Gamma radiation detectors using scintillators continue to be highly relevant in various fields such as the study of radiation in nuclear physics, in environmental radiation measurements, in radiological protection and in industry. The INFISA research group attached to the FCF of the UNMSM, which is located in the Physics Research Institute, has three inorganic solid scintillators of sodium iodide doped with thallium NaI(Tl) with a crystal size of 1.5”x1. 5” (REXON), 2”x2” (TELEDYNE) and 3”x3” (BICRON). In the present work we present the results of the comparison, showing the curves in both efficiency and resolution when characterizing the three scintillators for fine-tuning the detection chain for use in gamma spectroscopy.

Detailed measurements of background radiation in counts per minute (cpm) and dose rates (µSv/h) have been conducted in all the libraries of the National University of San Marcos, located in the University City of Lima, Peru. Radiation measurements were carried out using Geiger-Müller counters to ensure a thorough evaluation of background radiation levels in these educational settings. The results show that the detected radiation levels range between \(14 \pm 1.22\) and \(26 \pm 1.14\) cpm, with an average of \(22 \pm 1.32\) cpm. Additionally, the dose rate values in the libraries range between \(0.16 \pm 0.02\) and \(0.25 \pm 0.03\) \(\mu Sv/h\), with an average of \(0.21 \pm 0.02\) \(\mu Sv/h\). The measurements were conducted in late June and early July 2024, a period of high student concentration due to the proximity of final exams. The facilities of the various libraries span from ...