[en] The design and construction of very low frequencies electronic filters which will be used for carrying out analysis of pile noise at Mexico's Nuclear Center Triga Mark III Reactor, in order to realize measurements of its parameters is presented. NIM norms and active filters with lineal integrated circuits were used: a. Band pass filter from 10 to 500 hertz, band width <= 1 Hz. 11 steps with Q>50. b. Low pass filter from 0.001 to 10 hertz in 3 steps. c. Kalman Bucy filter, an analogical simulation of this filter was undertaken, obtained from a mathematical model of a Zero power experimental reactor, with the purpose to establish a control searching. (author)

No abstract available

[en] We describe the experiments realized in order to probe the response of the alpha particles detectors manufactured in our laboratory and their suitability to some important applications. The detection system is a nitrocellulose film which register the transit of the charged particles. The traces left by the particles during their transit are manifested through a controlled chemical attack and counted after that with a microscope. This monitor system was utilized in the following applications: 1) uranium prospection 2) alpha autoradiography 4) determination of air pollution by alpha emitters. The results which were obtained are satisfactory and in spite that in these first applications only qualitative measurements were made the method could be used for quantitative determinations when we will have a better knowledge of the effect of factors which are not under our control. (author)

[en] In this work the obtained results to synthesize thin films of amorphous carbon with incorporated nitrogen and hydrogen are presented, as well as thin films of aluminium oxide using the laser ablation technique. The thin films were exposed to ionizing radiation (gamma rays of a ⁶⁰ Co source, beta radiation of a ⁹⁰ Sr source) and a non-ionizing radiation (UV radiation). The obtained results show that it is possible to obtain materials in thin film form with thickness of hundreds of nanometers, which present thermoluminescent response when being irradiated with ionizing radiation and non-ionizing radiation. (Author)

[en] We describe the pilot quality control program for brachytherapy of low dose rate proposed to be used in the Radiotherapy Department at the General Hospital of Mexico. The program consists of three parts: a) development of calibration procedures, performed in terms of air-kerma strength for calibration of 137Cs and 192Ir brachytherapy sources, and for the calibration of well-type ionization chambers for 137Cs, b) performance of localisation and reconstruction techniques for radioactive sources with a Baltas' phantom. The results obtained for the media deviation , are in the optimum level, ± 0.5 mm < ± 1.0 mm; the confidence limit Δ, is in the emergency level, Δ=3.2 mm. c) verification of absorbed dose to water DW, given by the hospital. It consists on the characterisation of a TLD-100 powder dosimetry system at SSDL: The calibration curves for powder response (nC or nC/ mg) vs Dw and the control charts for the Harshaw 3500 reader were obtained. The statistical validation of the calibration curve by normality of the residuals and the lack of fit tests were realised. In the other hand, TLD's were irradiated in the hospital to a nominal Dw = 2 Gy with sources of 137Cs. The percent deviations Δ%, between the Dw imparted by the Hospital and the determined by SSDL, are 1.2% Δ≤ 6.5 % which are consistent with the expanded uncertainty U% for DW, 5.6 U% 10%

[en] The verification consists on the planning and administration of stereotactic treatments by means of conformed static beams, several polyethylene capsules with powder TLD 100 (type IAEA) located inside the head of a phantom Alderson-Rando. Because the planning system corrects for no-homogeneity in the density from the tomographic information, it is assumed that the absorbed dose in the tumor volume (capsule) corresponds to the dose absorbed to LiF: DLiF. Applying different cavity theories, the percent deviations to the nominal dose are: -1.81%≤Δ%≤0.71%, which are consistent with the order of the U%'s. The values of DW are calculated from two calibration curve: TL Response (nC) vs DW for the energy of the 60Co corrected for energy dependence to the accelerator photon beam quality D20/D10=0.57. Once curve for 0.5 to 5 Gy and other for 5 to 35 Gy. The traceability for the Dwater is obtained by means of a secondary standard ionization chamber Farmer PTW 30013 calibrated at the NRC