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Purpose | |
We are designing and testing
certain aspects of the Slow Monitoring and Recording system for the Double
Chooz neutrino project, focusing on the system of temperature and magnetic
field sensors which will monitor the status of the final detector. |
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Background | |
Neutrinos |
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Neutrinos are elementary particles that weakly
interact with normal matter and move at nearly the speed of light. Their
properties make them important as a probe into the processes inside of the
Sun or in a nuclear reactor.
Reactor Neutrinos are produced by nuclear beta decay.
An example of b- decay
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Neutrino's Properties | |
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Neutrino Detection 2X | |
A process called inverse beta decay
is used to detect neutrinos.
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Double Chooz |
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Double Chooz is investigating the
value of the q13 neutrino mixing angle. They want to measure this angle
within the range of 0.2 to 0.03-0.02 within three years of data taking. In
order to achieve this scientific goal the detectors need monitoring systems
to ensure 1% or less error in measurements.
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Materials | |
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Projects | |
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Set/Reset Circuit | |
When the magnetic sensors encounter a large magnetic field, the magnetic domains begin to skew, producing inaccurate readings. | |
Diagram for a S/R Circuit
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Set/Reset Pulse
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Prototype PCB for Sensors |
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Prototype Mount for Sensors
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Preliminary Placement of Sensors in the Tank
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PMT Dimensions (Length in mm)
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Results | |
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Oil spectrum data has shown that in the oil exposed to our Teflon coated wire there is a small increase in absorbance around blue because of the printed letters on the insulation. (Graph shown above.) | |
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Temperature sensors covered in thermally conductive epoxy reacts to changes faster than the clear epoxy. The fastest reaction time came with no epoxy at all. (Graph shown above.) | |
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When compared with a pre-calibrated magnetic field sensor, ours was found to be very accurate. (Graph shown above.) | |
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Testing over several days has shown the program can run for an extended period. (Graph shown above.)
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Conclusion Compatibility tests present evidence that the cable, temperature sensor, clear epoxy, and thermally conductive epoxy have little effect on the oil’s absorption spectrum. Testing shows that a greater precision is gained when a set/reset circuit was triggered before with an ADC. |