Cloud Chamber Research Articles

Measured distribution of cloud chamber tracks from radioactive decay: A new empirical approach to investigating the quantum measurement problem

Abstract Using publicly available video of a diffusion cloud chamber with a very small radioactive source, I measure the spatial distribution of where tracks start and consider possible implications. This is directly relevant to the quantum measurement problem and its possible resolution, and it appears never to have been done before. The raw data are relatively uncontrolled, leading to caveats that should guide future, more tailored experiments. Aspects of the results may suggest a modification to Born’s rule at very small wave function, with possibly profound implications for the detection of extremely rare events such as proton decay, but other explanations are not ruled out. Speculatively, I introduce two candidate small-wavefunction Born rule modifications: a hard cutoff and an offset model with a stronger underlying physical rationale. Track distributions from decays in cloud chambers represent a previously unappreciated way to probe the foundations of quantum mechanics and a novel case of wave functions with macroscopic signatures.

Nudging a Pseudo‐Science Towards a Science—The Role of Statistics in a Rainfall Enhancement Trial in Oman

SummaryAlthough cloud seeding is a commonly used and plausible method for rainfall enhancement, its practical efficacy has not been established for seeding of convective clouds with hygroscopic materials. Other methods of rainfall enhancement are viewed as much less plausible. Thus, although increased electrical charge has been shown to enhance precipitation in cloud chamber experiments, exactly how ionisation of clouds can increase rainfall in the open atmosphere remains conjectural. A trial of the efficacy of ionisation for rainfall enhancement in the Hajar Mountains of Oman was carried out over 2013–2018. This paper provides some background to this non‐mainstream approach to increasing rainfall, showing how statistical modelling of rainfall data might be used to nudge rainfall enhancement via ionisation towards a more scientifically acceptable status. Analysis of the data collected in the trial shows that ionisation led to a statistically significant enhancement in positive rainfall in gauges located up to 70 km downwind of the ionisers. A headline analysis specified prior to commencement of the trial resulted in an estimate of 16.23% enhancement relative to rainfall that would have fallen without any ionisation, while a more sophisticated after the event analysis increased this estimate to 17.64%.

Particle emissions from a modern heavy-duty diesel engine as ice nuclei in immersion freezing mode: a laboratory study on fossil and renewable fuels

Abstract. We studied ice-nucleating abilities of particulate emissions from a modern heavy-duty diesel engine using three different types of fuel. The polydisperse particle emissions were sampled during engine operation and introduced to a continuous-flow diffusion chamber (CFDC) instrument at a constant relative humidity RHwater=110 %, while the temperature was ramped between −43 and −32 ∘C (T scan). The tested fuels were EN 590 compliant low-sulfur fossil diesel, hydrotreated vegetable oil (HVO), and rapeseed methyl ester (RME); all were tested without blending. Sampling was carried out at different stages in the engine exhaust aftertreatment system, with and without simulated atmospheric processing using an oxidation flow reactor. In addition to ice nucleation experiments, we used supportive instrumentation to characterize the emitted particles for their physicochemical properties and presented six parameters. We found that the studied emissions contained no significant concentrations of ice-nucleating particles likely to be of atmospheric relevance. The substitution of fossil diesel with renewable fuels, using different emission aftertreatment systems such as a diesel oxidation catalyst, and photochemical aging of total exhaust had only minor effect on their ice-nucleating abilities.

A Linear Paul Trap without the use of the Transverse Quadrupole Field

A detailed experimental study has been conducted to demonstrate the efficient confinement of ions in the popular four-rod configuration of a linear Paul trap without exciting the transverse radio-frequency (rf) quadrupole field. The three-dimensional (3D) ion confinement is achieved with an identical rf voltage applied to the end electrodes. The optimum operating region is visualized in the stability tune diagram, which indicates that a large number of ions can be stored by adjusting a few fundamental parameters. The lifetime of an ion cloud in the present linear trap is over a second (corresponding to a million rf cycles), long enough for various practical applications. It is also shown through 3D numerical simulations that one can easily extract ions from the trap at a low loss rate below 10%.

