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A new 125I source under the name Braquibac has been developed in Argentina for interstitial brachytherapy applications. The aim of this work is to study the new seed's design and to calculate its dosimetric parameters. Radiographic and destructive tests were carried out on inactive seeds to determine the physical characteristics of the source. Values of g(r), Lambda, F(r, Theta), and phi(an)(r), were obtained in water and air by simulation using the MCNP5 Monte Carlo code according to the methodology recommended in TG-43 and updated in TG-43U1. The dose rate constant was determined to be 0.937+/-0.004 cGy h(-1) U(-1) (overall statistical uncertainty +/-2.7%). Sk per unity activity was calculated to be 0.671+/-0.003 cGy cm2 h(-1) mCi(-1) by simulation of the seed in dry air using point detectors. Spectroscopic studies for both the new and the Amersham model 6711 seed were performed using an HPGe planar detector. The emission spectra of both seeds proved to be very similar. The anisotropy of the total photon intensity in air was measured in planes containing the seed's short and long axes using the HPGe detector. The minimum photon intensity for the new seed was 31.14+/-3.10% of the transverse intensity.

The objective of this study was to characterise thermoluminescent (TLDs) and optically stimulated luminescent dosimeters (OSLDs) at low X-ray energies and estimate the eye lens (DL), thyroid (DT) and mean glandular (DG) doses received during Full-Field Digital Mammography (FFDM) and Digital Breast Tomosynthesis (DBT). The dosimeters were characterised in mammography energies. DL, DT and DG were estimated in FFDM and DBT mode taping dosimeters on the skin of the thyroid gland and on the left eye lens of an Alderson phantom. Dosimeters were also placed on the top of a NORMI PAS phantom simulating a compressed breast. The accuracy, precision and lower limit of detection (LLD) for TLDs and OSLDs were 5 and 8%, 6 and 3%, and 38 and 11 μSv, respectively. The linearity of the kerma response had an R2 > 0.99 and energy dependence was lower than 40%. DT ranged from 0.40 to 2.87 μGy for FFDM and 1.27 to 5.99 μGy for DBT. DG was between 0.50 and 1.27 mGy for FFDM and 1.07 and 1.60 mGy for DBT. DL was below the LLD. Dosimeters showed good performance. DG values were lower than those found in the literature, whereas DT value agreed with references. Differences between DG and DT determined with OSLDs and TLDs were lower than 10% and 200%.