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The Regener-Pfotzer (RP) maximum is the altitude at which cosmic radiation intensity is the greatest. A decrease of the altitude of the interaction layer, assumed to be measured by the RP maximum, has been suggested to account for a reduction in the secondary cosmic ray flux measured at the surface of the Earth during a total solar eclipse. To investigate this suggestion, high altitude cosmic radiation was measured using Geiger Mueller (GM) counters carried beneath weather balloons both before and during the total solar eclipse on 21 August 2017. The 19 and 20 August 2017 omnidirectional RP maxima occurred at an average altitude of 20.2 km ± 0.9 km. During the eclipse of 21 August 2017 the omnidirectional RP maxima occurred at an altitude of 20.4 km ± 0.8 km. The 19 and 20 August 2017 vertical coincidence RP maxima occurred at an altitude of 18.3 km ± 1.0 km. During the eclipse the vertical coincidence RP maxima occurred at 18.0 km ± 1.0 km. Our results do not show any decrease in the altitude of either the omnidirectional or the vertical coincidence RP maximum outside the range of our measurements before the eclipse.

This study introduces the climates of Iran defined by Köppen-Geiger, Feddema’s, and UNPEP classifications that applied to a high-resolution ground-based gridded data set relative to the 1985–2017 period. Ten Köppen-Geiger climate types were found for Iran, from which Bwh, Bsk, Csa, Bsh, and Bwk cumulatively account for more than 98% of the territory. Likewise, from 36 possible Feddema’s climate types, Iran possesses fifteen climate types from which the Dry Cool, Semiarid Torrid, Semiarid Hot, Semiarid Warm, Dry warm, Semiarid Cool, and Moist Cool climates collectively occupied approximately 93% of the country. Similarly, arid, semi-arid, humid, and sub-humid UNEP climate types characterized more than 98% of Iran. A few other vertically stratified climates appeared at the highlands of Iran just because of changes in elevation and slope aspects of the mountains. The combined effect of topography and vicinity to sea also creates very distinct climate types in northern Iran. The climate maps of the three used methods reflect the joint effects of topography, latitudinal variation, and land/sea surface contrast on the climate of Iran. A pairwise comparison made between the three classifications showed a satisfactory agreement between the three schemes in representing the main climate types of Iran.

Ionizing radiations have hazardous health effects upon human beings. Different types of cancers and genetic mutations may arise from the overexposure to ionizing radiations like alpha-particles, beta-particles, gamma-rays, x-rays etc. For this reason, it is necessary to measure the background radiation of each place and that can be done by a Geiger Muller (GM) counter. This paper describes the development of a Geiger Mueller counter with ESP32 microcontroller and also a user-friendly dashboard with Node-RED. A microcontroller electronic circuit for the monitoring radiation system with an operation algorithm with micropython programming language is developed.

En la protección radiológica es importante medir la dosis de entrada en piel como indicador dosimétrico directo o como dato base para un cálculo posterior de la dosis efectiva o equivalente. Los Contadores Geiger son detectores de partículas y de radiación ionizante que emiten las diferentes fuentes de radiación, se emplean como dosímetros ambientales, midiendo la tasa de dosis equivalente en aire en puntos claves de las áreas expuestas y no expuestas en los servicios de radiología. El presente artículo muestra la construcción de un contador Geiger Müller a partir del aprovechamiento de tecnologías de código abierto como el Arduino, dichos sistemas permiten la integración de diferentes aplicaciones a costos muy asequibles, fácil programación y ensamble, el dispositivo no solo permite la medición de las dosis de radiación percibida en el áreas de radiología convencional, sino que además posee un termohigrómetro captando dos variables extra fundamentales para monitoreo de temperatura y la humedad relativa del entorno donde se esté operando el equipo, en su configuración el prototipo realiza mediciones de manera remota y en tiempo real, sin exponer al profesional que realice el monitoreo; con la ubicación del dispositivo en el sitio adecuado se transmite dicha medida para ser visualizada desde cualquier dispositivo de computo o móvil, además a través del envío a plataformas de visualización, teniendo la libertad de realizar seguimiento continuo, almacenando dicha información para llevar un control estricto en el manejo de las emisiones en las salas donde los diferentes equipos radiológicos operen.

Based on the theoretical simulation of Geiger-Miieller (GM) tube in the model of GJ4105 with Monte Carlo software Geant4, the response of GM counter tube to the wide energy range of y rays and the detection efficiency curve are analyzed. Some factors that influence energy response are analyzed, which provides the basis for the optimal design of structure and performance of GM tube.