Numerically simulated influence of positive ions on the propagation of a positive streamer initiated in an argon plasma jet

A plasma jet with inert working gas operates in a streamer discharge mechanism. The propagation behavior of streamers determines the distribution of active species, which play a key role in the applications of plasma jets. To make clear streamer behavior under the influence of residual positive ions, a two-dimensional fluid model based on the continuity, the conservation, and Poisson's equations is employed to numerically investigate the dynamic behavior of a positive streamer when it approaches a cloud of positive ions with different densities and scales. Results indicate that the streamer always propagates along the axis and passes through the cloud of positive ions if the ions are rarefied (1.0 × 1016 m−3 in the core), which behaves like a free streamer. If the ion cloud has a medium density (5.0 × 1016 m−3 in the core), the streamer first deflects upward when it approaches the vicinity of the ion cloud and then deflects downward when it departs from the ion cloud, leaving a detouring track. The detouring track is also left if the ions are fairly dense (1.0 × 1017 m−3 in the core). However, the detouring process is fulfilled by the relay of two streamers, which are initiated at the jet nozzle and inside the ion cloud, respectively. Moreover, the velocity of the streamer is simulated with varying ion densities, voltage amplitudes, and gap widths. In addition, the deflection amplitude of the detouring track is investigated as a function of the voltage amplitude, gap width, ion density, cloud position, and cloud scale.

Real-time defects detection for apple sorting using NIR cameras with pruning-based YOLOV4 network

In order to realize on-line detection of defective apples on a two-lane fruit sorting machine, an inspection module was constructed using NIR cameras and a diffuse illumination chamber. A real-time apple defects inspection method was proposed based on YOLO V4 deep learning algorithm. The input images were generated by combining NIR images in three consecutive rubber roller stations. Channel pruning and layer pruning methods were used to simplify the YOLO V4 network and accelerate the detection speed. A non-maximum suppression (NMS) method based on L1 norm is proposed to remove redundant prediction box after fine-tuning the pruned network. The test results indicated that the model size and inference time of the pruning-based YOLO V4 network was decreased by 241.24 megabyte (MB) and 10.82 ms, respectively, and the mean average precision (mAP) was increased from 91.82% to 93.74%, compared with the YOLO V4 network before pruning. The pruning-based YOLO V4 network based on NIR images was not affected by the variation of skin color and suitable for detects identification of different cultivars including ‘Fuji’ apple covered in red-yellow striping and red blush, ‘Golden Delicious’, and ‘Granny Smith’, with the average detection accuracy of 93.9% at the on-line test assessing five fruit per second. The overall results showed that the proposed pruning-based YOLO V4 network combined with the developed inspection module, had great potential to be implemented in commercial fruit packing line for fruit defects identification.

High resolution track matching in a hybrid SciFi-emulsion detector

The paper describes the matching of tracks in a nuclear emulsion detector interleaved with scintillating optical fiber (SciFi) planes. This technology is planned to be used in the Scattering and Neutrino Detector (SND) of the new experiment SHiP (Search for Hidden Particles) being developed in CERN. The experiment SHiP aimed on the search of very weakly interacting particles in the poorly studied region of the particle masses below 10 GeV will be installed in a beam dump facility at the Super Proton Synchrotron (SPS). The SND detector is aimed to provide temporal and spatial analysis of the particle showers and isolated tracks to separate and reconstruct events in nuclear emulsion. SND design includes emulsion cloud chamber (ECC) and SciFi tracker. Motivation for using the combination of ECC and SciFi is to obtain the “real-time” information for the prompt and high-accuracy event analysis. The algorithm presented in the article provides a track matching accuracy not less than 50 μm with an efficiency of (89±8)%.

