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In this study, the concentrations of uranium for four species of plants; Spinacia, Brassica Oleracea, BEASSICA Oleracea Var Capitata and Beta Vulgaris were measured in addition to the measurement of uranium concentrations in the selected soil by calculating the number of significant traces of alpha in CR-39. The 2.455 Bq/kg in Spinacia plant were the highest concentration while the lowest concentration of uranium were 1.91 Bq/kg in BEASSICA Oleracea Var Capitata plant. As for the transfer factor, the highest value 0.416 were found in Spinacia plant and the lowest value 0.323 were found in BEASSICA Oleracea Var Capitata plant. The uranium in the models studied in it did not exceed the international limit, according to the International Atomic Energy Agency.

HIPSTER (Heavily Ionising Particle Standard Toolkit for Event Recognition) is an open source Python package designed to facilitate the use of TensorFlow in a high energy physics analysis context. The core functionality of the software is presented, with images from the MoEDAL experiment Nuclear Track Detectors (NTDs) serving as an example dataset. Convolutional neural networks are selected as the classification algorithm for this dataset and the process of training a variety of models with different hyper-parameters is detailed. Next the results are shown for the MoEDAL problem demonstrating the rich information output by HIPSTER that enables the user to probe the performance of their model in detail., 8 pages, 5 figures, contribution to CHEP 2018 conference

Radon concentrations in different sources of water samples collected from five different regions of Egypt by alpha track dosimetry using LR-115 detectors were determined. The values of radon concentration in water samples did not exceed the maximum level of contamination of 11 BqL−1 reported by the US Environmental Protection Agency and the recommended level of 10 BqL−1 by UNSCEAR 2000. The calculated values of annual effective dose for adults, children, and infants from radon ingested are less than the reference level of 100 μSvy−1 as recommended by the International Atomic Energy Agency, 2002 and WHO, 2009. From these results, it is concluded that there is no radiological risk related to radon ingested from the water samples analyzed in the study area of five different regions of Egypt.

Radon is an inert radioactive gas. A long term exposure to high concentration of radon causes lung cancer. Taking this into account, an investigation in some offices of Adigrat Universityhas been made to estimate the radon concentrations and to determine the health risk of the workers in the community. In the present study, Solid State Nuclear Track Detectors (LR-115 type II) has been used to measure the emission of radon from 12 offices for a period of 3 months. After an exposure time of 3 months, films were removed from each office andtaken for etching. After the etching, films were washed with distilled water and allowed to dry for 1day. Finally, alpha tracks were counted using an optical microscope at magnification power of 400X. Results obtained in the present study show that the value of concentration of radon ranges from 171.31 Bq.m−3 to 394.05 Bq.m−3 with mean concentration273.79 Bq.m−3 and standard deviation of 79.7Bq.m−3 and the inhalation dose rate varies from a minimum of 1.54 mSv.y−1 to a maximum of 3.55 mSv.y−1 with an average of 2.46 mSv.y−1 and standard deviation of 0.72 mSv.y−1. Even though, radon concentration levels were found to be higher the inhalation dose rate is safe within recommended limits

In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range.

In this study, radon and thoron concentrations in soil gas has been monitored using LR-115(II) solid state nuclear track detectors since 15th July 2011 to February 2012. The study was carried out along Mat fault in Serchip district, Mizoram, India at two different sites – Mat Bridge (23°18′N, 92°48′E) and Tuichang (23°13′N, 92°56′E). The results obtained have been correlated to the seismic events that occurred within 800 km from the measuring sites over the mentioned period of time. Anomalous behaviour in radon concentrations have been observed prior to some earthquakes. Interestingly, some thoron anomalies were also recorded.

Makrofol DE1-4C detectors were exposed to fission fragments and alpha particles (of energy 0.5–3 MeV) from a 252Cf source in a vacuum chamber. The exposed detectors were etched in 6-N NaOH solution at 70 °C to measure etch induction times. An optical microscope was used to investigate various charged particle tracks and diameters in Makrofol detectors. The etch induction times for alpha-particle and fission-fragment tracks were obtained from the intersections of extrapolations of a graph of track diameters with time. The obtained results will be very useful in nuclear track studies, as well as nanotechnology fields.

An extensive studies on the indoor activity concentrations of thoron, radon and their progeny in the granite region in the state of Karnataka, India, has been carried out since, 2007 in the scope of a lung cancer epidemiological study using solid-state nuclear track detector-based double-chamber dosemeters (LR-115, type II plastic track detector). Seventy-four dwellings of different types were selected for the measurement. The dosemeters containing SSNTD detectors were fixed 2 m above the floor. After an exposure time of 3 months (90 d), films were etched to reveal tracks. From the track density, the concentrations of radon and thoron were evaluated. The value of the indoor concentration of thoron and radon in the study area varies from 16 to 170 Bq m(-3) and 18 to 300 Bq m(-3) with medians of 66 and 82.3 Bq m(-3), respectively, and that of their progeny varies from 1.8 to 24 mWL with a median of 3.6 mWL and 1.6 to 19.6 mWL, respectively. The concentrations of indoor thoron, radon and their progeny and their equivalent effective doses are discussed.