Measurement of gamma radiation dose rates based on soil types and geological formations was carried out as a pioneer study in Jordan extensively. 823 measurements were taken at 1 m above the ground using two survey meters (Inspector Alert manufactured by S.E. International and Radiagem, 2000 Geiger Muller Counter) and the coordinates of each measurement point was recorded using a geographical positioning system (GPS). The measured GDR was found to range from 35 nGy h−1 to 470 nGy h−1 with a mean value of 90 nGy h−1 which is one and half times higher than the world's average value of 59 nGy h−1. Unbalanced one-way ANOVA test was used to investigate the variations of GDRs among all geological formations and soil types. The results indicated that there exists a strong significant difference as a result of varying soil types and geological formations. The highest mean value of 137 nGy h−1 was recorded for Acid intrusive granite rocks of Precambrian geological formation, while the lowest mean value of 65 nGy h−1 was found against Jurassic geological formation, composed of soil originated from clay and unconsolidated sedimentary rock. The results were used in production of digital map (using ArcGIS 10.2) for isodose to characterize exposure rates caused by GDR of the study area. This study will also help in establishing a GDR baseline data for future references in Jordan.

On a cold, snowy January night in Juneau, Alaska, Will Geiger and I convened at Ishmael Hope’s home—with his wife, Lily, and their five children—for dinner and cordiality in advance of our recording session. The Hope family is exceedingly generous with their time and knowledge, and, as is the case whenever we gather at the Hope home, one can palpably discern the multigenerational inspirations and relations that sustain their work, artistry, and community involvement. Once the children went to bed, we dimmed the lights and pulled out our books.When the editors of Screen Bodies told me that the journal was interested in expanding notions of screen beyond cinema, I inquired about the possibility of interviewing Ishmael Hope and others on Tlingit house screens and, by a kind of phenomenological appeal, of focusing the conversation through a concern for embodiment. Originally, Ishmael and I invited Will Geiger and Forest Haven, a brilliant Tsimshian PhD candidate from University of California, Irvine, to participate, but Forest was unfortunately unable to attend. Over the years, I have worked closely with these three on a number of academic projects, developing a tight and trusted friendship sustained by mutual respect and interwoven eruditions.

A hand-made air GM counter was developed using simple, low-cost and easily available materials. The detector was successful in demonstrating the inverse square law, shielding effect, and determining the half-life of thoron gas. The possibility of using the tube design as a simple proportional counter to provide energy information has been explored and preliminary experiment and simulation results appear to agree at low energy. The energy deposition characteristics for an internally placed alpha-emitting Rn-220 were simulated using Particle and Heavy Ion Transport code System (PHITS).

4H-SiC avalanche photodiodes (APDs) working in Geiger mode are promising devices for ultra-weak ultraviolet light detection. In this letter, the degree of avalanche uniformity across device mesa of 4H-SiC p-i-n APDs is studied by imaging hot carrier luminescence pattern of the devices in avalanche regime. It is found that the luminescence emission from the APD under avalanche always first appears in the [ $\overline 1 \overline 1 20$ ] side of the top contact electrode. As over-bias increases, the luminescence pattern gradually extends toward the [ $11\overline 2 0$ ] direction and finally covers the whole device mesa. A physical model is proposed to explain the non-uniform avalanche phenomenon, in which the substrate off-orientation related carrier lateral drift would cause asymmetric hole accumulation and screening of junction electrical field along the [ $11\overline 2 0$ ] direction.

The microscopic slit bearing gastropods of the northeastern Pacific are reviewed. Since the global monograph of Geiger (2012), one additional species has been described (Anatoma georgii Geiger, 2017). No significant material of other species has changed distributional records or range limits of the known taxa.

Present study area, which is located in the Central Range Fault (CRF) in the island of Trinidad, can provide solution to that problem as this strike-slip fault system is reported to be active in present time (during Holocene, most current geological epoch) with a movement of geodetic rate of 12 ± 3 mm/yr. Most recent work, with improved GPS time series analysis indicated that as creeping fault rather than locked fault. Moreover, the selected fault system is accompanied by mud volcanoes, which can amplify the level of radiation activity by slight but significant anomalies as described by some researchers from other areas. Furthermore, being one of the first environmental radiation study in the Caribbean Islands, this study is significant. With the aim to achieve a continuous monitoring of radiological data to assess the activity along CRF for possible earthquake forecasting, objectives of this preliminary investigation are to delineate CRFZ using radiation survey and to investigate the potential of using this survey to detect tectonic activities in this zone. As a pilot study, radiation measurements were carried out with the help of a portable Geiger Muller counter in 52 locations along the 25 km long section of CRF between Naved Dam and Pointe-a-Pierre. Radiation measurements were taken both at 1 m level above the surface and at nearly 1 m below the ground. Results from this pilot study showed that lithology was not the lone contributor to terrestrial radiation levels, as CRFZ and associated fissure plane have good control also (∼3–5 times higher than the average background level). Although present study was not able to indicate the possibility of earthquakes in recent times (as previously stated), however, elevated radiation values in the vicinity of CRF, associated fissures (possibly interconnected fractures) and active mud volcanoes indicate possible activity in the study area. However, detail and periodic radiological studies are required before concluding that CRF is a creep fault rather than a locked fault.

