: Fisk S,Sanderson DC

    更新日期:1999-10-01 00:00:00

  • Non-linear radionuclide transfer from the aquatic environment to fish.

    abstract::Uptake of 226Ra, 232Th, 230Th, and 228Th from water, sediment, and diet sources to bone and muscle of white suckers (Catostomus commersoni) was studied in sixteen lakes in the uranium-mining district of Ontario, Canada. Fish tissues did not increase linearly with environmental concentrations. The best relationship app...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199709000-00007

    authors: Pyle GG,Clulow FV

    更新日期:1997-09-01 00:00:00

  • Navajo birth outcomes in the Shiprock uranium mining area.

    abstract::The role of environmental radiation in the etiology of birth defects, stillbirths, and other adverse outcomes of pregnancy was evaluated for 13,329 Navajos born at the Public Health Service/Indian Health Service Hospital in the Shiprock, NM, uranium mining area (1964-1981). More than 320 kinds of defective congenital ...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199211000-00005

    authors: Shields LM,Wiese WH,Skipper BJ,Charley B,Benally L

    更新日期:1992-11-01 00:00:00

  • Developments in Biodosimetry Methods for Triage With a Focus on X-band Electron Paramagnetic Resonance In Vivo Fingernail Dosimetry.

    abstract::Instrumentation and application methodologies for rapidly and accurately estimating individual ionizing radiation dose are needed for on-site triage in a radiological/nuclear event. One such methodology is an in vivo X-band, electron paramagnetic resonance, physically based dosimetry method to directly measure the rad...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0000000000000874

    authors: Swarts SG,Sidabras JW,Grinberg O,Tipikin DS,Kmiec MM,Petryakov SV,Schreiber W,Wood VA,Williams BB,Flood AB,Swartz HM

    更新日期:2018-07-01 00:00:00

  • A comparison between gross and net count methods when searching for orphan radioactive sources.

    abstract::Different numerical strategies in searching for orphan radioactive sources in the environment by means of a mobile detector system have been evaluated. A carborne 3- by 3-inch NaI(Tl) spectrometric system was used with an unshielded 2 GBq 137Cs source as a test source. In this paper, a previous method (MB method), bas...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-200302000-00008

    authors: Hjerpe T,Samuelsson C

    更新日期:2003-02-01 00:00:00

  • Comparative pathway analysis of radiocesium in the Hudson River Estuary: environmental measurements and regulatory dose assessment models.

    abstract::This work summarizes the measurements and associated environmental dosimetry of reactor-released 137Cs and 134Cs and weapons-produced 137Cs in samples of water, shoreline sediment and fish collected from 1971 to 1980 in the Hudson River Estuary. Trends observed in annual mean concentrations and the resultant dose impl...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-198609000-00003

    authors: Linsalata P,Hickman D,Cohen N

    更新日期:1986-09-01 00:00:00

  • Radon entry into houses: the importance of scale-dependent permeability.

    abstract::Soil permeability to air can increase substantially with measurement length scale. We tested the hypothesis that the scale effect could resolve large model underpredictions of radon and soil-gas entry into two experimental basement structures located in natural sandy-loam soil at a field site in Ben Lomond, CA. Previo...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199908000-00008

    authors: Garbesi K,Robinson AL,Sextro RG,Nazaroff WW

    更新日期:1999-08-01 00:00:00

  • Sorption of 99mTc radiopharmaceutical compounds by soils.

    abstract::Study of the sorption of 99mTc radiopharmaceutical compounds by soils has assessed the fate of these compounds in the event of a surface spill and examined the potential of these compounds as hydrologic tracers. Sorption from deionized water, filtered Missouri River water, and artificial seawater by five surface soils...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/01.hp.0000128583.33124.7d

    authors: Jurisson S,Gawenis J,Landa ER

    更新日期:2004-10-01 00:00:00

  • Ingestion of 226Ra from activated paints on military equipment: transfer factors and doses.

    abstract::The use of 226Ra-activated markings was specific for military equipment some decades ago and the extent of possible internal exposure of former military personnel due to ingestion of 226Ra is an issue of discussion. Whole- or partial-body counts are not sensitive enough to trace an overexposure due to a possible 226Ra...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0b013e3181d18d2e

    authors: Schirmer A

    更新日期:2010-10-01 00:00:00

  • An unrecognized occupancy change in the vicinity of a medical linear accelerator.

