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An experimental campaign was carried out at the NASA Space Radiation Laboratory to perform an additional, independent dosimetric characterization of the beams of protons, helium and carbon ions for radiobiological experiments. The campaign was undertaken by the request and with the support from the National Cancer Institute, U.S. In this initial phase, the goals were to obtain a first assessment of the dosimetric reproducibility of the beam control system, including analysis of spatial homogeneity and evaluation of ion beam contamination. They should facilitate the design of further experimental campaigns for beam characterization for radiobiological experiments. Measurements included reference dosimetry with comparison of in-house and external ionization chambers and electrometers, lateral-dose profile measurements in air, depth-dose profile in a water tank, evaluation of water equivalent thickness of a HDPE binary range shifter and estimation of impurities of the investigated helium-ion beam. The experiments and results are presented.

Free space coupled, InGaAs PIN + TIA Quad Photoreceivers enable multiple space applications that require differential wavefront sensing, such as gravitational wave detectors, and position sensing and tracking, for example inter-satellite optical communication links. Optical crosstalk between the individual quadrants of the 2 × 2 photoreceiver array is a key parameter that limits the position and / or direction sensing error of the system. Therefore, it is imperative to ensure low crosstalk in the quad photoreceivers throughout the mission life.We present 1 mm, 1.5 mm, and 2 mm diameter low noise Quad Photoreceivers that demonstrate crosstalk < -30 dB up to 20 MHz frequency. These devices were subjected to 100 MeV Protons and 100 MeV/n Helium Ions up to a fluence of 1 × 10 10 cm -2 . These tests not only validate the devices for Geostationary Orbit missions, but also for deep space missions outside of Earth's protective magnetosphere where Galactic Cosmic Rays are a significant component of the radiation environment. All devices were found to be fully functional after radiation, and their crosstalk was essentially unchanged in all cases.Pre-and Post-radiation results were also measured for Dark Current vs. Reverse Bias Voltage for the Quad Photodiodes, DC Responsivity of the Quad Photodiodes, Conversion Gain and Bandwidth of the PIN + TIA Quad Photoreceiver, TIA Drive Current, and Input Equivalent Noise Density of PIN + TIA. Although we observed an increase in dark current due to radiation induced displacement damage in the Quad Photodiode, we did not observe any change in any other parameter for Quad Photoreceivers.

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Das System Pd‐Se wird differentialthermoanalytisch, kalorimetrisch, metallographisch und röntgenographisch untersucht.