Characterisation of the Manchester Aerosol Chamber facility

Abstract. This study describes the design of the Manchester Aerosol Chamber (MAC), initially developed in 2005 and presents for the first time its comprehensive characterisation. The MAC is designed to investigate multi-phase chemistry and the evolution of aerosol physico-chemical properties from the real-world emissions (e.g. diesel engine, plants) or of secondary organic aerosol (SOA) produced from pure volatile organic compounds (VOCs). Additionally, the generated aerosol particles in the MAC can be transferred to the Manchester Ice Cloud Chamber (MICC), which enables investigation of cloud formation in warm, mixed-phase, and fully glaciated conditions (with temperature, T, as low as −55 ∘C). The MAC is an 18 m3 fluorinated ethylene propylene (FEP) Teflon chamber with the potential to conduct experiments at controlled temperature (15–35 ∘C) and relative humidity (RH; 25 %–80 %) under simulated solar radiation or dark conditions. Detailed characterisations were conducted at common experimental conditions (25 ∘C, 50 % RH) for actinometry and determination of background contamination, wall losses of gases (NO2, O3, and selected VOCs), aerosol particles at different sizes, chamber wall reactivity, and aerosol formation. In addition, the influences of chamber contamination on the wall loss rate of gases and particles and the photolysis of NO2 were estimated.

Ion energy distribution in an electron beam ion trap inferred from simulations of the trapped ion cloud.

We have inferred the energy distribution of trapped ions in an electron beam ion trap (EBIT) from simulations of the spatial distribution of Fe^{13+} ions and a comparison with measured visible light images of the ion cloud. We simulated the cloud of Fe^{13+} ions by computing ion trajectories in the EBIT for different ion energy distributions used to initialize the trajectories. We then performed a least-squares fit to infer the ion energy distribution that best reproduced the measured ion cloud. These best-fit distributions were typically non-Maxwellian. For electron beam energies of 395-475eV and electron beam currents of 1-9 mA, we find that the average ion energy is in the range of 10-300eV. We also find that the average ion energy increases with increasing beam current approximately as 〈E〉≈25I_{e}eV, where I_{e} is the electron beam current in mA. We have also compared our results to Maxwell-Boltzmann-distribution ion clouds. We find that our best-fit non-thermal distributions have an 〈E〉 that is less than half that of the T from the best-fit Maxwell-Boltzmann distributions (〈E〉/q)/T=0.41±0.05.

New investigations on homogeneous ice nucleation: the effects of water activity and water saturation formulations

Abstract. Laboratory measurements at the AIDA cloud chamber and airborne in situ observations suggest that the homogeneous freezing thresholds at low temperatures are possibly higher than expected from the so-called “Koop line”. This finding is of importance, because the ice onset relative humidity affects the cirrus cloud coverage and, at the very low temperatures of the tropical tropopause layer, together with the number of ice crystals also the transport of water vapor into the stratosphere. Both the appearance of cirrus clouds and the amount of stratospheric water feed back to the radiative budget of the atmosphere. In order to explore the enhanced ice onset humidities, we re-examine the entire homogeneous ice nucleation process, ice onset, and nucleated crystal numbers, by means of a two-moment microphysics scheme embedded in the trajectory-based model (CLaMS-Ice) as follows: the well-understood and described theoretical framework of homogeneous ice nucleation includes certain formulations of the water activity of the freezing aerosol particles and the saturation vapor pressure of water with respect to liquid water. However, different formulations are available for both parameters. Here, we present extensive sensitivity simulations testing the influence of three different formulations for the water activity and four for the water saturation on homogeneous ice nucleation. We found that the number of nucleated ice crystals is almost independent of these formulations but is instead sensitive to the size distribution of the freezing aerosol particles. The ice onset humidities, also depending on the particle size, are however significantly affected by the choices of the water activity and water saturation, in particular at cold temperatures ≲205 K. From the CLaMS-Ice sensitivity simulations, we here provide combinations of water saturation and water activity formulations suitable to reproduce the new, enhanced freezing line.

Improving the Wilson Cloud Chamber Using Peltier Chips

The Wilson cloud chamber is an apparatus used for detecting and observing the trails of alpha/beta rays or even cosmic rays in saturated gas conditions. The principle of this device is based upon the powerful ionization of the aforementioned rays within the medium. This article will provide instruction for creating a classic version of the cloud chamber using a glass food container and dry ice. Some common malfunctions and disadvantages of the classic version will be discussed. Moreover, this article will introduce an improvement of the cloud chamber using the Peltier chip as an alternative for dry ice, and also compare the pros and cons of these two methods.

