Neutrino detector design, attenuation studies, and testing for the νSol project
Abstract
In order to further work on the Sol project funded through a NASA Phase II
NIAC grant, I have performed detailed simulations on the effect of attenuation length on
the performance of the Sol solar neutrino probe using varying energies of electrons and
gamma rays. I have worked to prepare a container to hold our liquid scintillator in order to
perform initial measurements on the ground in order to verify simulation, and have
simulated cosmic ray showers for this comparison. I have also simulated the results of a
triggered gamma ray source incident on the scintillating volume, but there is not test stand
data at this time.
The electron simulations are promising, and suggest that for a .044m vessel, a 0.383
m attenuation length is a sufficient minimum for reading rich signals. The gamma ray
simulations suggest that for the same vessel a 2m attenuation length is a sufficient
minimum. In both cases, decreasing the length of the vessel provides a disproportionately
large shrinking of the minimum attenuation length. Filtering for true and false 0-hit signals
in the gamma sector should bring the minimum attenuation more in line with the
electron’s minimum and allow us to include more dopant in our detector.
I have learned that simple heat sealing is not a feasible solution for a plastic liquid
scintillator container. A much higher pressure industrial environment may solve the
problem, but the project would likely be better suited to injection or blow mold a vessel in
that extreme. I have investigated a glassware solution, but have not yet received pricing
information from the glassmaking company. For the meantime, we have settled on a high
quality plastic glue, though we are not sure this is a feasible long-term solution for the final
space-worthy device.
The initial cosmic ray data matches the simulation data very closely. This result
encourages the continuing project to move onto triggered gamma ray data when possible to
verify the results of that experiment against the simulation.
Description
Thesis (M.S.)-- Wichita State University, College of Liberal Arts and Sciences, Dept. of Mathematics, Statistics, and Physics