TRONIC CLOUD CHAMBER - refrigeration based miniaturized cloud chamber

Abstract

The study of cosmic rays has always brought up interesting investigations. In physics, this topic has very active research. In 1924,Blackettand co-workers used the cloud chamber to observe the transmutation of nitrogen into fluorine, which then disintegrated into oxygen[1]. Anderson and co-workers in 1933 discovered anti-electron, the positron in cloud chamber[2]. In 1947 Rochester and Butler published the first cloud chamber images showing evidence for kaon [3]. When the modern particle accelerators were not invented, cloud chamber was a simple device and efficientmethod to study the cosmic particles[4]. The cloud chamber was further modified by Stuart Blackett, giving it more number of applications[5]. Cloud chambers operate with two methods which are liquid in the sealed box, and method of cooling [6].

The first cloud chamber was invented by Wilson in the year 1911[7]. Wilson investigated the effects of sunlight on the clouds around the mountain, and reproduced them in a laboratory. Wilson used X-rays for this study as the illumination wave. He observed minute streaks and patches of cloud throughout the region in the path of the beam. The clouds were mainly short thread-like objects, few of them moving in straight lines and some of them even looping round.Wilson saw this as a very direct proof that X-rays liberated energetic electrons in the gas, and that these electrons caused ionization along the path of the X-rays. Wilson modified his cloud chamber by 1912, and used it to produce many photographs of the alpha, beta and X-ray tracks. With his cooperation cloud chambers were manufactured commercially by the Cambridge Scientific Instruments Company, and remained the principle detector for studying particle tracks until the invention of the bubble chamber in the 1950s[8].

Using this instrument at CERN, FERMILAB experimental physicists have discovered many properties that shaped our understanding of quantum physics [9].

When a particle is passed through the supersaturated vapors, droplets are formed on the line due to ionization along the track and particle is detected is the principle behind Wilson’s cloud chamber [7]. However tronic cloud chamber is based on the refrigeration principle where in a coolant is circulated through the system which efficiently transfers heat from the region to be cooled and dissipates it through the condenser according to thermodynamic principle[10].

The method of cooling has been used as experiments in this study. Modern magnetic techniques influence the flow of liquid in the sealed box in such a way that it reaches super saturation state. Alternatively, there is dry ice which is commonly used to cool it down. Magnetic techniques don’t help much as they require a constant supply of electricity. This limits the study at an isolated place where cosmic radiations of interest are present. Further, even with the supply of electricity, the experiment is tampered with particles knocked off from the wires hence limiting the possibility of studying cosmic particles [11].Further, it has been found that dry ice is not eco-friendly, since at the lower temperature it has to be handled carefully and also sublimates quickly[12].

No work has been done till now to solve these two issues. In this study, we have developed a novel method to address these problems with an application of engineering tools to cool it in a miniature scale. The usability of this method limits above micro scale cooling. The method uses refrigeration principle as basis and combined with other thermodynamic properties helps cool the system more efficiently and much lower temperature can be attained relative to the original invention .The miniature device ensures that it is easy to carry and experiment can be conducted in isolated conditions ensuring the study of cosmic rays.  The next section describes the experiments performed in this study.