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Measurements of output factors for small photon fields up to 10 cm x 10 cm

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Date Issued:
2013
Summary:
Field output factors (OF) for photon beams from a 6 MV medical accelerator were measured using five different detectors in a scanning water phantom. The measurements were taken for square field sizes of integral widths ranging from 1 cm to 10 cm for two reference source-to-surface distances (SSD) and depths in water. For the diode detectors, square field widths as small as 2.5 mm were also studied. The photon beams were collimated by using either the jaws or the multileaf collimators. Measured OFs are found to depend upon the field size, SSD, depth and also upon the type of beam collimation, size and type of detector used. For field sizes larger than 3 cm x 3 cm, the OF measurements agree to within 1% or less. The largest variation in OF occurs for jawsshaped field of size 1 cm x 1cm, where a difference of more than 18% is observed.
Title: Measurements of output factors for small photon fields up to 10 cm x 10 cm.
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Name(s): Bacala, Angelina, author
Pella, Silvia, Thesis advisor
Charles E. Schmidt College of Science, Degree grantor
Department of Physics
Type of Resource: text
Genre: Electronic Thesis Or Dissertation
Issuance: single unit
Date Created: Fall 2013
Date Issued: 2013
Publisher: Florida Atlantic University
Physical Form: Online Resource
Extent: 78 p.
Language(s): English
Summary: Field output factors (OF) for photon beams from a 6 MV medical accelerator were measured using five different detectors in a scanning water phantom. The measurements were taken for square field sizes of integral widths ranging from 1 cm to 10 cm for two reference source-to-surface distances (SSD) and depths in water. For the diode detectors, square field widths as small as 2.5 mm were also studied. The photon beams were collimated by using either the jaws or the multileaf collimators. Measured OFs are found to depend upon the field size, SSD, depth and also upon the type of beam collimation, size and type of detector used. For field sizes larger than 3 cm x 3 cm, the OF measurements agree to within 1% or less. The largest variation in OF occurs for jawsshaped field of size 1 cm x 1cm, where a difference of more than 18% is observed.
Identifier: FA0004003 (IID)
Note(s): Includes bibliography.
Thesis (M.S.)--Florida Atlantic University, 2013.
Subject(s): Integrated circuits
Photonics
Quantum electrodynamics
Quantum theory
Held by: Florida Atlantic University Digital Library
Sublocation: Boca Raton, Fla.
Persistent Link to This Record: http://purl.flvc.org/fau/fd/FA0004003
Restrictions on Access: All rights reserved by the source institution
Restrictions on Access: http://rightsstatements.org/vocab/InC/1.0/
Host Institution: FAU