Western part of Turkey is rich area in terms of geothermal sources. The one of these geothermal areas is Bayindir-Derekoy/Ergenli located in Kucuk Menderes Graben. In this study, indoor radon concentrations were determined in some places (spas and some dwellings) located on Bayindir-Derekoy/Ergenli. Measurements were realized using LR-115 type 2 solid state nuclear track detectors in the course of 10 months. The indoor radon concentrations were found between 39.3 and 235.4 Bq m−3 for spas, 39.3 and 405 Bq m−3 for houses. Indoor radon concentrations were compared with reference levels determined by international agencies. Radon concentrations in this area were quite low than reference levels revised by international health agencies.

Alpha and beta activities per unit volume of air, due to radon, thoron and their decay products were measured in the outdoor atmosphere in Errachidia city, Morocco, by using both CR-39 and LR-115 type II solid-state nuclear track detectors (SSNTDs). Simultaneously, meteorological parameters such as air temperature, atmospheric pressure, and relative humidity were also measured in situ.. In addition, the outdoor radon activities show the highest value of the outdoor radon activity was determined in the early morning hours, and the lowest values were found in the afternoon, over a three month study period, between April-June 2006. The diurnal variations in the outdoor radon activity are found to exhibit correlation with relative humidity and negatively correlate with the air temperature. The annual effective dose in the present study for Errachidia environment is found to be 0.29 mSv/y.

In general people associate environmental radioactivity with the artificial radioactivity and knows very little about natural radioactivity. Thus there is a critical need to improve nuclear physics public education. From 2005 in Italy two programs were promoted from Ministry of Education and University and National Institute of Nuclear Physics (INFN) for scientific dissemination in the field of environmental radioactivity. High school students in many Italian regions were involved in particular in indoor radon measurements. With this program students acquired awareness about the risks of inhalation of radon and its progeny and at the same time contributed to carry out radon monitoring, participating to all the experimental phases, from detectors set-up to data analysis. In particular we report about the activities carried out at Catania University and INFN division regarding a survey in the eastern Sicily. The overall monitoring, spanned over a period of 5 years, was carried out using passive nuclear track detection technique, through CR-39 dosimeters. In total about 500 detectors were placed in dwellings and schools in 57 locations. The investigated area have shown medium–high indoor radon concentrations, higher than the Italian average (70 Bq/m3). From the evaluation of the participating teachers and students, this kind of activities represents a successful strategy to enhance dissemination of physics, in particular in radioactivity topics.

The paper presents results of radon (222Rn) and thoron (220Rn) levels in different parts of some selected plants used in Moroccan cooking and traditional medicine. Plant uptake of radionuclide is one of many vectors for introduction of contaminants into the human food chain. Thus, it is critical to understand the soil–plant relationships that control nuclide bioavailability. The radon and thoron concentrations have been determined in the studied samples and their corresponding soils, and that using the technique based on two types of solid state nuclear track detectors (SSNTDs) LR-115 type-II and CR-39. Transfer factors (TF) of 222Rn and 220Rn from soil to parts of various studied plants have been determined. TF for roots were higher than those for stems and leaves. The radon and thoron activities in the soils have been found varying from 0.87 0.06Bq.kg-1 to 6.20 0.47Bq.kg-1 and from 30 2.30mBq.kg-1 to 195±16mBq.kg-1, respectively. These values are lower in the leaves and stems than those determined in the roots of the studied plants. The aim of this study was to analyze the radon transfer from soil to different compartments of these plants and then to evaluate the radiotoxicity caused by radon in order to contribute to the health risk assessment.

Track counting algorithms as one of the fundamental principles of nuclear science have been emphasized in the recent years. Accurate measurement of nuclear tracks on solid-state nuclear track detectors is the aim of track counting systems. Commonly track counting systems comprise a hardware system for the task of imaging and software for analysing the track images. In this paper, a track recognition algorithm based on 12 defined textual and shape-based features and a neuro-fuzzy classifier is proposed. Features are defined so as to discern the tracks from the background and small objects. Then, according to the defined features, tracks are detected using a trained neuro-fuzzy system. Features and the classifier are finally validated via 100 Alpha track images and 40 training samples. It is shown that principle textual and shape-based features concomitantly yield a high rate of track detection compared with the single-feature based methods.

