Luminous Tritium Jewelry

## Fusion Reactor

Over the course of my senior year in high school, I spent over 1,000 hours building a fusion reactor in my bedroom. The construction of the reactor was the most challenging project I have ever attempted. My original reason for initiating the project was because of its complexity. I wanted to learn about as many scientific fields as possible. Fusion was the ideal contender, promising to teach me the fundamentals of nuclear and plasma physics, mechanical and electrical engineering, and the behavior of high voltage currents. As I progressed with my research on nuclear fusion and the specific method in which I would achieve it, I realized that the reason behind my motivation was changing. What began as a quest for knowledge became the calling of a passion.

Neutron Bubble Dosimeter

When two deuterium nuclei fuse inside my reactor, there is an equal probability for two different reactions to occur. One of the reaction produces a tritium nucleus and a hydrogen nucleus while the other reaction produces a helium three nucleus and ejects a high energy neutron also called a fast neutron. To prove that I was fusing atoms, I used a neutron bubble dosimeter to detect fast neutrons generated by my reactor. The dosimeter contains small droplets of a fluid suspended in a gel that will vaporize when struck by fast neutrons. The vaporized liquid forms visible bubbles that when counted, can be used to calculate the neutron radiation dose experienced by the detector. This dose can then be used to calculate the total neutron flux which determines the rate of fusion and the number of atoms synthesized in the reactor during a given period. These numbers are useful as they allow me to conduct experiments to improve the rate of fusion within my reactor. I am currently developing several experiments that will hopefully demonstrate increased rates of fusion that are statistically significant to the control tests. I will now explain my method of calculating these values below.

Operation voltage: $$-30~kV$$

Operation current: $$5~mA$$

Operation pressure: $$10~mTorr$$

Duration of experimental test: $$\frac{1}{3}~hours$$

Bubbles generated in detector: $$24~bubbles$$

Sensitivity of detector: $$29~bubbles/mrem$$

Distance between detector and ideal neutron source: $$15~cm$$

By taking the quotient of the number of bubbles $$b$$ and the sensitivity $$s$$ of the detector, the dose of neutron radiation $$d$$ can be calculated:

$$d=\frac{b}{s}=\frac{24~bubbles}{29~bubbles/mrem}=0.83~mrem$$

Because all the neutrons emitted from my reactor are generated by a single type of reaction, they all share the same kinetic energy (specifically $$2.45~MeV$$). The calculated radiation dose due to mono-energetic neutrons can be converted to a neutron flux $$\phi$$ if divided by the time of exposure $$t$$ and multiplied by a flux to dose rate constant $$\mu$$. The flux to dose rate constant that corresponds with $$2.45~MeV$$ neutrons is about $$8$$ as indicated on page 46 of this document by Sandia National Laboratories. The calculated neutron flux is approximated to cover the area of $$1~cm^2$$ as it is only representative of the neutrons that pass through the detector.

$$\phi=\frac{d}{t}\cdot \mu=\frac{0.83~mrem}{1/3~hours}\cdot 8~\frac{\frac{neutrons/cm^2}{second}}{mrem/hour}=20~\frac{neutrons/cm^2}{second}$$

To calculate the total neutron emission rate $$\Phi$$, the neutron flux at the detector must be integrated over a surface that encloses the neutron source. To accomplish this, I can use a sphere with a radius identical to the distance between the ideal neutron source (the center of the reactor) and the detector. It is important to note that I am assuming isotropic neutron emission (when neutrons are emitted in all directions in equal proportions).

$$\Phi=\phi\oint dA=20~\frac{neutrons/cm^2}{second}\cdot 4\pi (15~cm)^2=5.7\times 10^4~\frac{neutrons}{second}$$

Determining the rate of fusion $$F$$ is as simple as doubling the isotropic neutron emission rate. This is because one neutron is generated by the reactor for every two fusions due to the probability of the reactions.

