|
KMID : 0378019800230010085
|
|
New Medical Journal
1980 Volume.23 No. 1 p.85 ~ p.90
|
|
|
A Study on Dose Distribution on Co-60 Field with Large Shielding
|
|
|
|
|
Abstract
|
|
|
A Study on Dose Distribution on Co-60 Field with Large Shielding
Wee Saing Kang
Department of Radiology, College of Medicine, Seoul National University Hospital, Seoul, Korea
Percent depth dose and backscatter factor in tissue for Co-6o beam are not constant for such fields that are different in shape even though same in area. In square field A/P= /area/4 but in rectangular field and irregular shaped field we should describe A/P=Cx Varea/4 where C depends on field size and field shape.
If C was known for a given field, A!.P as effective field size could be approximated easily. In comparing Clarkson method and data by measurement, C=0.81 and C=1.09 are obtained respectively for percent depth dose and backscatter factor for L shaped field with shielding larger than quarter of open field.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|