Estimation Method for Alpha Particle Counting Efficiency for Scintillation Flasks (original) (raw)
1997, Radiation Protection Dosimetry
Fluence-to-absorbed dose conversion coefficients and their variations with angle of incidence have been computed for monoenergetic beams of electrons incident on rod and pillar ICRU-tissue phantoms used for calibration of ring and wrist or ankle dosemeters for measurement of personal dose equivalent to the skin. Beams are normal to the axes of the cylindrical phantoms. For normally incident electrons, conversion coefficients for both the rod and pillar phantoms are equal to those for the slab phantom. However, they differ markedly from each other and from those for the slab phantom at electron angles of incidence as great as 90°, as measured between the beam direction and an inward directed radius through a dose point at distance 0.007 cm beneath the surface of the phantom. * By mass, 76.2% oxygen, 11.1% carbon, 10.1% hydrogen, and 2.6% nitrogen (1) .
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