ANALYSIS OF THE INFLUENCE OF PROLONGED IRRADIATION ON HEMATOPOIETIC PROGENITOR CELLS IN GEL DIFFUSION CHAMBERS USING MATHEMATICAL MODELLING.

determining of the functional activity of mice bone marrow hematopoietic progenitor cells, cultivated in gel diffusion chambers, on the stages of hematopoiesis recovery after their prolonged irradiation in the lethal dose in a comparative aspect with the method of colony forming in spleen using mathematical model. The method of cell cultivation in gel diffusion chambers, cytological methods, mathematical modeling, and statistical methods of research were used. Bone marrow samples extracted from the femur of mice irradiated with a total dose of 8 Gy with a power 0.0028 Gy/min were cultivated in diffusion chambers with semi solid agar in the abdominal cavity of CBA recipient mice. Comparative analysis of the colonyforming efficiency of progenitor cells (CFU) was carried out during cultivation in gel diffusion chambers in the process of hematopoiesis recovery for 30 days, as well as in the spleen of lethally irradiated animals, in accordance with the mathematical model. Analysis of colony forming kinetics in gel diffusion chambers after prolonged exposure to ionizing radiation indicated the biphasic nature of hematopoiesis recovery. Thus, in the first few days after the irradiation a drop in the number of CFU is observed compared to the control, which continues until the 9th day. Subsequently there is a sharp increase in the number of CFU in cell culture, which continues until the complete recovery of hematopoiesis. The obtained data, recalculated per mouse femur, correspond to the results of colony forming in the spleen of irradiated animals, described by K. S. Chertkov and taken as a basis while developing our mathematical model, as well as to its parameters, which describe the process of hematopoiesis recovery. Conformity of the indices obtained during the cultivation using the method of gel diffusion chambers of mice bone marrow prolongedly irradiated at a total dose of 8 Gy with a power 0.0028 Gy/min, to the results of colony forming in spleen of lethally irradiated mice, which were the basis for mathematical model development, is the evidence of the feasibility of using a mathematical model to assess the process of hematopoiesis recovery by progenitor cells of different maturation levels, and the experimental approach of CFU growing in gel diffusion chambers can be considered as an additional method of researching the hematopoiesis recovery along with the spleen colony method.

GRAPES: semi-automatic approach for forecasting models to predict GameStop prices using cloud computing and machine learning

GRAPES: semi-automatic approach for forecasting models to predict GameStop prices using cloud computing and machine learning

Blockchain and IoT for Personal and Physical Security

The Internet of Things connects intelligent physical objects (things) and people. IoT enables every “Thing” to connect and interact, creating and transferring massive amounts of data. Because IoT de-vices handle so much data, it became necessary to incorporate Cloud Computing, Machine Learning, and Information Modelling. The significant rise in IoT is creating a surge in ICT business. By 2020, 95% of new goods will include IoT at their heart. As can be seen, IoT items will be more pre-sent, raising concerns about their visibility on the internet and legal access to resources. Innovating apps that improve a person's physical and personal life are enabled by IoT, but people's lack of security and susceptibility may lead to serious concerns like home security being penetrated and centralized organisations employing sensitive data being hacked. Blockchain technology is getting widespread interest and investigation because to its remarkable solutions to the challenges connected with the traditional centralized IoT architecture. Because there are so many IoT devices on the mar-ket for enhancing physical and mental health, and overall quality of life, a distributed trust platform that ensures scalability, privacy, and reliability is required. Integration of IoT and BC is a complex task. This research paper's goal is to create an IOT and Blockchain Application Environment that will improve a person's personal and physical existence. Thus, our main emphasis will be on developing a secure and safe Smart Home. Our suggested design uses a hierarchical and distributed blockchain platform to preserve security and privacy while meeting IoT needs. Thus, we have linked home automation with physical health, assuring safety, convenience, and health.

Morphofunctional Features of Hematopoietic Bone Marrow Progenitor Cells in Patients with Chronic Myeloid Leukemia in Long-Term Culture of Gel Diffusion Chambers In Vivo

Morphofunctional Features of Hematopoietic Bone Marrow Progenitor Cells in Patients with Chronic Myeloid Leukemia in Long-Term Culture of Gel Diffusion Chambers In Vivo

An Approach to the Measurement of Radon Permeability and Transmission Factor Using Cr-39 Detectors Inside a Diffusion Chambers Exposed in a New-Build Radon Chamber

An Approach to the Measurement of Radon Permeability and Transmission Factor Using Cr-39 Detectors Inside a Diffusion Chambers Exposed in a New-Build Radon Chamber

Menthol in Combination with Iontophoresis Promotes Natamycin Penetration through the Cornea: In Vitro and In Vivo Studies.

