The Geiger counter and the chair

An awkward question from an amateur science buff makes the author realise they do not fully understand what defines a quantum measuring device.

Isotope Exchange Kinetics in Clay-Water System

<p>Knowledge of reactions at solid/liquid and solid/gas interfaces is of great importance in the study of all adsorption phenomena. Techniques that enable a study of molecules (liquid or gaseous) adsorbed onto a surface may be divided into two categories: (a) those that upset the equilibrium between molecules in the gaseous (or liquid) phase above the solid surface and molecules actually adsorbed onto it, and (b) those that do not. Those techniques that do not disturb this equilibrium will give results that would be expected to have greater reliability than those obtained from techniques that upset this equilibrium (for example by heating or by affecting one component of the equilibrium by titration, precipitation etc.) In an endeavour to study the properties of water adsorbed onto various substances such as clay, wool and textile fibres without affecting the equilibrium the technique of isotopic exchange has been developed. Essentially the procedure is to take a closed adsorber system in equilibrium with a gas (or liquid), part of which is in the sensitive region of a geiger counter, and to add a very small amount of radioactively labelled gas (or liquid) to the system. The adsorber is placed in the bottom of a geiger counter out of the sensitive volume and a known fraction of gas (or liquid) is in the sensitive volume. As the system is at equilibrium there is continuous exchange between the adsorbed molecules on the sample and the molecules in the gaseous (or liquid) state. Thus, when a very small amount, by weight, of the radioactively labelled gas (or liquid) is added to the system, exchange will take place with the non-radioactive molecules adsorbed on the surface of the material under study. Thus radioactivity will be removed from the sensitive volume of the geiger counter and adsorbed onto the surface of the material, and so the specific activity (count rate), as measured with the geiger counter, will drop. The advantage of this technique is that the equilibrium between the adsorbed molecules and the free gas (or liquid) is not disturbed. The actual amount of radioactive material added is so minute that there is no effective change in the concentration of the free gas (or liquid).</p>

Isotope Exchange Kinetics in Clay-Water System

<p>Knowledge of reactions at solid/liquid and solid/gas interfaces is of great importance in the study of all adsorption phenomena. Techniques that enable a study of molecules (liquid or gaseous) adsorbed onto a surface may be divided into two categories: (a) those that upset the equilibrium between molecules in the gaseous (or liquid) phase above the solid surface and molecules actually adsorbed onto it, and (b) those that do not. Those techniques that do not disturb this equilibrium will give results that would be expected to have greater reliability than those obtained from techniques that upset this equilibrium (for example by heating or by affecting one component of the equilibrium by titration, precipitation etc.) In an endeavour to study the properties of water adsorbed onto various substances such as clay, wool and textile fibres without affecting the equilibrium the technique of isotopic exchange has been developed. Essentially the procedure is to take a closed adsorber system in equilibrium with a gas (or liquid), part of which is in the sensitive region of a geiger counter, and to add a very small amount of radioactively labelled gas (or liquid) to the system. The adsorber is placed in the bottom of a geiger counter out of the sensitive volume and a known fraction of gas (or liquid) is in the sensitive volume. As the system is at equilibrium there is continuous exchange between the adsorbed molecules on the sample and the molecules in the gaseous (or liquid) state. Thus, when a very small amount, by weight, of the radioactively labelled gas (or liquid) is added to the system, exchange will take place with the non-radioactive molecules adsorbed on the surface of the material under study. Thus radioactivity will be removed from the sensitive volume of the geiger counter and adsorbed onto the surface of the material, and so the specific activity (count rate), as measured with the geiger counter, will drop. The advantage of this technique is that the equilibrium between the adsorbed molecules and the free gas (or liquid) is not disturbed. The actual amount of radioactive material added is so minute that there is no effective change in the concentration of the free gas (or liquid).</p>

Fukushima

In places such as Fukushima that have been contaminated after a nuclear disaster, attesting to the presence of radioactivity is a challenge for the people there, who all know that one cannot touch, nor see, nor smell it. Nevertheless, since 2011, they have had to learn how to cohabit with radionuclides by—among other means—measuring their environment and every single item that populates it. Although when talking about a nuclear disaster, one often imagines the kind of ‘crackle’ sound produced by Geiger counters, life in the Fukushima region is strangely soundless. Most of the time, Geiger counters are calibrated to visualize an amount of rays via numbers, but by choice they are set to mute mode. This silence is echoed by the peculiar sound of deserted areas. Looking back over the history of the Geiger counter and ethnographical depictions, it will try to grasp and render the texture of sites such as these that force us as human beings to confront this deficiency in our senses.

