[Home ] [Archive]    
:: Main :: About :: Current Issue :: Archive :: Search :: Submit :: Contact ::
Main Menu
Home::
IJRR Information::
For Authors::
For Reviewers::
Subscription::
News & Events::
Web Mail::
::
Search in website

Advanced Search
..
Receive site information
Enter your Email in the following box to receive the site news and information.
..
ISSN
Hard Copy 2322-3243
Online 2345-4229
..
Online Submission
Now you can send your articles to IJRR office using the article submission system.
..

AWT IMAGE

AWT IMAGE

:: Volume 5, Issue 1 (6-2007) ::
Int J Radiat Res 2007, 5(1): 45-51 Back to browse issues page
Shielding studies on a total-body neutron activation facility
H. Miri-Hakimabad , H. Panjeh , A. Vejdani-Noghreiyan
, vejdani_ir@yahoo.com
Abstract:   (15238 Views)

Background: Prompt gamma neutron activation analysis (PGNAA) is known as a non-invasive technique capable of measuring elemental concentration in voluminous samples in a short period of time. Also it is a valuable diagnostic tool for total body elemental measurements. 252Cf and 241Am-Be sources which are usually used in this method, generate not only neutrons, but also emit high-energy and unwanted gamma-rays. Because the patient must be located against the neutron source, patient dose during an analysis is an important concern when using this technique.

Materials and Methods: Gamma-rays were attenuated without losing the neutron flux or significant alteration in the neutron spectrum. A relatively safe body chemical composition analyzer was designed with an optimal spherical gamma-ray shield, enclosed to the neutron source. Effects of gamma-ray shielding and optimum radius of spherical Pb shield was investigated and compared with the unfiltered bare source, using MCNP4C code. Then, the gamma ray dose equivalent per source neutron rate (user defined parameter) in the soft tissue is calculated for different radiuses of spherical Pb shield, for both neutron sources.

Results: A decreasing flux of gamma-ray was observed when the radius of the spherical Pb shields increased. The value of this reduction was about 94% for 252Cf source when a lead spherical shield of radius 4 cm was used while the reduction was about 50% for 241Am-Be source with the same spherical shield. For a spherical Pb shield of radius 4 cm, reduction of the gamma dose equivalent per source neutron rate was about 8.44×10-17 Sv when the neutron source was 252Cf and about 1.24×10-16 Sv when the neutron source was 241Am-Be.

Conclusion: Results show using optimum gamma-ray shield geometry can reduce the patient absorbed dose per incident neutron in a body chemical composition analyzer.

Full-Text [PDF 802 kb]   (3710 Downloads)    
Type of Study: Original Research | Subject: Radiation Biology
Send email to the article author

Add your comments about this article
Your username or Email:

CAPTCHA


XML     Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Miri-Hakimabad H, Panjeh H, Vejdani-Noghreiyan A. Shielding studies on a total-body neutron activation facility. Int J Radiat Res 2007; 5 (1) :45-51
URL: http://ijrr.com/article-1-294-en.html


Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Volume 5, Issue 1 (6-2007) Back to browse issues page
International Journal of Radiation Research
Persian site map - English site map - Created in 0.05 seconds with 50 queries by YEKTAWEB 4645