Please Help Quantify X-Rays
Posted: Mon Dec 03, 2018 6:19 pm
Hello All,
My name is Sam, I've been a lurker here for a couple of years, but this is my first true post (aside from Introduce Yourself). I am the team lead of the University of Portland IEC Fusor Capstone team on campus, a project I proposed. Our team consists of 4 senior Mechanical Engineering students and our Adviser,a PhD in Mechanical Engineering with expertise in thermodynamics and combustion. I preface this because so far as we know there is no one at our school with significant experience in nuclear fusion (or nuclear power/science).
Our fusor design consisted of:
- 20kV power supply at 35mA
- KF-50 S.S. 5-way cross (with one viewport)
- 1inch Dia. Tantalum grid
- Remote power control for emergency shut-off
- Vented exhaust from the mechanical and diffusion pump
- Operating distance of at least 15ft (could be increased)
- nuetron detector (either BD or GS-Neutron-150)
- GM dosimeter (although we had not identified a specific one)
You may have critiques or questions of our design decisions, and I would love to hear them, but first... Initially, our project was supported and fully funded. However, some in our Engineering Department learned that fusors produce x-rays and "nuclear waste" (Tritium) and our project was put on hard stop (know we never tried to hide any of these things). Our team has been working very hard to dispel rumors everything from "cold fusion", "radioactive deuterium", "nuclear waste", "radiated chamber", and more. It is clear that fearful decision making took the place of logical scientific discussion.
Despite our efforts, our school decided to dispose of our deuterium lecture bottle, and has said we may proceed with construction but will not fuse. This has been very disheartening for our team. Regardless of whether or not our fusor is ever turned on, I would like to prove in our project reports and presentations that x-rays and other forms of radiation would not have been a serious safety risk. My teammate and I have been working hard on this, and based off data take from Stano, Michal and Raèko, Michal [1] were able to estimate our total tritium production. But we've had a much slower time trying to approximate x-rays. I have scoured Google Scholar for academic information on x-rays emitted from IEC machines and only find very generic info like "not enough to be a concern". The only hard evidence we have found has been MATLAB code developed by the Eindhoven University of Technology [2] to determine the x-ray spectrum, intensity, penetration depth, and total energy. We have been slowly adapting the code as we attempt to teach ourselves radiation science.
With all of that, would anyone be able to offer help in proving that x-rays are not a concern? Maybe I'm wrong, maybe at the power we planned (we've also now lowered our power to 13kV 30mA from a neon sign transformer) they would be a health risk, but all that I've read (which has been a lot) from here and all the scholarly articles on IEC machines I can find say they would not. But how can we provide our administration with reassurance without holding a dosimeter to a working machine? Would any of you have dosimetry data from some of your runs? Any data, resources, ideas, you can provide would be extremely appreciated.
One of the reasons we started this project was to help educate people to fight the stigma against nuclear power, now that stigma, not scientific discussions that are holding us back.
Thanks for all your help,
Sam
[1] Stano, M., & Raèko, M. (2016). Experiments on D-D Fusion Using Inertial Electrostatic Confinement ( IEC ) Device in the Laboratory Exercises on
Plasma Physics at the Comenius University *. Acta Physica Universitatis Comenianae, LIII, 71–81. https://doi.org/10.1037/0278-6133.10.2.80
[2] Minderhout, V. (n.d.). Photon radiation produced by the fusor theoretical model and measurements. Retrieved from
https://pure.tue.nl/ws/files/67736677/850820-1.pdf
EDIT 1: Spelling
My name is Sam, I've been a lurker here for a couple of years, but this is my first true post (aside from Introduce Yourself). I am the team lead of the University of Portland IEC Fusor Capstone team on campus, a project I proposed. Our team consists of 4 senior Mechanical Engineering students and our Adviser,a PhD in Mechanical Engineering with expertise in thermodynamics and combustion. I preface this because so far as we know there is no one at our school with significant experience in nuclear fusion (or nuclear power/science).
Our fusor design consisted of:
- 20kV power supply at 35mA
- KF-50 S.S. 5-way cross (with one viewport)
- 1inch Dia. Tantalum grid
- Remote power control for emergency shut-off
- Vented exhaust from the mechanical and diffusion pump
- Operating distance of at least 15ft (could be increased)
- nuetron detector (either BD or GS-Neutron-150)
- GM dosimeter (although we had not identified a specific one)
You may have critiques or questions of our design decisions, and I would love to hear them, but first... Initially, our project was supported and fully funded. However, some in our Engineering Department learned that fusors produce x-rays and "nuclear waste" (Tritium) and our project was put on hard stop (know we never tried to hide any of these things). Our team has been working very hard to dispel rumors everything from "cold fusion", "radioactive deuterium", "nuclear waste", "radiated chamber", and more. It is clear that fearful decision making took the place of logical scientific discussion.
Despite our efforts, our school decided to dispose of our deuterium lecture bottle, and has said we may proceed with construction but will not fuse. This has been very disheartening for our team. Regardless of whether or not our fusor is ever turned on, I would like to prove in our project reports and presentations that x-rays and other forms of radiation would not have been a serious safety risk. My teammate and I have been working hard on this, and based off data take from Stano, Michal and Raèko, Michal [1] were able to estimate our total tritium production. But we've had a much slower time trying to approximate x-rays. I have scoured Google Scholar for academic information on x-rays emitted from IEC machines and only find very generic info like "not enough to be a concern". The only hard evidence we have found has been MATLAB code developed by the Eindhoven University of Technology [2] to determine the x-ray spectrum, intensity, penetration depth, and total energy. We have been slowly adapting the code as we attempt to teach ourselves radiation science.
With all of that, would anyone be able to offer help in proving that x-rays are not a concern? Maybe I'm wrong, maybe at the power we planned (we've also now lowered our power to 13kV 30mA from a neon sign transformer) they would be a health risk, but all that I've read (which has been a lot) from here and all the scholarly articles on IEC machines I can find say they would not. But how can we provide our administration with reassurance without holding a dosimeter to a working machine? Would any of you have dosimetry data from some of your runs? Any data, resources, ideas, you can provide would be extremely appreciated.
One of the reasons we started this project was to help educate people to fight the stigma against nuclear power, now that stigma, not scientific discussions that are holding us back.
Thanks for all your help,
Sam
[1] Stano, M., & Raèko, M. (2016). Experiments on D-D Fusion Using Inertial Electrostatic Confinement ( IEC ) Device in the Laboratory Exercises on
Plasma Physics at the Comenius University *. Acta Physica Universitatis Comenianae, LIII, 71–81. https://doi.org/10.1037/0278-6133.10.2.80
[2] Minderhout, V. (n.d.). Photon radiation produced by the fusor theoretical model and measurements. Retrieved from
https://pure.tue.nl/ws/files/67736677/850820-1.pdf
EDIT 1: Spelling