A series of atomic force microscopy (AFM) images of etched nuclear tracks has been obtained and used to calculate the nuclear track registration sensitivity parameter V(x) = Vt(x)/Vb. Due to the AFM limitations the samples were irradiated normally to the surface, and with energies attenuated in order to include the Bragg peak region in the AFM piezo-scanner z movement range. The simulation of the track profile evolution was then obtained. The different stages of etched nuclear track profiles were rendered.

The microscopic process taking place during chemical etching is described in terms of a dynamic framework governed by capillary condensation. The aim is to obtain physical information on how the cone shaped tracks with curved walls evolve during chemical etching under a close examination of first principles. The results obtained with the proposed theory are compared with published values to establish their range of validity.

In Spain, a recent modification in the regulations of protection against ionizing radiation obligates to determine radon levels in particular workplaces like spas, mines and caves. Most of these workplaces may present extreme measurement conditions like high aerosol content, temperature, and humidity that can affect the radon detector response. In our laboratory we use to determine mean radon activity concentration in air with the nuclear track detector Makrofol DE covered with an aluminized Mylar foil and placed within the FzK FN diffusion chamber with a glass fibre filter. We have compared detector response using different filter configurations in common laboratory ambient conditions. The configuration with a better response (polyethylene filter) and our reference configuration took part in a study of the effect of different temperature and humidity on our detector response carried out in the INTE radon chamber. Results obtained did not show a significant difference between detector responses with both filters. However, when we exposed them for long periods to real environmental conditions at underground sites we could observe Mylar deterioration. To look in detail into a possible effect of long-term high-humidity exposures we exposed nine sets of detectors with three different polyethylene bags, first five sets under controlled conditions in the INTE radon chamber and then four sets in long-term exposures at high humidity environments. We have seen that the Mylar foil can be damaged depending on the duration of exposure. In a radon chamber exposure time is normally limited to a few days for practical and financial reasons; therefore, results do not show if humidity affects the glass fibre filter and detectors response. To analyse it we exposed detectors in a real humid environment up to a month where we already observed Mylar deterioration due to humidity but the possible impact on track density is hidden by the scattering of the results found, so a clear conclusion cannot be stated.

In the present study the dependence of both the bulk etch rate for Solid state nuclear track detectors (SSNTD) on etching time and the removal thickness percentage on etchant concentration of the NaOH solution and etching time have been studied for CR-39 detector irradiated with 0, 10, 50 and 100 (kGy) γ-ray. The dependence of track density on the etchant concentration of NaOH solution for CR-39 samples irradiated with doses of 0, 10, 50 and 100 (kGy) γ-ray at constant etching time has also been studied. The damage on the samples surface due to irradiation with different γ-dose was determined and noticed with electronic microscope.

Alpha Track Analysis (ATA) technique is one of the most sensitive tools for revealing the μ -distribution of the trace amounts of α -emitting radionuclides through the contaminated samples. The identification of radionuclides using solid state nuclear track detectors (SSNTD) along with the α -activity determination in the case of non-planar preparation is beyond the limits of the conventional ATA. In the current paper the comprehensive analytic system for recognition and processing of etched α -tracks in CR-39 plastic nuclear track detector (TASTRAK, Bristol) is presented. The considerable advantage of the proposed algorithm for α -track image analysis is the opportunity to separate the overlapping α -tracks and the α -tracks with the imperfect contours by fitting object templates to edge fragments of the probe image.

The aim of this paper is to provide an overview of the developments in nuclear track methodology as published in the proceedings of the last ten meetings of the International Conference on Nuclear Tracks in Solids (ICNTS) from the Marburg (Germany) conference in 1990 to the Bologna (Italy) conference of 2008. Nuclear Tracks Methodology (NTM) examines the effects of the interaction between charged particles and solid materials and presents several desirable characteristics: the detectors can easily be cut into a size appropriate for any application and can be used in locations for which other radiation detectors are not suitable; the etching and reading instrumentation is relatively simple; there is a quasiinsensibility to gamma radiation for reasonable dose exposures (typically

In the present work, it is demonstrated the first application of cellular automata to the growing of etched nuclear tracks. The simplest case in which conical etched tracks are gradually formed is presented, as well as a general case of time varying etching rate V t . It is demonstrated that the cellular automata elements consist in an image pattern of the latent nuclear track input cells, 16 rules for updating states, the Moore neighborhood and an algorithm of four states.

Radon represents the most important contribution of population exposure to natural ionising radiation. This article presents the first indoor radon map in some regions of Romania based on 883 surveyed buildings in the Ştei-BăiŢa radon-prone region and 864 in other regions of Romania. Indoor radon measurements were performed in the last 10 y by using CR-39 nuclear track detectors exposed for 3-12 months on ground floor levels of dwellings. Excluding the Ştei-BăiŢa radon-prone region, an average indoor radon concentration of 126 Bq m(-3) was calculated for Romanian houses. In the Ştei-BăiŢa radon-prone area, the average indoor concentration was 292 Bq m(-3). About 21 % of the investigated dwellings in the Ştei-BăiŢa radon-prone region exceed the threshold of 400 Bq m(-3), while 5 % of the dwellings in other areas of Romania exceed the same threshold. As expected, indoor radon concentration is not uniformly distributed throughout Romania. The map shows a high variability among surveyed regions, mainly due to the differences in geology. The radon emanation rate is substantially influenced by the soil characteristics, such as the soil permeability and soil gas radon concentration. Since higher permeability enables the increased migration of soil gas and radon from the soil into the building, elevated levels of indoor radon can be expected in more permeable soil environments.

