Abstract:
:The usefulness of a direct detection scheme of the second harmonic (2h) overmodulated signal from irradiated alanine in EPR dosimetry was studied. For this purpose, a group of DL-alanine/paraffin cylindrical pellets was produced. The dosimeters were irradiated with a 60Co radiotherapy gamma source with doses of 0.05, 0.1, 0.5, 1 and 5 Gy. The EPR measurements were carried out in a VARIAN-E4 spectrometer operating in X-band with optimized parameters to obtain highest amplitude signals of both harmonics. The 2h signal was detected directly at twice the modulation frequency. In preliminary results, the 2h showed some advantages over the 1 h such as better resolution for doses below 1 Gy, better repeatability results and better linear behaviour in the dose range indicated.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Chen F,Graeff CF,Baffa Odoi
10.1088/0031-9155/47/8/309subject
Has Abstractpub_date
2002-04-21 00:00:00pages
1357-67issue
8eissn
0031-9155issn
1361-6560journal_volume
47pub_type
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