$$F=2\cdot \Phi=1.14\times 10^5~\frac{fusions}{second}$$

To find the number of atoms synthesized $$a$$, I can take the product of the rate of fusion and the time. The final value of atoms synthesized is comprised of $$50\%$$ helium three atoms and $$50\%$$ tritium atoms.

$$a=F\cdot t=1.14\times 10^5~\frac{fusions}{second}\cdot 1.2\times 10^3~seconds=1.37\times 10^8~atoms$$

### Fusion Research Projects in Progress

• Investigate the significance of deuterium embedment on the rate of fusion- When the reactor is operated, deuterium molecules are embedded in the walls of the vacuum vessel. The amount of deuterium embedded in the chamber walls is largely dependent on the wall material. I have observed the rate of fusion in my reactor to increase from continued operation. I am confident this increase in the fusion rate is due to deuterium embedment in the chamber walls, which causes increased beam-on-target fusions and higher deuteron energy as the ions are accelerated through a greater potential to the cathode when they are released from the chamber wall. For each iteration of the experiment, I will coat the chamber walls with a different metal that varies in its ability to store deuterium. After a fixed period of deuterium loading, I will record the reactor's rate of fusion. I hypothesize that the rate of fusion will increase when the vacuum vessel is coated with metals (such as palladium) that are known to store hydrogen more readily than steel or aluminum.
• Determine methods to reduce plasma instabilities- Plasma instabilities during operation at potentials greater in magnitude than $$-30~kV$$ often cause the fusion plasma to extinguish. This prevents operation at the preferred potential of $$-40~kV$$, which would cause an increase in the rate of fusion. I will use electromagnets arranged symmetrically about the cathode to apply external magnetic fields to the fusion plasma. I hypothesize that the magnetic fields will prevent plasma beams from colliding with the vacuum vessel while increasing the general symmetry of the fusion plasma, which will allow stable fusion tests at higher potentials.

## Visit to MIT

On December 12, 2016, I visited MIT to familiarize myself with the campus and meet faculty members with whom I have established communication. First, I met with Professor Dennis Whyte, head of Nuclear Science and Engineering and director of the PSFC (Plasma Science and Fusion Center). After taking a guided tour of the campus, I met with Professor Michael Short, director of undergraduate Nuclear Science and Engineering. The next day, I visited the Alcator C-Mod fusion reactor at the PSFC where I was guided by Alex Creely, a graduate student studying nuclear fusion. I then visited Professor Short's laboratory where graduate students Reid Tanaka and Cody Dennett showed me around and explained the various experiments taking place. The following day, I attended the Nuclear Science and Engineering Senior Design Competition by the invitation of Professor Short. My visit to MIT was an incredible experience. Being around so many kind and passionate individuals was inspiring.

Irradiant Designs is my current project that combines my skill in 3D design with my love of nuclear science. Visit the other tabs of this website for more information.

## Jazz Piano

I have been playing piano for most of my life. Here is recent recording.

## Tesla Coils

Over the past several years, I have built three Tesla coils including a standard spark gap Tesla coil, a rotary spark gap Tesla coil, and an audio modulated double resonant solid state Tesla coil that can play a polyphonic tone by vibrating the air with its plasma bolts when given a MIDI signal.

## Carbon Dioxide Laser Turret

I built a 40 watt carbon dioxide laser turret that can burn wood at a range of 15 feet. Because the laser tube is mounted on a TV wall mount, it can swivel right and left as well as up and down. The handle is designed in such a way that both switches must be pressed simultaneously for the power supply to activate.

## Other Science Projects

Here are a few other fun science projects I did throughout my high school career.

## Berkeley High 3D Modeling and Printing Club

During my sophomore year in high school, I founded the Berkeley High 3D Printing and Modeling Club. One day a week, I gave an hour-long lesson, teaching members how to design their models and export them for printing. I also taught more advanced topics including animation, standard physics simulations, fluid simulations, cloth and particle simulations, and photo-realistic rendering.