Indoor radon level measurements were carried out in 42 dwellings in Bethlehem, Palestine, using CR-39 solid state nuclear track detectors. The measurements were performed during winter and spring seasons of the year 2010, for a period ranging from 97-118 d using a total of 100 detectors. The detectors were installed in living rooms, bedrooms, kitchens, and storage areas of 39 houses, as well as in three schools, selected randomly in the surveyed area. The results of indoor radon levels and the annual effective dose in houses were found to vary from 26 - 611 Bq m(-3) and 0.65 - 14.1 m Sv y(-1), with average values of 117.0 Bq m(-3) and 2.95 m Sv y(-1), respectively. The mean values of radon concentration levels in bedrooms, kitchens, living rooms, basements, and storage areas are, respectively, 106.5, 113.1, 101.5, and 164.2 Bq m(-3). The corresponding mean values of annual effective dose for the bedrooms, kitchens, living rooms, basements, and storage areas are 2.66, 2.83, 2.54, 14.1 m Sv y(-1), respectively. In schools, the radon levels are found to vary from 31 - 400 Bq m(-3) with an average value of 125.1 Bq m(-3). The average annual effective dose in schools is found to be 3.12 mSv y(-1). This value is higher than the assigned international value. In general, the results show that radon concentration levels in 83% of the investigated dwellings are lower than the indoor radon action level of 150 Bq m(-3) for the United States.

Radon concentration levels were measured in the soil and indoors of Jerash city using time-integrated passive radon dosimeters enclosing CR-39 solid-state nuclear track detectors (SSNTDs). The city was divided into five sectors over which four hundred dosimeters were distributed randomly; one hundred dosimeters were installed into soil and the rest were distributed indoors. The study revealed that radon concentration in soil ranges from 0.98 to 3.05 kBq/m 3 with an average of 2.29 kBq/m 3 . Indoors radon concentration measurements versus floor elevation showed that the maximum concentration was in the basement and decreases gradually for upper floors. A considerable variation in concentration levels for the same floor in the different sectors was noticed and attributed to the difference in the type of the soil of each sector. Results showed that soil and indoors radon concentration are strongly related for the same area of study. In general, it is found that the average indoor radon concentration in Jerash city is 49.21 Bq/m 3 . The measured radon levels are within the globally accepted values and no unusual concentrations were observed.

A simulation of the interaction of neutrons emitted from a 252Cf source with a CR-39 detector is presented in this paper. Elastic and inelastic neutron interactions occur with the constituent materials of the CR-39 detector. Inelastic scatterings only consider (n, a) and (n, p) reactions. Fast neutrons tracks are, mainly, produced by recoil particle tracks in the plastic nuclear track detector as a result of the elastic scattering reaction of neutrons with the constituent materials of the solid-state nuclear track detectors, especially hydrogen nuclei. The energy of the neutron, incident position, direction, and type of interaction were sampled by the Monte Carlo method. The energy threshold, critical angle and scattering angle to the detector surface normal were the most important factors considered in our calculations. The energy deposited per neutron mass unit was calculated. The angular response was determined by both Monte Carlo simulation and experimental results. The number of visible proton tracks and energy deposited per neutron per visible track were calculated and simulated. The threshold energy of the recoil proton as a function of the thickness and incident proton angles was measured by the etchable range of protons at scattering angles, along with the shape and diameter of the track. Experimental and simulations result were in good agreement.

Seismic activities around the world requires one to investigate and develop new methods for the prediction of earthquakes. The seismic studies provide evidence which indicate that significant variations of radon concentration may occur in association with major geophysical events. In these studies, some predictions have been done using many methods and techniques. One of these methods is to observe variations of radon gas concentration in soil and groundwaters. The Aegean region has allway suffers from several tectonic activities. Izmir and its surrounding located in this region have been frequently effected by earthquakes through historical and antique periods. In this study, possible relationships has been investigated between seismic data and the radiation of radon concentration as a precursor for earthquakes in Doganbey fault zone that has high risk level for Izmir. In this fault zone, radon concentrations in waters and soils have been measured using collector method and nuclear track detectors, respectively. Data given by Bogazici University Kandilli Observatory and Earthquake research Institute was considered in order to correlate with experimental results. The annual radon concentrations measured using collector method in four stations of thermal waters during one year varied from 0.28 Bq L -1 to 11.01 Bq L -1 . The radon concentrations found using nuclear track detectors (LR115) in soils of thermal water fields varied from 50 track cm -2 week -1 to 750 track cm -2 week -1 . Comparing the radon data obtained using both methods with earthquake magnitudes, it could be said that there is a positive correlation between radon emanation rate and seismic activities in the area under investigation.

