First Fusion Claim for Jack and Scott's Fusor
Posted: Mon Aug 31, 2015 11:13 pm
Written Overview:
Neutron Detection- For our neutron detection we currently use a LND-2520 Helium 3 Proportional Counter with a NVTH value of 21 cps/nv. This probe is driven by a Johnson model 10 rate meter. This rate meter is very similar to a ludlum model 3 as it has an adjustable voltage within the range of 500-1500 volts. Here is the data sheet for this specific detector:
http://www.lndinc.com/products/539/
Vacuum System- For our vacuum system we have a 1 CFM mechanical pump backing a Varian HS2, which pumps at 285 L/s. Directly after our mechanical pump we have a bellows valve for the ability to throttle our mechanical pump down. Another bellows valve can be seen directly after the Varian HS2 for the ability to isolate the main reaction chamber (KF50 5-way cross) entirely. To measure our pressure inside the chamber we have a Thermocouple gauge and controller. We are having troubles with these as it “bottoms out” at ~25 mTorr. Scott and I are not inclined to believe this as we would be able to see a plasma at 25 mTorr and we do not. We are inclined to believe that the operational pressure of “30-40 mTorr” (using numbers off of the controller) is actually somewhere between 10-20 mTorr based of off the plasma star we are seeing and the evidence of neutrons.
Gas system- The gas system is composed of a 10 liter lecture bottle of 99.8% deuterium gas purchased from Sigma Aldrich. Following the lecture bottle is a gas regulator with a variable pressure between 0 and 30 psi. Next, we have a ¼” swagelok shut off valve followed by an ss-ss4 fine metering valve.
High voltage: The two main power supplies we are using for this fusor are a Glassman 30kV 32mA and a Glassman 40kV 7.5mA. The 40kV model required us to build our own controller to provide a 0-10 voltage reference to the supply. Our controller is currently allowing us to fully vary the voltage from 0-40kV, however the panels are not reading accurately. For this reason, the primary power supply we are using for our data collection in this post is the 30kV 32mA supply. In line with the high voltage we have three resistors that are wired in series in order to ballast the power supply. These three resistors add up to a value of 95kOhm at 200 watts.
X ray Detection: In order to detect x rays being emitted from the viewport and to ensure that scattering is minimal as well as no leakage from the stainless steel chamber we have a traditional geiger counter (CRM 100-we understand that this is not traditionally suitable for detection) and a ludlum model 3 with a pancake probe.
In the following video we provide a 4 minute overview of the system:
https://www.youtube.com/watch?v=DDcP2-fkZ4w
Data collected from run:
Date of run: August 31, 2015
Time: 11:36 AM
Operators: Jack Rosky and Scott Moroch
Average voltage: 25-28kV
Average current: 8-10mA
Pressure: 35 milliTorr (see above description for further details on this specific value)
Neutron counts (cpm) with 3He probe: 150 cpm
Moderator: Low Density of Polyethylene
Distance from center of chamber: 8” (~20cm)
Average Background Count on Detector: Effectively 0 cpm (1- 2 counts every 5 minutes or so)
Cathode material: Hafnium
Cathode shape: Spherical (2 loop)
In the following two videos we demonstrate the neutron counts observed as well as the effect of pulling the tube from the moderator
https://www.youtube.com/watch?v=DtrpxRjAcmA
https://www.youtube.com/watch?v=P6wjKpiDThE
In the following video we show the plasma and x rays from our camera: Note: The starmode beams and red hue are not as prominent in the video as they are in person. The camera is an old iPhone 4 front facing camera- hence the poor quality.
https://www.youtube.com/watch?v=tRTbC3aDOMo
After nearly two years of work on this fusor, it is at this time that we would like to request admittance into the neutron club. If the above data, videos and descriptions do not meet the requirements of the neutron club, we would be more than happy to collect further data to support our claims in the near future.
Sincerely,
Jack Rosky and Scott Moroch
P.S. We would like to thank everyone here on the fusor.net community as well as those on eBay who kindly donated some of the parts. We would never have been able to accomplish this without the help from all of you. Thank you!
