Positional radiotherapy beam dosimetry using a laser heated thermoluminescent plate

Journal Article · Tue May 01 00:00:00 EDT 1990 · Medical Physics; (USA)

DOI:https://doi.org/10.1118/1.596580· OSTI ID:6803895

Kearfott, K J ^[1]; Grupen-Shemansky, M E ^[2]

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1. School of Mechanical Engineering Nuclear Engineering and Health Physics Programs, Georgia Institute of Technology, Atlanta, Georgia 30332-0225 (USA)
2. Semiconductor Products Sector, Motorola, Inc., 5005 E. McDowell Road, Phoenix, Arizona (USA)

A 4-W, laser-based system for the positional readout of thermoluminescent (TL) plates was utilized to obtain dose profiles for a {sup 60} Co radiotherapy beam. Experimentally obtained glow curves for LiF resulting from the rapid heating rates characteristic of laser heating agreed well with results predicted using a first-order kinetic model. Excellent system linearity was obtained for sensitivity to {sup 60} Co. The useful dynamic range for this tissue-equivalent system could extend over 8 orders of magnitude. A minimum detectable signal of 1.2 R was estimated for the presently configured system, whose spatial resolution is limited by the laser beam diameter, 1.7 mm. Depth dose profiles for the radiotherapy beam obtained using the prototype laser TL system with a specially designed composite 2.2 cm{times}3.3 cm{times}0.254 mm LiF plate agreed to within 14% of ionization chamber measured doses.

• OSTI ID: 6803895
• Journal Information: Medical Physics; (USA), Vol. 17:3; ISSN 0094-2405
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
GAMMA RADIATION
DEPTH DOSE DISTRIBUTIONS
THERMOLUMINESCENT DOSEMETERS
GLOW CURVE
TISSUE-EQUIVALENT MATERIALS
THERMOLUMINESCENT DOSIMETRY
BEAM POSITION
COBALT 60
GAMMA DOSIMETRY
LASER-RADIATION HEATING
LITHIUM FLUORIDES
PHOTON BEAMS
RADIOTHERAPY
READOUT SYSTEMS
ALKALI METAL COMPOUNDS
BEAMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
COBALT ISOTOPES
DOSEMETERS
DOSIMETRY
ELECTROMAGNETIC RADIATION
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HEATING
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LITHIUM COMPOUNDS
LITHIUM HALIDES
LUMINESCENT DOSEMETERS
MATERIALS
MEASURING INSTRUMENTS
MEDICINE
MINUTES LIVING RADIOISOTOPES
NUCLEAR MEDICINE
NUCLEI
ODD-ODD NUCLEI
PLASMA HEATING
RADIATION DOSE DISTRIBUTIONS
RADIATIONS
RADIOISOTOPES
RADIOLOGY
SPATIAL DOSE DISTRIBUTIONS
THERAPY
YEARS LIVING RADIOISOT
655003* - Medical Physics- Dosimetry