Analysis of alpha-particle tracks using CR-39 plastic detectors with optical microscopy and Image Pro-plus software

• Grant number: 05/00797-0
• Support Opportunities: Scholarships in Brazil - Technical Training Program - Technical Training
• Start date: June 01, 2005
• End date: November 30, 2005
• Field of knowledge: Physical Sciences and Mathematics - Physics - Nuclear Physics
• Principal Investigator: Ana Maria Osorio Araya
• Grantee: Ivaldete da Silva Dupim
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

The DETRANES is a group that study the Solid Nuclear Track Detectors for the determination of alfa activity from well waters, indoor radon and the of age samples of apatites and zircon, using the fission track method. The CR-39 plastic detector (Solid Stat Nuclear Track Detector) will use to determine Rn-222. The passage of alfa particle through these detectors leads to the formation of a damage trail which can be obsevable on optic microscopy after a convenient etch. In this case the Cr-39 plastics detectors are placed insid plastic containers outside the water or they are installed in the indoors envirenmental (apartaments and houses). After at around four months these detectors analyzed by the optical microscopy. For the determination of age apatite and zircon we have developed all experimental steps thst lead this mineral to give ages and thermal histiries (collect, separation from hostess rocks, polishing, chemical etching and track analisis). In order to obtain the data, each sample is irradiated with thermal neutron and after irradiation, each sample irradiated and each fraction of the samples, not irradiated are submitted to the etching. The length (confined tracks parallels to the surface of observation) and density measurements are been done under optical microscope at a nominal magnification of 10X100 in oil.