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HIGH ENERGY PHYSICS SEMINAR TODAY<br class="">
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Monday January 25, 2016<br class="">
ERC 401<br class="">
4:15pm<br class="">
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Speaker: Eric Oberla (UChicago)
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Title:<b class=""> Developing a water Cherenkov optical time-projection chamber </b>
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Abstract: The LAPPD collaboration was formed to develop large-area photodetectors based on micro-channel plates (MCP) for precise time-of-flight measurements in large-scale detectors for high-energy physics. As part of this project, we have designed readout
electronics for these 400 cm^2 photodetectors using a custom front-end 10 gigasample-per-second waveform-digitizing integrated circuit. The prospect of large-area, scalable, and high-granularity photodetectors opens the possibility of building a water-based
`optical time-projection chamber' (OTPC), in which high-energy charged- particle tracks are reconstructed by measuring the relative times and positions of the `drifted' Cherenkov photons.</div>
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<p class="">A first experimental test the OTPC concept was performed at the Fermilab Test-Beam Facility using a 40 kg cylindrical water volume, which was instrumented with an array of small, commercial MCP- PMTs in combination with optical mirrors. The initial
test-beam run examined the detector response to multi-GeV muons. By measuring the time-of-arrival and the position of these photons at the surface of the detector to better than 100 ps and a few mm, we measure a 3D spatial resolution of 15 mm on the particle
track. The application of this technique to larger-scale water-based neutrino detectors will be discussed. </p>
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