Detection of stratospheric X-rays with a novel microscintillator sensor

&lt;p&gt;A new energetic particle detector based on a 1 cm&lt;sup&gt;3&lt;/sup&gt; CsI(Tl) scintillator crystal responds to both particle count and energy. This offers increased measurement capability over the long-established Geiger counter technology for investigating the role of energetic particles in the atmosphere during meteorological radiosonde flights. Here we present results from three flights over the UK in 2017-18 where the detector was flown alongside Geiger counters to test its capability for measuring ionising radiation in the atmosphere. Operation of the microscintillator detector was verified by both it and the Geiger counters showing the anticipated Regener-Pfotzer maximum at around 17km. Unexpectedly however, two of the flights also detected lower energy signals at 10-100 keV. Laboratory experiments investigating the thermal response of the microscintillator, in combination with careful error analysis, can be used to show that the signals detected do not originate from instrument artefacts, and are statistically significant. These are most likely to be stratospheric X rays, usually associated with bremsstrahlung radiation generated by precipitating electrons from the radiation belts.&lt;/p&gt;

Safecast – a Citizen Science initiative for ambient dose rate mapping; Quality assurance issues.

&lt;p&gt;Safecast has been initiated in 2011 in Japan as response to the perceived inadequacy of official information policy about radioactive contamination. It is based on measurements of ambient dose rate (ADR) by numerous volunteers using a standardized monitor, called SAFECAST bGeigie Nano. In essence, it consists of a Geiger counter and a GPS module, data (ADR, GPS coordinates, date/time) are recorded on an SD card if operated in its survey mode.&lt;/p&gt;&lt;p&gt;The project quickly expanded world-wide and by end 2020, over 150 million measurements were recorded, however by far not uniformly distributed over the world (https://map.safecast.org/ ). Evidently, such amount of data cannot be reasonably acquired by institutional surveying. On the other hand, professionals can be expected to follow metrological quality assurance (QA) standards, which is usually not the case for members of the public who are mostly laypeople in metrology.&lt;/p&gt;&lt;p&gt;Thus, impressive as the Safecast map is, it raises questions related to QA. This is relevant for interpretation of the ADR values shown on the map, and their uncertainty and resulting reliability. We propose to distinguish between two aspects of metrological QA regarding monitoring in the context of citizen science.&lt;/p&gt;&lt;p&gt;(1) Metrology proper, which pertains to characterization of the measurement procedure, from sampling protocols to physical behaviour of the instrument and resulting uncertainty; this is of course equally true also for professional measuring.&lt;/p&gt;&lt;p&gt;(2) Real-world handling: not being familiar with metrological QA concepts, in general, it can be expected that citizen scientists deviate from QA standards more frequently and more severely than professionals. This adds to the uncertainty budget of reported values. Uncertainty impairs interpretability.&lt;/p&gt;&lt;p&gt;In this contribution, we report current metrological knowledge of the bGeigie Nano in the sense of aspect (1). Further, we discuss how QA in the sense of aspect (2) can be approached. We report experiments of repeated realistic handling, i.e. without caring for particularly controlled laboratory or well-defined field conditions (as in (1)) and of intentional mishandling.&lt;/p&gt;&lt;p&gt;It appears that QA type (2) is the more serious issue, both by contribution to the uncertainty budget and by difficulty in handling it. While the Safecast map provides &amp;#8211; in some regions - an astonishing dense database, one must be cautious about interpreting local data, if the measurement circumstances are not known, which is the usual case. One element of addressing the problem consists in instruction of participants about correct usage.&lt;/p&gt;&lt;p&gt;In response to certain technical issues of the bGeigie Nano which derogate its performance, S&amp;#218;RO developed an alternative but conceptually similar device called CzechRad (details in https://github.com/juhele/CzechRad) whose metrological characterization is ongoing.&lt;/p&gt;

Knowledge on radiation emergency preparedness among nuclear medicine technologists

