Abstract:
:A special parallel-plate ionization chamber was developed. The motivation for the construction of this new chamber was mainly to fulfil the need of a reference system for computed tomography standard beams in the Calibration Laboratory of IPEN. However, the chamber was tested also in standard radiation beams of mammography and conventional diagnostic radiology. The chamber was manufactured at the institute workshop, as simply and cheaply as possible. Its design differs from the common ionization chambers used in dosimetric procedures of computed tomography equipment, because it is a parallel-plate chamber instead of a cylindrical chamber. However, its dimensions and sensitive volume are very similar to those of a commercial pencil ionization chamber. The new ionization chamber was submitted to several characterization and quality control tests, showing its very good performance.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Maia AF,Caldas LVdoi
10.1088/0031-9155/50/16/012subject
Has Abstractpub_date
2005-08-21 00:00:00pages
3837-47issue
16eissn
0031-9155issn
1361-6560pii
S0031-9155(05)97185-6journal_volume
50pub_type
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