Oswald H. W. Siegmund

TL;DR: In this article, the performance of opaque Galium Nitride (GaN) photocathodes deposited directly on novel Microchannel Plates (MCPs) was investigated and the design of currently processed sealed tube event counting detector with an opaque GaN photocathode was also described.

TL;DR: In this article, a hybrid imaging detector is described for the next generation adaptive optics (AO) wavefront sensors, which consists of proximity focused microchannel plates (MCPs) read out by pixelated CMOS application specific integrated circuit (ASIC) chips developed at CERN.

TL;DR: In this paper, a hybrid optical detector is described that has many of the attributes desired for the next generation AO wavefront sensors, including zero readout noise (photon counting) and can be read out at 1kHz frame rates.

Abstract: We present our latest results in the development of Silicon micromachined microchannel plates, which open completely newpossibilities in the detector technologies. For the first time Z-stacks of Si microchannel plates with pore bias of 5-8 degreeswere tested in a high gain photon counting imaging detector without any post-amplification stage with conventional glassMCP's. The gain of Z-stacks of Si (40:1 L/D, 6 µm pores on 8 µm centers, 18-25 mm in diameter) MCP's was found to be ashigh as ~10 6 with peaked pulse height distribution. The full-field illumination images appeared to be quite uniform, withrelatively small (~±10%) gain variation. Quantum efficiency of opaque diamond photocathode deposited on Si MCP wasmeasured in reflection mode and compared with the performance of flat-substrate diamond photocathodes. We also presentthe results of our study of long-term gain stability of Si MCP's: variation of Si MCP gain as a function of extracted chargewas investigated.

TL;DR: The Rosetta/ALICE instrument as discussed by the authors is a low-power (4 W) low-cost imaging spectrometer optimized for cometary ultraviolet spectroscopy, which is used to characterize the cometary nucleus, coma and nucleus/coma coupling of the Rosetta mission prime target comet 46P/Wirtanen.