Author/Editor		el-Khatib, EE; Podgoršak, EB; Pla, C
Title		Broad beam and narrow beam attenuation in Lipowitz's metal
Type		članek
Source		Med Phys
Vol. and No.		Letnik 14, št. 1
Publication year		1987
Volume		str. 135-9
Language		eng
Abstract		Attenuation properties of Lipowitz's metal have been studied for narrow and broad beams of cobalt-60 gamma rays and 4-10 MV x-rays. The measured transmitted fraction for geometries used in radiotherapy depends on the field size and depth of measurement. Therefore a calculation of dose for partially attenuated beams based on narrow beam attenuation coefficients can cause large errors in dosimetry. Our simple calculation of transmitted fractions based on primary attenuation and scattered radiation agrees quite well with the measured data for therapeutic geometries. Also given is a table for linear, mass attenuation, and mass energy absorption coefficients of Lipowitz's metal in the photon energy range from 10 keV to 10 MeV.
Descriptors		ALLOYS RADIATION PROTECTION BIOPHYSICS MODELS, ANATOMIC RADIOTHERAPY DOSAGE RADIOTHERAPY, HIGH-ENERGY