The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described.

In this research, a passive diffusion chamber has been developed for separated measurement of radon and thoron. The chamber consists of two volumes which are separated by a fiber glass filter. Two lexan polycarbonate nuclear track detectors (film) are placed inside of the volumes to detect the alpha particles of radon/thorn and/or their progenies. Another lexan polycarbonate detector covered with an optimized thickness of an attenuator is placed outside of the chamber to measure only 212Po which its concentration can be related to that of long-life thoron progeny, 212Pb. The sensitivities have been measured by 2.06 and 0.053 [tracks cm−2(kBq m−3 day)−1] values for radon and thoron respectively inside of the chamber, and 7960 [tracks cm−2(kBq m−3 day)−1] value for thoron outside of the chamber. So the system can be successfully used for separated measurement of an extended range of radon/thoron concentrations in dwellings.

A role of the unstable nuclei ${}^{6}$Be, ${}^{8}$Be and ${}^{9}$B in the dissociation of relativistic nuclei ${}^{7,9}$Be, ${}^{10}$B and ${}^{10,11}$C is under study on the basis of nuclear track emulsion exposed to secondary beams of the JINR Nuclotron. Contribution of the configuration ${}^{6}$Be + $\mit{n}$ to the ${}^{7}$Be nucleus structure is 8 $\pm$ 1% which is near the value for the configuration ${}^{6}$Li + $\mit{p}$. Distributions over the opening angle of $\alpha$-particle pairs indicate to a simultaneous presence of virtual ${}^{8}$Be$_{g.s.}$ and ${}^{8}$Be$_{2^+}$ states in the ground states of the ${}^{9}$Be and ${}^{10}$C nuclei. The core ${}^{9}$B is manifested in the {${}^{10}$C} nucleus with a probability of 30 $\pm$ 4%. Selection of the ${}^{10}$C "white" stars accompanied by ${}^{8}$Be$_{g.s.}$ (${}^{9}$B) leads to appearance in the excitation energy distribution of 2$\alpha$2$\mit{p}$ "quartets" of the distinct peak with a maximum at 4.1 $\pm$ 0.3 MeV. ${}^{8}$Be$_{g.s.}$ decays are presented in 24 $\pm$ 7% of 2He + 2H events of the ${}^{11}$C coherent dissociation and 27 $\pm$ 11% of the 3He ones. The channel ${}^{9}$B + H amounts 14 $\pm$ 3%. The ${}^{8}$Be$_{g.s.}$ nucleus is manifested in the coherent dissociation ${}^{10}$B $\to$ 2He + H with a probability of 25 $\pm$ 5% including 14 $\pm$ 3% of ${}^{9}$B decays. A probability ratio of the mirror channels ${}^{9}$B + $\mit{n}$ and ${}^{9}$Be + $\mit{p}$ is estimated to be 6 $\pm$ 1., Comment: To be published in Physics of Particles in Nuclei (in press)

The background indoor gamma radiation in the residential places was estimated using CaSO4:Dy-based thermoluminescent dosimeters. The indoor gamma dose varied from 71 to 327 nGy h−1 with a mean value of 162 ± 31 nGy h−1. The highest gamma dose was observed in summer and the lowest in winter. The indoor gamma radiation was also found to vary with the type of house and building materials used. Indoor radon, thoron and progeny levels were measured for different types of dwellings during four seasons of a year using LR 115 type II film-based solid state nuclear track detectors loaded in twin chamber plastic cups. The average highest radon, thoron and progeny were observed during winter, and the corresponding lowest values were observed during summer. The concentrations of radon, thoron and progenies were found to vary with the type of houses and building materials used. The highest values were observed in mud houses, and the lowest values were recorded in wooden houses. This observed variation may be attributed to changes in ventilation conditions and exhalation rate of 222Rn and 220Rn from the floor and walls of the houses. The effective dose received by the general public due to indoor gamma radiation was found to be 0.79 mSv y−1 and the corresponding values due to radon, thoron were 1.02, and 0.54 mSv y−1, respectively. The inhalation dose received by the general public of the study area was found to be lesser than the action limit of International Commission on Radiological Protection (ICRP), 2009.