We studied whether menthol can promote penetration of natamycin, a representative antifungal macrolide agent, through the cornea. Natamycin penetration was examined using an in vitro iontophoresis system that simulates clinical scenario; menthol (0.1-0.3%, w/v) was added to the donor reservoir of a standard Franz diffusion chambers. In vivo effects of menthol on natamycin penetration were examined in a set of bioassays using rabbits inoculated with Aspergillus fumigatus in the right eye. Potential irritation to the rabbit eye was examined using a standard test. Menthol significantly (p<0.05) potentiated the effects of iontophoresis on natamycin penetration. The optimal combination seemed to be 0.2% menthol in combination with 3 mA/cm2 iontophoresis.

Electron vortexes in two-dimensional steady photoplasma

This paper reports the new phenomenon – the presence of electron vortexes in steadily generated two-dimensional photoplasma. A fluid model of a two-chamber photoplasma cell with sodium vapor and Argon as a buffer gas has been conducted in this study. The excitation source is in the first (driver) chamber. The transport processes of the generated plasma from the first into the second (diffusion) chamber create an electromotive force (EMF), which is the potential difference between them. It is shown that, in the two-chamber photoplasma, along with the flows of classical ambipolar diffusion, vortex currents of electrons are also formed. The change in temperature and electron density caused by them could affect the potential difference between the two chambers. The dependence of the current vortices and, consequently, the generated EMF on the buffer gas pressure is shown.

A frequency-aware management strategy for virtual machines in DVFS-enabled clouds

It is demanding to curtail energy consumption of virtual-machine-powered data centers, because modern data centers have been significantly scaling up in capacity in past decades. In this study, we propose a frequency-aware management strategy, which controls dynamic power and static power of processors running virtual machines in data centers. Unlike existing dynamic voltage and frequency scaling schemes, our strategy simply incorporates frequency requirements rather than task execution times. This salient feature is practical, because task execution times in a raft of real-world applications are unknown in a priori. We build a frequency-aware model, which is adept at deriving an optimal frequency ratio that minimizes processors’ energy consumption. With our model in place, the energy efficiency of a data center can be maximized by adjusting the processor's frequency to meet the optimal frequency ratio. We design a management approach to judiciously adjust frequency ratio to conserve energy without violating the frequency requirements imposed by virtual machines. After analyzing the correlations between frequency ratio and energy consumption, we show that a small static power proportion gives rise to high energy-saving performance. The results demonstrate that our model lays out a solid theoretical foundation catering to the development of power management software in DVFS-enabled clouds.

Smart Architecture Energy Management through Dynamic Bin-Packing Algorithms on Cloud

Smart Home Architecture is suitable for progressive and symmetric urbanization. Data being generated in smart home appliances using internet of things should be stored in cloud where computing resources can analyze the data and generate the decisive pattern within no time. This additional requirement of storage, majorly, comprising of unfiltered data escalates requirement of host machines which carries with itself extra overhead of energy consumption; thus, extra cost has to be beard by service providers. Various static algorithms are already proposed to improve energy management of cloud data centers by reducing number of active bins. These algorithms are not able to cater to the needs of present heterogeneous requests generated in cloud machines by people of diversified work environment with adhering to the requirements of quality parameters. Therefore, the paper has proposed and implemented dynamic bin-packing approaches for smart architecture that can significantly reduce energy consumption without compromising upon makespan, resource utilization and Quality of Service (QoS) parameters. The novelty of the proposed dynamic approaches in comparison to the existing static approaches is that the proposed approach dynamically creates and dissolves virtual machines as per incoming and completed requests which is a dire need of present computing paradigms via attachment of time-frame with each virtual machine. The simulations have been performed on JAVA platform and dynamic energy utilized-best fit decreasing bin packing technique has produced better results in maximum runs.