The imaging flash lidar has been considered as a promising sensor for the future space missions such as autonomous safe landing, spacecraft rendezvous and docking due to its ability to provide a full 3D scene with a single or multiple laser pulses. The linear-mode flash lidar has been developed and demonstrated for an autonomous safe landing on the Moon in order to provide an accurate distance measurement to the landing site and its 3D image. Yet, the Geiger-mode flash lidar has also been recognized as an emerging technology for the space missions because it is highly sensitive even to a single photon and provides the very accurate timing of photon arrival. In this study, the performance of the Geiger-mode flash lidar is simulated in the approach phase and evaluated for the autonomous landing on the Moon. Furthermore, a new statistical signal processing algorithm is proposed to remove the noise counts in order to obtain the 3D image from a sequence of laser pulses in the situation of the fast moving spacecraft. The algorithm is shown to be effective for the autonomous landing due to its ability to remove noise events under the condition of low signal-to-noise ratio and improve ranging accuracy.

Theoretical analysis and two-dimensional simulation of InGaAs/InAlAs avalanche photodiodes (APDs) and single-photon APDs (SPADs) are reported. The electric-field distribution and tunneling effect of InGaAs/InAlAs APDs and SPADs are studied. When the InGaAs/InAlAs SPADs are operated under the Geiger mode, the electric field increases linearly in the absorption layer and deviate down from its linear relations in the multiplication layer. Considering the tunneling threshold electric field in multiplication layer, the thickness of the multiplication layer should be larger than 300 nm. Moreover, SPADs can work under a large bias voltage to avoid tunneling in absorption layer with high doping concentrations in the charge layer.

Silicon photo-multipliers (SiPMs) and multipixel photon counters (MPPCs) are solid-state silicon photosensors operating in the Geiger mode. These photosensors possess high gain and high timing performance. In the field of medicine, these photosensors are employed in positron emission tomography (PET), and their features are used for time-of-flight PET (TOF-PET). We designed a 48 channels front-end application specific integration circuit (ASIC) for MPPCs of the TOF-PET system. The circuit in the ASIC consists of a current processing method for realizing a high speed performance. At the output stage, a current mode Time-over-Threshold (ToT) circuit was implemented. The current mode ToT converts the current signal from the MPPC into a digital pulse signal and supplies the timing and energy information. We performed experiments for timing resolution measurement, spectra measurement, and coincidence measurement.

Measurement of radioactive contamination in some commonly consumed foodstuffs within the six area councils of Abuja, Nigeria was conducted in this study by means of a very sensitive and portable 3M/3-X Geiger Müller counter-based environmental radiation dosimeter. Eight different food samples were randomly selected in each of the sample locations making a total of 48 foodstuffs samples surveyed across the six area councils. The results obtained show that, the range of radiation dose levels in the analyzed samples varied from 0.01590.0001 to 0.34070.0002 μSvy-1 at Bwari; 0.14900.0001 to 0.39020.0002 μSvy-1 at AMAC; 0.00950.0001 to 0.02090.0001 μSvy-1 at Gwagwalada; 0.00570.0001 to 0.01330.0002 μSvy-1 at Kuje; 0.02740.0001 to 0.22710.0002 μSvy-1 at Abaji; Kwali was between 0.01820.0001 and 0.35030.0002 μSvy-1, and their corresponding arithmetic mean are 0.16900.0001 μSvy-1, 0.22560.0001 μSvy-1, 0.01330.0001 μSvy-1, 0.00880.0001 μSvy-1, 0.13600.0001 μSvy-1 and 0.12370.0001 μSvy-1, which gives estimated annual effective dose rates of 0.18850.0003 mSvy-1, 0.25760.0001 mSvy-1, 0.11700.0001 mSvy-1, 0.07710.0001 mSvy-1, 0.15530.0002 mSvy-1, and 0.14120.0001 mSvy-1 for Bwari, AMAC, Gwagwalada, Kuje, Abaji and Kwali area councils respectively. This finding reveals that the obtained values were sufficiently less than the maximum recommended global average exposure dose limit for environmental background (2.4 mSvy-1) and general public dose limit (1.0 mSvy-1). The radiation dose levels and dose rates associated with the intake of foodstuffs across the area councils are, therefore, relatively low and may not pose any immediate radiological health hazard to the populace, as deterministic radiation effects occur only in extreme cases.

