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Author Eappen, K. P. ♦ Mayya, Y. S.
Source IACS Kolkata
Content type Text
Publisher Indian J. Phys.
File Format PDF
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Physics
Subject Keyword Alpha tracks ♦ Radon progeny ♦ SSNTD
Abstract In view of the fact that the radon progeny contribute the highest to thenatural radiation dose to general populations, large scale and long-termmeasurements of radon and its progeny in the houses have been receiving considerableattention. Solid State Nuclear Track Detector (SSNTD) based systems, being the bestsuited for large scale passive monitoring, have been widely used for the radon gas(using a cup closed with a semi-permeable membrane) and to a limited extent, for themeasurement of radon progeny (using bare mode in conjunction with the cup). Thesehave been employed for radon mapping and indoor radon epidemiological studies withgood results. In this technique, alpha tracks recorded on SSNTD films are convertedto radon/thoron concentrations using corresponding conversion factors obtained fromcalibration experiments carried out in controlled environments. The detector response to alpha particles depends mainly on the registrationefficiency of the alpha tracks on the detector films and the subsequent countingefficiency. While the former depends on the exposure design, the latter depends onthe protocols followed for developing and counting of the tracks. The paperdiscusses on parameters like etchant temperature, stirring of the etchant andduration of etching and their influence on the etching rates on LR-115 films.Concept of break down thickness of the SSNTD film in spark counting technique isdiscussed with experimental results. Error estimates on measurement results as afunction of background tracks of the films are also discussed in the paper.
Education Level UG and PG
Learning Resource Type Article
Journal Indian J Phys
Volume Number 83
Issue Number 6
Page Count 7
Starting Page 751
Ending Page 757