    abstract::It seems obvious that if a significant increase in occupancy occurs in the immediate vicinity of any radiation room a reexamination of the adequacy of the shielding should be performed. We discuss a facility where a new building was constructed in close proximity to an existing medical linear accelerator and no consid...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0b013e31823c969b

    authors: Barish RJ

    更新日期:2012-02-01 00:00:00

  • Computational flow and aerosol concentration profiles in lung bifurcations.

    abstract::Flows in lung bifurcations are complicated by geometry, and it is recognized that accurate lung dosimetric models require realistic calculations of the flow and particle deposition patterns. A computational fluid dynamics study of flow and particle concentration has been carried out for a lung bifurcation based on the...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199301000-00002

    authors: Kinsara AA,Tompson RV,Loyalka SK

    更新日期:1993-01-01 00:00:00

  • Effect of contrast material on radiation dose in an adult cardiac dual-energy CT using retrospective ECG-gating.

    abstract::The purpose of this study was to determine the effect of contrast material and retrospective ECG-gating on radiation dose in an adult cardiac dual-energy computed tomography (DECT). Sixty-two patients underwent CT cardiac examination with a Somatom Definition Flash DECT using tube voltages of 100 kV without filter and...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0b013e31828d814c

    authors: Paul J,Jacobi V,Bazrafshan B,Farshid P,Vogl T

    更新日期:2013-08-01 00:00:00

  • Lauriston S. Taylor Lecture on radiation protection and measurements: what makes particle radiation so effective?

    abstract::The scientific basis for the physical and biological effectiveness of particle radiations has emerged from many decades of meticulous basic research. A diverse array of biologically relevant consequences at the molecular, cellular, tissue, and organism level have been reported, but what are the key processes and mecha...

    journal_title:Health physics

    pub_type:

    doi:10.1097/HP.0b013e31826a5b85

    authors: Blakely EA

    更新日期:2012-11-01 00:00:00

  • Determination of Uranium Series Activity Before Secular Equilibrium Is Established.

    abstract::Timely achievement of uranium series' secular equilibrium is not always feasible. Our objective is to mathematically justify methods for early uranium series gamma spectroscopy measurements that can accurately predict naturally occurring radioactive material equilibrium activities long before equilibrium is establishe...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0000000000001073

    authors: Wilson CA 4th,Matthews KL 2nd,Hamideh AM,Wang WH

    更新日期:2019-10-01 00:00:00

  • A Monte Carlo approach to assessing 147Pm in the liver of the adult phantom.

    abstract::A low-background phoswich detector is used to detect small amounts of 147Pm--a pure beta-emitting nuclide--present in the liver of an occupational worker. The assessment was based on the measurement of bremsstrahlung radiation produced by the beta particles in the tissue. Computer programs based on Monte Carlo techniq...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199306000-00010

    authors: Bhati S

    更新日期:1993-06-01 00:00:00

  • What views and uses of radiation sources in the 21st century?

    abstract::Considering that in 1899 neither biotechnology nor the electronic revolution were foreseen, some humility might be advisable when one looks into the crystal ball for the future role of radiation sources. In the past 50 years, nuclear medicine, nuclear weapons, and nuclear power have had a huge impact in the world. In ...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-200104000-00008

    authors: Blix H

    更新日期:2001-04-01 00:00:00

  • Radon calibration chamber assembly, detector accuracy, and pertinent operational findings.

    abstract::Reliable radon laboratory operations motivated the construction of three radon gas calibration chambers. One chamber is used for background calibrations while the other two cover a radon gas concentration range of 110 to >5,550 Bq m(-3) (3-150 pCi L(-1)). The chambers entered commercial service, for tertiary radon cal...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/01.HP.0000267006.55621.2f

    authors: Distenfeld CH

    更新日期:2007-08-01 00:00:00

  • Emergency care centers--an efficient method for mitigation of consequences after a dirty bomb attack.