In this study, samples of perlite, pumice and Ahlat stones (Ignimbrite) extracted from mines in Bitlis and samples of other building materials produced in facilities in Bitlis were collected and analyzed. Activity concentrations of (226)Ra, (232)Th and (40)K in samples of building materials were measured using NaI detector (NaI(Tl)) with an efficiency of 24%. The radon measurements of building material samples were determined using CR-39 nuclear track detectors. (226)Ra, (232)Th and (40)K radioactivity concentrations ranged from (29.6±5.9 to 228.2±38.1Bq/kg), (10.8±5.4 to 95.5±26.1Bq/kg) and (249.3±124.7 to 2580.1±266.9Bq/kg), respectively. Radon concentration, radium equivalent activities, absorbed dose rate, excess lifetime cancer risk and the values of hazard indices were calculated for the measured samples to assess the radiation hazards arising from using those materials in the construction of dwellings. Radon concentration ranged between 89.2±12.0Bq/m(3) and 1141.0±225.0Bq/m(3). It was determined that Raeq values of samples conformed to world standards except for perlite and single samples of brick and Ahlat stone. Calculated values of absorbed dose rate ranged from 81.3±20.5 to 420.6±42.8nGy/h. ELCR values ranged from (1.8±0.3)×10(-3) to (9.0±1.0)×10(-3). All samples had ELCR values higher than the world average. The values of Hin and Hex varied from 0.35±0.11 to 1.78±0.18 and from 0.37±0.09 to 1.17±0.13, respectively. The results were compared with standard radioactivity values determined by international organizations and with similar studies. There would be a radiation risk for people living in buildings made of perlite, Ahlat-1 and Brick-3.

Progress in the study of nuclear clustering in the relativistic 10 C and 11 C nuclei dissociation in nuclear track emulsion is presented. The contribution of the unbound 8 Be and 9 B nuclei to their structure is determined on the basis of measurements of the emission angles of relativistic He and H fragments.

In this note, we point out a serious fallacy in a formula that has appeared in literature for calculating the Rn-222 exhalation rates using the Solid-State Nuclear Track Detector (SSNTD) based sealed can technique. It is shown that this formula underestimates true exhalation rates by a factor of more than 10(6). Several publications have used this formula instead of the well-known Abu-Jarad formula and have reported unrealistically low (mu Bq/m(2)/d) surface exhalation rates for normal materials. (C) 2016 Elsevier Ltd. All rights reserved.

Subject of this study is an investigation of the variations of indoor radon concentration and ambient dose equivalent rate in outdoor and indoor environments of 40 dwellings, 31 elementary schools and five kindergartens. The buildings are located in three municipalities of two, geologically different, areas of the Republic of Macedonia. Indoor radon concentrations were measured by nuclear track detectors, deployed in the most occupied room of the building, between June 2013 and May 2014. During the deploying campaign, indoor and outdoor ambient dose equivalent rates were measured simultaneously at the same location. It appeared that the measured values varied from 22 to 990 Bq/m(3) for indoor radon concentrations, from 50 to 195 nSv/h for outdoor ambient dose equivalent rates, and from 38 to 184 nSv/h for indoor ambient dose equivalent rates. The geometric mean value of indoor to outdoor ambient dose equivalent rates was found to be 0.88, i.e. the outdoor ambient dose equivalent rates were on average higher than the indoor ambient dose equivalent rates. All measured can reasonably well be described by log-normal distributions. A detailed statistical analysis of factors which influence the measured quantities is reported.

Radon is an odorless, tasteless, colorless noble radioactive gas which is produced within the radioactive decay chain of Uranium. The Radon forms in rocks, diffuses into soil and then escapes into atmosphere. When human exposure to high concentration of radon gas from inside, risk of developing lung cancer is increased. There are many methods to determine 222Rn concentration in the air. In this study, radon concentration of confined air spaces were measured by using LR-115 solid state nuclear track detectors. 509 LR-115 nuclear trace detectors were placed to 25 schools in Fatih District and they effective dose values were calculated. The results of measurements showed that the radon concentration varies between 40-395 Bq/m3. This results compared with Turkey’s limits (400 Bq/m3) are low, conversely higher compared with WHO’s limits (100 Bq/m3).

Elemental analysis of textile dyes may provide valuable information concerning the content and concentrations of element, especially the toxic ones. Such information monitors the safety of handling and using these dyes in textile industry. In addition to the safety of wearing of clothes stained with these dyes. In the present work, the specific activity of both radon and thoron were measured in nine textile dyes by using alpha emitters registration which are emitted from radon and thoron gases in CR-39 nuclear track detectors. Unexpectedly, the results obtained reports a high concentration of both radon and thoron gases in some samples (samples D5 and D9). Also the concentration of toxic elements (Cu, Pb, Zn, Mn, Cd and Cr) in textile dyes were determined by flame and graphite furnace atomic absorption spectrometry.

