Transmission measurements in air using the ESTRO mini-phantom
(1999) In Physics in Medicine and Biology 44(10). p.2445-2450- Abstract
- The aim of this work is to study the possibility of using the ESTRO mini-phantom for transmission measurements of primary kerma in water at a point free in air. We discuss in-air measurements in general, with special attention given to in-air equivalent measurements using a water equivalent mini-phantom. The study includes four different photon energies (4, 6, 10 and 18 MV), where scoring of dose and primary kerma inside a mini-phantom in narrow beam geometry is performed with the Monte Carlo code EGS4. The results reveal that relative measurements (i.e. with and without a water absorber present) at 10 cm depth in a mini-phantom do not represent the variation of primary kerma in water at a point free in air (deviations as large as 7% at 4... (More)
- The aim of this work is to study the possibility of using the ESTRO mini-phantom for transmission measurements of primary kerma in water at a point free in air. We discuss in-air measurements in general, with special attention given to in-air equivalent measurements using a water equivalent mini-phantom. The study includes four different photon energies (4, 6, 10 and 18 MV), where scoring of dose and primary kerma inside a mini-phantom in narrow beam geometry is performed with the Monte Carlo code EGS4. The results reveal that relative measurements (i.e. with and without a water absorber present) at 10 cm depth in a mini-phantom do not represent the variation of primary kerma in water at a point free in air (deviations as large as 7% at 4 MV are observed). Minimum deviations are obtained at depths somewhat larger than the depth of dose maximum. The observed deviations are due to a considerable beam hardening in the water absorber, which changes the amount of attenuation and scatter inside the mini-phantom. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1114532
- author
- Johnsson, Stefan LU ; Ceberg, Crister LU ; Knöös, Tommy LU and Nilsson, Per LU
- organization
- publishing date
- 1999
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physics in Medicine and Biology
- volume
- 44
- issue
- 10
- pages
- 2445 - 2450
- publisher
- IOP Publishing
- external identifiers
-
- pmid:10533921
- scopus:0032850295
- ISSN
- 1361-6560
- language
- English
- LU publication?
- yes
- id
- b7291190-1f0c-43cf-a572-fceaebb41638 (old id 1114532)
- alternative location
- http://www.iop.org/EJ/article/0031-9155/44/10/306/m91006.pdf
- date added to LUP
- 2016-04-01 12:07:36
- date last changed
- 2022-01-26 23:08:38
@article{b7291190-1f0c-43cf-a572-fceaebb41638, abstract = {{The aim of this work is to study the possibility of using the ESTRO mini-phantom for transmission measurements of primary kerma in water at a point free in air. We discuss in-air measurements in general, with special attention given to in-air equivalent measurements using a water equivalent mini-phantom. The study includes four different photon energies (4, 6, 10 and 18 MV), where scoring of dose and primary kerma inside a mini-phantom in narrow beam geometry is performed with the Monte Carlo code EGS4. The results reveal that relative measurements (i.e. with and without a water absorber present) at 10 cm depth in a mini-phantom do not represent the variation of primary kerma in water at a point free in air (deviations as large as 7% at 4 MV are observed). Minimum deviations are obtained at depths somewhat larger than the depth of dose maximum. The observed deviations are due to a considerable beam hardening in the water absorber, which changes the amount of attenuation and scatter inside the mini-phantom.}}, author = {{Johnsson, Stefan and Ceberg, Crister and Knöös, Tommy and Nilsson, Per}}, issn = {{1361-6560}}, language = {{eng}}, number = {{10}}, pages = {{2445--2450}}, publisher = {{IOP Publishing}}, series = {{Physics in Medicine and Biology}}, title = {{Transmission measurements in air using the ESTRO mini-phantom}}, url = {{http://www.iop.org/EJ/article/0031-9155/44/10/306/m91006.pdf}}, volume = {{44}}, year = {{1999}}, }