    abstract::For emergency preparedness and response with respect to nuclear power plant accidents, the concept of Emergency Care Centers has been developed in Germany. This setup aims at monitoring contamination, to decontaminate if needed, assess the dose, and perform an initial medical evaluation of people who might have been a...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0b013e31824765c3

    authors: Miska H

    更新日期:2012-08-01 00:00:00

  • Utilizing K-12 school and higher education programs to incorporate homeland security topics for public education.

    abstract::The broad based mission statements of public institutions whose charters are to educate the public is analyzed so that common threads pertinent to homeland security action items can be correlated with the public education scope. The intent of the coordination is to ensure that the prevention component in addition to t...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-200308001-00013

    authors: McCarthy ME

    更新日期:2003-08-01 00:00:00

  • Modeling population screening process for maximizing throughputs.

    abstract::Following a large-scale radiation emergency, affected populations will need to be screened soon after for potential contamination (external or internal). Effective management of the available resources can help maximize the screening throughputs. This paper reports the modeling results for screening throughputs in a p...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/HP.0000000000000114

    authors: Li C,Capello K,Jeng HA,Hauck B,Kramer GH

    更新日期:2014-05-01 00:00:00

  • Fifty years of plutonium exposure to the Manhattan Project plutonium workers: an update.

    abstract::Twenty-six white male workers who did the original plutonium research and development work at Los Alamos have been examined periodically over the past 50 y to identify possible health effects from internal plutonium depositions. Their effective doses range from 0.1 to 7.2 Sv with a median value of 1.25 Sv. As of the e...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199710000-00004

    authors: Voelz GL,Lawrence JN,Johnson ER

    更新日期:1997-10-01 00:00:00

  • Spatial and temporal distribution of energy.

    abstract::Studies of the spatial and temporal distribution of microscopic radiation doses lead to potentially important questions regarding conventional approaches to radiation protection. The short ranges of alpha-particle and Auger-electron emissions from radionuclides lead to uncertainties in assessing their hazards. The con...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-198808000-00015

    authors: Goodhead DT

    更新日期:1988-08-01 00:00:00

  • Radionuclides in the terrestrial ecosystem near a Canadian uranium mill--Part I: Distribution and doses.

    abstract::Soils, vegetation, small mammals, and birds were measured for uranium series radionuclides at three sites near the operating Key Lake uranium mill in northern Saskatchewan. Sites, impacted by windblown tailings and mill dust, had significantly higher concentrations of uranium, 226Ra, 210Pb, and 210Po in soils, litter,...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-200006000-00003

    authors: Thomas PA

    更新日期:2000-06-01 00:00:00

  • Calculation of absorbed energy in the gastrointestinal tract.

    abstract::One goal of this research was to reproduce the photon specific absorbed fraction calculations of Cristy and Eckerman using their gastrointestinal (GI) tract model. A second goal was to calculate photon specific absorbed fraction values for their GI tract model using electron tracking techniques. A final goal was to ca...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/00004032-199609000-00005

    authors: Poston JW Jr,Kodimer KA,Bolch WE,Poston JW Sr

    更新日期:1996-09-01 00:00:00

  • Radiofrequency exposure from wireless LANs utilizing Wi-Fi technology.

    abstract::This survey measured radiofrequency (RF) fields from wireless local area networks (WLANs) using Wi-Fi technology against a background of RF fields in the environment over the frequency range 75 MHz-3 GHz. A total of 356 measurements were conducted at 55 sites (including private residences, commercial spaces, health ca...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/01.HP.0000248117.74843.34

    authors: Foster KR

    更新日期:2007-03-01 00:00:00

  • Uncertainties analysis of doses resulting from chronic inhalation of plutonium at the Mayak production association.

    abstract::A method is presented to determine the uncertainties in the reported dose due to incorporated plutonium for the Mayak Worker Cohort. The methodology includes errors generated by both detection methods and modeling methods. To accomplish the task, the method includes classical statistics, Monte Carlo, perturbation, and...

    journal_title:Health physics

    pub_type: 杂志文章

    doi:10.1097/01.hp.0000154027.92466.97

    authors: Krahenbuhl MP,Bess JD,Wilde JL,Vostrotin VV,Suslova KG,Khokhryakov VF,Slaughter DM,Miller SC

    更新日期:2005-07-01 00:00:00