This study aimed to assess the knowledge of nuclear medicine technologists (NMTs) in radiation emergency preparedness and response operations and their willingness to participate in such operations. A survey was developed for this purpose and distributed to NMTs in Saudi Arabia. Sixty participants responded with a response rate of 63.31%. Based on the overall radiation protection knowledge related to emergency response, NMTs can perform radiation detection, population monitoring, patient decontamination, and assist with radiological dose assessments during radiation emergencies. There were no significant differences in the knowledge on the use of scintillation gamma camera (P = 0.314), well counter (P = 0.744), Geiger counter (P = 0.935), thyroid probes (P = 0.980), portable monitor (P = 0.830), or portable multichannel analyzer (P = 0.413) and years of experience. Approximately 44% of the respondents reported receiving emergency preparedness training in the last 5 years. Respondents who reported receiving training were significantly more familiar with the emergency preparedness resources (P = 0.031) and more willing to assist with radiation detection or monitoring in the event of nuclear reactor accident (P = 0.016), nuclear weapon detonation (P = 0.002), and dirty bomb detonation (P = 0.003). These findings indicate the importance of training and continuing education in radiological emergency preparedness and response, which increase the willingness to respond to radiological accidents and fill the gaps in NMTs’ knowledge and familiarity with response resources.

How Knowledge Can Lead to the Demise of Schrodinger’s Cat Through a Negative Measurement/Null Measurement (A Quantum Mechanical Measurement in Which There is No Physical Interaction Between a Physical Measuring Apparatus and the System Measured)

The Schrodinger cat experiment (SCE) is presented. An alteration follows where the LACK of radioactive decay leads to the demise of the cat instead of the ACT of radioactive decay. The lack of radioactive decay is a negative (null) measurement (nm) (where there is NO physical interaction between the radioactive material (rm) and the Geiger counter). The negative measurement is non-trivial because all knowledge about the radioactive material (rm) is derived from its associated wave function which itself has no physical existence. The wave function is how we make probabilistic predictions regarding systems in quantum mechanics. Before the box in the SCE is opened, the wave function for the rm is: psi_rm = 1/√2 [psi_rm does not decay + psi_rm does decay] which leads to the possibility of interference before the cat is observed. As Schrodinger wrote: “The psi_function of the entire system [including radioactive material and cat] would express this by having in it the living and the dead cat (pardon the expression) mixed or smeared out in equal parts.” The wave function is the foundation for knowledge since the probabilities are derived from the wave function and the wave function contains all the information concerning a system. This alteration of the SCE underscores that the LACK of radioactive decay in the original SCE is also a negative measurement that leads to the continued life of the cat.

Thermal Analysis of Photoelectron Emission (PE) and X-ray Photoelectron Spectroscopy (XPS) Data for Iron Surfaces Scratched in Air, Water, and Liquid Organics

Little is known about the temperature dependence of electron transfer occurring at real metal surfaces. For iron surfaces scratched in seven environments, we report Arrhenius activation energies obtained from the data of photoelectron emission (PE) and X-ray photoelectron spectroscopy (XPS). The environments were air, benzene, cyclohexane, water, methanol, ethanol, and acetone. PE was measured using a modified Geiger counter during repeated temperature scans in the 25–339 °C range under 210-nm-wavelength light irradiation and during light wavelength scans in the range 300 to 200 nm at 25, 200, and 339 °C. The standard XPS measurement of Fe 2p, Fe 3p, O 1s, and C 1s spectra was conducted after wavelength scan. The total number of electrons counted in the XPS measurement of the core spectra, which was called XPS intensity, strongly depended on the environments. The PE quantum yields during the temperature scan increased with temperature, and its activation energies (ΔEaUp1) strongly depended on the environment, being in the range of 0.212 to 0.035 eV. The electron photoemission probability (αA) obtained from the PE during the wavelength scan increased with temperature, and its activation energies (ΔEαA) were almost independent of the environments, being in the range of 0.113–0.074 eV. The environment dependence of the PE behavior obtained from temperature and wavelength scans was closely related to that of the XPS characteristics, in particular, the XPS intensities of O 1s and the O2− component of the O 1s spectrum, the acid–base interaction between the environment molecule and Fe–OH, and the growth of non-stoichiometric FexO. Furthermore, the origin of the αA was attributed to the escape depth of hot electrons across the overlayer.