In the present study, CR39 track etch detector was calibrated with a new system and the total charge changing cross-section of 300 A MeV Fe 26+ ion beam in aluminum target was measured. The CR39 nuclear track detectors were used to identify the incident charged particles and their fragments using an optical microscope DM6000 M and automated image analyzer system installed with Leica QWin Plus software. The CR39 detectors before and after the target were calibrated and found to have the same charge response; the charge resolution in both of the detectors were 0.19e and 0.20e, respectively. The calibration points were fitted with a polynomial of degree one and all the points are within the limits of the experimental errors. The response functions were also obtained and fitted with a polynomial of degree three which are quite good throughout Z / β = 4.6 to 41.4. The value of the total charge changing cross-section is σ tot = (1663 ± 236) mb. The total charge changing cross-section was compared with the experimental results of others and also fitted by the Bradt-Peters geometrical cross-section.

The total charge-changing cross sections and the partial cross sections for the production of projectile fragment are measured in the interactions of 388 A MeV 20Ne with aluminum, carbon and polyethylene targets sandwiched with CR-39 plastic nuclear track detectors. The measured total charge-changing cross sections are compared with the prediction using Bradt–Peters semi-empirical formula, and NUCFRG2 and PHITS models. It is shown that the measured experimental results are in good agreement with theoretical model predictions. The partial cross sections for projectile fragment production are consistent with other experimental results at same and nearly the same energies except for fragment with charge Z = 5. The partial cross sections of fragment with charge Z = 5 from C and Al targets are smaller than other experimental results, and the result from H target is greater than that of other experiments, which can be explained by the limitation of detection efficiency of CR-39. Finally, it is clearly seen that the partial cross sections for projectile fragment production show obvious odd–even effects.

Radon measurements, as do any measurements, include errors in their readings. The relative values of such errors depend principally on the measurement methods used, the radon concentration to be measured and the duration of the measurements. Typical exposure times for radon surveys using passive detectors [nuclear track detectors, activated charcoal, electrostatic (E-perm), etc.)] may extend from a few days to months, whereas, in the case of screening methods utilising active radon monitors (AlphaGUARD, RAD7, EQF, etc.), the measurements may be completed quickly within a few hours to a few days. Thus, the latter may have relatively large error values, which affect the measurement accuracy significantly compared with the former measurements made over long time periods. The method presented in this paper examines the uncertainty of a short-term radon measurement as an estimate of the long-term mean and suggests a minimum measurement time to achieve a given margin of uncertainty of that estimate.

Enclosed spaces in contact with soil, the main source of radon, like greenhouses have potentially high radon (222Rn) concentrations. Greenhouses are frequented by visitors and also are workplaces. The study of radon concentrations in greenhouses is, thus, a relevant concern for public health and environmental radiation authorities. For this study, the radon concentrations in 12 greenhouses in different locations within Mexico City were measured using nuclear track methodology. The detectors used for the study consisted of the well-known closed-end cup device, with CR-39 Lantrack® as detector material. The measurements were carried out over a period of one year, divided into four three-month sub-periods. The lowest and highest annual mean radon concentrations found in individual greenhouses were 17.0 and 45.1 Bq/m3, respectively. The annual mean averaged over all 12 greenhouses was 27.3 Bq/m3. No significant seasonal variation was observed. Using the highest annual mean radon concentration found in an individual greenhouse, and an equilibrium factor of 0.4, the effective dose from 222Rn and its progenies was calculated to be 339.9 nSv/h. This corresponds to an annual dose rate of 679.8 μSv/y (0.057 WLM/y) for a worker spending 4 h a day, 5 days a week, 50 weeks a year, inside the greenhouse. For a visitor spending 12 h a year inside the greenhouse the annual dose is 2.469 μSv/y. The study of indoor radon concentrations in closed buildings such as greenhouses, which are both workplaces and open to visitors, is an important public health consideration.

This work presents the results of a study of the radon levels in four caves in Mexico: Los Riscos Cave and El Judio Cave in the State of Queretaro, and Coyozochico Cave and Karmidas Cave in the State of Puebla. The measurements were made using the passive closed-end cup system, with CR-39 (Lantrack®) as detection material, and following protocols established for the measurement of indoor radon, developed at the Dosimetry Applications Project of the Physics Institute of the Universidad Nacional Autonoma de Mexico. The radon concentration at one location with Karmidas Cave reached more than 60,000 Bq/m3, while concentrations in the other three caves varied from 83.1–1216.0 Bq/m3, was found. During the study was observed an interesting coincidence between the radon concentration distribution inside the caves, and the bat colonies location. In general, the bat colonies are located at the medium or low radon concentration levels zones.

