Assisting with hardware R&D for the DRIFT Dark Matter Detection Project

After learning how to use the DipTrace circuit board design program, I was able to assist with three projects which were part of the effort to commission a new DRIFT detector. First, I have produced diagrams for boards that collate wires from the detector into 11 and 12 channels respectively. This proposed grouping scheme will, in theory, allow us to pinpoint where the ionization tracks land on the MWPCs. Second, since the amount of output channels increases dramatically in the 11/12 grouping scheme, I have also began designing a board that can carry multiple preamplifier chips. The commercially available CR-150, which carries the same chip that we use, was utilized as a starting point for design and simplification. As of the time of writing, a two-chip prototype has been manufactured, and its noise level was tested using an oscilloscope. The separation between the two chips was about 0.75 inch. Initial testing indicated no “cross-talk” between the very sensitive chips, thus showing the viability of having more of them on a small circuit board. Further work on the multichip preamp board was delayed due to the more pressing third assignment. The DRIFT collaboration was working within tight time constraints to commission the new detector. Therefore, professor Snowden-Ifft decided to use the existing grouping scheme for the time being (8 groups instead of 11 or 12). Since there were no ready-made grouping boards in Occidental, I manufactured 16 of them, attaching and soldering the necessary connections. The boards themselves functioned normally. However when we stepped up the voltage of the test detector, 4 wires broke from excessive current even though the voltage was (just) within the normal operation range. Modeling of suggests that the system has too much capacitance, which results in more energetic arcing between points with different voltages. Work is underway to correct the problem