Neutron Detection- For our neutron detection we currently use a LND-2520 Helium 3 Proportional Counter with a NVTH value of 21 cps/nv. This probe is driven by a Johnson model 10 rate meter. This rate meter is very similar to a ludlum model 3 as it has an adjustable voltage within the range of 500-1500 volts. Here is the data sheet for this specific detector:
http://www.lndinc.com/products/539/
Vacuum System- For our vacuum system we have a 1 CFM mechanical pump backing a Varian HS2, which pumps at 285 L/s. Directly after our mechanical pump we have a bellows valve for the ability to throttle our mechanical pump down. Another bellows valve can be seen directly after the Varian HS2 for the ability to isolate the main reaction chamber (KF50 5-way cross) entirely. To measure our pressure inside the chamber we have a Thermocouple gauge and controller. We are having troubles with these as it “bottoms out” at ~25 mTorr. Scott and I are not inclined to believe this as we would be able to see a plasma at 25 mTorr and we do not. We are inclined to believe that the operational pressure of “30-40 mTorr” (using numbers off of the controller) is actually somewhere between 10-20 mTorr based of off the plasma star we are seeing and the evidence of neutrons.
Gas system- The gas system is composed of a 10 liter lecture bottle of 99.8% deuterium gas purchased from Sigma Aldrich. Following the lecture bottle is a gas regulator with a variable pressure between 0 and 30 psi. Next, we have a ¼” swagelok shut off valve followed by an ss-ss4 fine metering valve.
High voltage: The two main power supplies we are using for this fusor are a Glassman 30kV 32mA and a Glassman 40kV 7.5mA. The 40kV model required us to build our own controller to provide a 0-10 voltage reference to the supply. Our controller is currently allowing us to fully vary the voltage from 0-40kV, however the panels are not reading accurately. For this reason, the primary power supply we are using for our data collection in this post is the 30kV 32mA supply. In line with the high voltage we have three resistors that are wired in series in order to ballast the power supply. These three resistors add up to a value of 95kOhm at 200 watts.
X ray Detection: In order to detect x rays being emitted from the viewport and to ensure that scattering is minimal as well as no leakage from the stainless steel chamber we have a traditional geiger counter (CRM 100-we understand that this is not traditionally suitable for detection) and a ludlum model 3 with a pancake probe.
In the following video we provide a 4 minute overview of the system:
https://www.youtube.com/watch?v=DDcP2-fkZ4w
Data collected from run:
Date of run: August 31, 2015
Time: 11:36 AM
Operators: Jack Rosky and Scott Moroch
Average voltage: 25-28kV
Average current: 8-10mA
Pressure: 35 milliTorr (see above description for further details on this specific value)
Neutron counts (cpm) with 3He probe: 150 cpm
Moderator: Low Density of Polyethylene
Distance from center of chamber: 8” (~20cm)
Average Background Count on Detector: Effectively 0 cpm (1- 2 counts every 5 minutes or so)
Cathode material: Hafnium
Cathode shape: Spherical (2 loop)
In the following two videos we demonstrate the neutron counts observed as well as the effect of pulling the tube from the moderator
https://www.youtube.com/watch?v=DtrpxRjAcmA
https://www.youtube.com/watch?v=P6wjKpiDThE
In the following video we show the plasma and x rays from our camera: Note: The starmode beams and red hue are not as prominent in the video as they are in person. The camera is an old iPhone 4 front facing camera- hence the poor quality.
https://www.youtube.com/watch?v=tRTbC3aDOMo
After nearly two years of work on this fusor, it is at this time that we would like to request admittance into the neutron club. If the above data, videos and descriptions do not meet the requirements of the neutron club, we would be more than happy to collect further data to support our claims in the near future.
Sincerely,
Jack Rosky and Scott Moroch
P.S. We would like to thank everyone here on the fusor.net community as well as those on eBay who kindly donated some of the parts. We would never have been able to accomplish this without the help from all of you. Thank you!