More than half of the radiation dose of natural origin comes from radon. However, according to some surveys in certain cases, the radiation dose originating from thoron may be considerable. Among the factors disturbing the measurement of radon, the presence of thoron may also influence the measured radon value, making the estimated radiation exposure imprecise. Thoron has previously been surveyed, mainly in Asia; however, recent surveys for some European locations have found that significant thoron concentrations also need to be considered. In this survey, several types of commercially available SSNTDs (solid-state nuclear track detectors) capable of measuring both radon and thoron were placed at the same time in 73 houses and 7 workplaces in Hungary with 3-month exposition periods. In order to measure thoron, the distance of the detector sets was fixed as 15-20 cm from the walls. The radon concentration was measured with five types of SSNTDs: NRPB, NRPB SSI, Raduet, DTPS and DRPS. The first four types had relatively good accordance (within ± 10 %), but the results of the DRPS detectors were considerably lower when compared with other detectors for radon concentrations over 100 Bq m(-3). The thoron averages were provided by two different types of detectors: Raduet and DTPS. The difference between their average results was more than 30 % and was six times the maximum values. Therefore, the thoron measurement results were judged to be erroneous, and their measurement protocol should be clearly established for future work.

Uranium and thorium concentrations in some soil and fertilizer samples were determined using passive technique with CR-39 and LR-115 polymeric nuclear track detectors, whereas the fertilizer samples were measured using active technique with passive technique. The two different techniques have been used in order to ensure and compare between the obtained results. The main purpose of the present investigation is to assess the activity concentration of 238 U and 232 Th in soil of particular regions and measure the pollution due to the production plant of complex fertilizers. From the obtained data we can conclude that there is no radioactive healthy hazard for human and living beings in the selected area.

Indoor radon concentrations were measured in four well-known spas of Tunisia using nuclear track detectors. The radon concentrations in these spas were found to be in the range of 19 - 870 Bq.m-3 . The equilibrium factor F between radon and its progeny was found to vary in the range of 0.2 - 0.5, depending upon the ventilation rates within the buildings of the spas. Using the exposure-dose conversion factor, the effective doses to patients and workers were estimated and the dose was found to vary in the range 3.7 × 10-3 - 12.5 × 10-3 mSv.y-1 and 0.45 - 1.5 mSv.y-1 for patients and workers, respectively. These values are well inside the limit recommended for the annual dose limit of 20 mSv.y-1 for an occupational worker. The radium content in the groundwater of all four spas was measured and the results showed no correlation between the 226 Ra concentration in water and radon concentration in indoor air of the investigated spas.

The subsoil radon gas anomaly in and around the anticlinal structure of the Geleki oilfield, Assam Shelf was studied using LR-115 (II) nuclear track detectors following a grid-sampling pattern. The present study was undertaken to understand the variability of the soil-gas radon concentrations with reference to the oil-wells, drilling activities and local geology. From the alpha-tracks formed on the detectors, the soil-gas radon concentrations were determined using a Spark Counter. The results showed that the natural background soil-gas radon radiation levels in the Geleki oilfield ranged from 1 to 5 kBq/m3 over the subsurface reservoir with anomaly of enhanced values of 12–13 kBq/m3 around the periphery of the oilfield. It has been concluded from the observed soil-gas radon distribution patterns that drilling beyond the extent of the northwestern and eastern corners of the oilfield may yield potential subsurface oil accumulations.

The Gas of the radon (Rn-222) can reach into the space of the houses in many ways, such as water supply, the emission from building materials, and the leakage through the soil. The aim of this study is determination of the concentrations of radon and uranium in ten soil samples of the sediment mud of houses' water tanks in Nineveh province, as well as ten soil samples have been taken from the same areas. This was achieved by using a technique of accounting the accumulative nuclear track on the detector LR-115, and by using the test tubes. The results indicated that the concentrations of the radon and uranium in the sediment mud were (4.98-40.555kBq.m3) & (0.35-2.83ppm) respectively, were as the values of soil samples were (1,44-58.84 kBq.m3) & (0.08-3.3ppm) respectively.

Atmospheric radon concentration was continuously monitored in Bucharest-Magurele area both near the ground at 1 m height as well as at 10 m height. This paper presents the results of radon in air near the ground concentrations obtained during the 1 July 2010 to 1 February 2012 period by use of solid state nuclear track detectors SSNTD CR-39. The mean atmospheric radon concentration near the ground at 1 m height was found to be 360.91 ± 66.49 Bq/m3, which was about more than an order of magnitude lower than average radon concentration in range of 44.92 ± 9.94 Bq/m3 recorded for period 1 August 2011 to 20 December 2011 at 10 m height by AlphaGUARD Radon monitor. The meteorological effects on the variation of atmospheric radon concentration were discussed. The analysis of spatio-temporal variations in time series radon concentration in air near the ground is a useful tool to study geo-dynamical processes associated with seismic activity in active Vrancea zone in Romania. Taking off the variations induced by external variables, such as temperature, barometric pressure, rainfall, and other meteorological parameters, can be assessed radon anomalies due to possible tectonic movements and also can be surveyed radioactivity background in relation with nuclear emergencies.