User's manual for PHOEL-2: a Monte Carlo computer code for calculating energies of photoelectrons and Compton electrons in water. [10 to 200 keV; for IBM 360/91]

Technical Report · Wed Aug 01 04:00:00 EDT 1979

DOI:https://doi.org/10.2172/5969565· OSTI ID:5969565

Turner, J. E.; Hamm, R. N.; Wright, H. A.; Modolo, J. T.; Sordi, G. M.A.A.

A Monte Carlo computer code, PHOEL-2, is described for generating the energies of photoelectrons and Compton electrons in water irradiated uniformly by photons having an arbitrary energy spectrum. The code treats input photons individually on the basis of the energy-dependent cross sections for Compton scattering and for the photoelectric effect. Options exist for following each photon through successive Compton scattering events until it disappears by photoelectric absorption or allowing at most only a single Compton scattering event per input photon. The photoelectric effect can be turned on or off with either option. If energetically possible, the photoelectron is assumed to come from the oxygen K shell; otherwise, it originates in the L shell. An Auger electron of energy 0.508 keV is assumed to be emitted following the creation of a K vacancy. The basic numerical data used in PHOEL-2, their mathematical treatment, and the operation of the code are described. Detailed comparisons made with work for /sup 60/Co, and monoenergetic x rays confirm the numerical validity of results obtained with the code. Some of the data of Cormack and Johns are extended by including successive Compton scatterings for the same photon and by including the photoelectric effect and Auger electrons. PHOEL-2 can be obtained from the Radiation Shielding Information Center at Oak Ridge National Laboratory. The new version differs from the old by employing a more realistic handling of the photoelectric cross section as a function of energy, compiling electron spectra instead of storing the energies of every electron produced, eliminating some former input restrictions, and using a different random number generator. PHOEL-2 does not treat pair production, which should be included for water at photon energies above about 2000 keV. 5 figures, 4 tables.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5969565
• Report Number(s): ORNL/TM-6954
• Country of Publication: United States
• Language: English

Related Subjects

654001* -- Radiation & Shielding Physics-- Radiation Physics
Shielding Calculations & Experiments
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABSORPTION
BASIC INTERACTIONS
COMPTON EFFECT
COMPUTER CODES
COMPUTERS
DATA
DATA FORMS
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ENERGY RANGE
ENERGY SPECTRA
FERMIONS
FORTRAN
GAMMA RADIATION
GRAPHS
HYDROGEN COMPOUNDS
IBM COMPUTERS
INFORMATION
INTERACTIONS
IONIZING RADIATIONS
KEV RANGE
KEV RANGE 10-100
KEV RANGE 100-1000
LEPTONS
MOCKUP
MONTE CARLO METHOD
NEUTRAL-PARTICLE TRANSPORT
NUMERICAL DATA
OXYGEN COMPOUNDS
P CODES
PHANTOMS
PHOTOELECTRIC EFFECT
PHOTON TRANSPORT
PROGRAMMING LANGUAGES
RADIATION TRANSPORT
RADIATIONS
SCATTERING
SPECTRA
STRUCTURAL MODELS
THEORETICAL DATA
WATER
X RADIATION