Duoplasmatron Diaries
Duoplasmatron Diaries
Vacuum information
In the spring of 2004 we installed a 30 keV duoplasmatron ion source manufactured by Peabody Scientific.
This ion source is connected to an Einzel lens, gate valve, and scattering chamber
Inside the scattering chamber there are two nested rotatable plates with angle markings for detectors and a liquid-nitrogen cooled target mount. More routinely we use water-cooling for the target mount.
Here are some spectra taken in Summer 2011. This is for a 25-keV deuteron beam on a deuterated polymer target. The refulting fusion reactions - 2H(d,p)3H and 2H(d,n)3He - produce higher energy products:
A persistent problem has been overheating of the target, resulting in melted and damaged targets. We realized that we were accelerating contaminants (oxygen, nitrogen...) in addition to the deuterium beam. This was confirmed by a residual gas analyzer. These contaminants were significant and contributed to the target heating. We designed and built an analyzing magnet using permanent magnets and, in Spring of 2013 magnetically analyzed the beam to remove contaminants.
Time of Flight system. (June 2013)
In summer of 2014 we completed experiments detecting 3He ions in coincidence with neutrons in a plastic scintillator detector. For more, see this.
In the Summer of 2017 we completed a major upgrade, installing an analyzing magnet and a second einzel lens in the system.
The PowerPoint slides describing my sabbatical project, th eLow energy Time-of-Flight Spectrometer" can be found here.