Progress in radioanalytical science, mainly in radiometrics and mass spectrometry technologies for ultra-sensitive analyses of radionuclides applied in natural sciences is shortly reviewed. While in the radiometrics sector the greatest developments have been made in underground Ge gamma-spectrometry, in the mass spectrometry sector the accelerator mass spectrometry had dominant position reaching the status of single atom counting and compound specific analysis for some long-lived radionuclides.

Analysis of several pulse shape properties generated by a Geiger Mueller (GM) detector and its dependence on applied voltage was performed. The two-source method was utilized to measure deadtime while simultaneously capturing pulse shape parameters on an oscilloscope. A wide range of operating voltages (600–1200 V) beyond the recommended operating voltage of 900 V was investigated using three radioactive sources (204Tl, 137Cs, 22Na). This study investigates the relationship between operating voltage, pulse shape properties, and deadtime of the detector. Based on the data, it is found that deadtime decreases with increasing voltage from 600 to 650 V. At these low voltages (600–650 V), the collection time was long, allowing sufficient time for some recombination to take place. Increasing the voltage in this range decreased the collection time, and hence deadtime decreased. It is also observed that rise and fall time were at their highest at these applied voltages. Increasing the voltage further would result in gas multiplication, where deadtime and pulse width are observed to be increasing. After reaching the maximum point of deadtime (~ 250 µs at ~ 700 V), deadtime started to exponentially decrease until a plateau was reached. In this region, it is observed that detector deadtime and operating voltage show a strong correlation with positive pulse width, rise and fall time, cycle mean, and area. Therefore, this study confirms a correlation between detector deadtime, operating voltage, and pulse shape properties. The results will validate our hypothesis that deadtime phenomena at different operating voltages are phenomenologically different.

This paper proposes a nuclear power plant monitoring system using drones. Existing surveillance systems have a disadvantage in that manpower is wasted due to the blind spots of fixed observatories and CCTVs, and it is impossible to quickly respond to situations. The proposed system detects motion winners and suspicious vehicles around nuclear power plants by using object detection technology using thermal imaging cameras and autonomous flight technology and also measures radiation levels and temperature data using Geiger counters and temperature sensors. Data can be transmitted through the 5G/LTE module and monitored in real-time.

Single photon avalanche diode (SPAD) in Geiger mode is a kind of detector which can detect extremely faint signal, and has been greatly developed in recent years due to the single photon sensitivity, time resolution on the order of picoseconds and high photon-detection efficiency. The device has been widely applied in time-resolved spectrum measurement, quantum imaging and quantum cryptography. The dark count rate (DCR) is one of the key parameters to judge the performance of the device. However, high DCR is a common problem in the world, especially for the device with large sensitive area. In recent years, the research of the device with low DCR is in-depth, and some remarkable achievements have been made, including the establishment of the physical simulation model and the optimization of structure. In this paper, based on the previous research results, we analyze the physical mechanism of the generation of DCR, including Shockley Read Hall (SRH), Trap-Assisted Tunneling (TAT), and Band to Band Tunneling (BTBT), and describe the method of physical model simulation using Technology Computer-Aided Design (TCAD) software. On the other hand, we have studied the structure of the device with low DCR and summarize their advantages, respectively. It is hoped that through in-depth research on the physical model and structure design theory, we can find a way to reduce the DCR of the device, so as to improve its performance.

At first glance, Moritz Geiger’s reaction to Husserl’s Ideas I appears to be neither systematically articulated nor particularly original. Geiger talks about Husserl’s idealism in Ideas I in just a few passages from his book Die Wirklickheit der Wissenschaften und die Metaphysik (1930), and in a short essay in praise of Alexander Pfander, Alexander Pfanders Methodische Stellung (1933). There, Geiger seems to follow a general line of criticism shared by several so-called early phenomenologists, and most fully articulated by Jean Hering, Roman Ingarden, Theodor Celms and Max Scheler. In this paper I argue that Geiger’s reaction to Ideas I contains some well-developed and original contributions to phenomenological thought. In particular, I defend three theses. First, Geiger’s criticism of Husserl’s idealism is much more original and sophisticated than it at first appears, because it rests on a complex phenomenology of “attitudes” [Einstellungen]. Second, Geiger offers a unique account of phenomenology as a variation of “stance” [Haltung], rather than a variation of attitude. Third, Geiger points to an alternative kind of phenomenology, which I call certainty-based phenomenology as opposed to an evidence-based phenomenology. Elements of this certainty-based phenomenology can be found in thinkers such as Merleau-Ponty and Ricoeur, but many of their views are significantly anticipated by Geiger.