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Context.Following a multi-year minimum of solar activity, a solar energetic particle event on 2020 Nov. 29 was observed by multiple spacecraft covering a wide range of solar longitudes including ACE, the Solar Terrestrial Relations Observatory-A, and the recently launched Parker Solar Probe and Solar Orbiter.Aims.Multi-point observations of a solar particle event, combined with remote-sensing imaging of flaring, shocks, and coronal mass ejections allows for a global picture of the event to be synthesized, and made available to the modeling community to test, constrain, and refine models of particle acceleration and transport according to such parameters as shock geometries and particle mass-to-charge ratios.Methods.Detailed measurements of heavy ion intensities, time dependence, fluences, and spectral slopes provided the required test data for this study.Results.The heavy ion abundances, timing, and spectral forms for this event fall well within the range found in prior surveys at 1 au. The spectra were well fitted by broken power law shapes; the Fe/O ratio was somewhat lower than the average of other events. In addition,3He/4He was very low, with only the upper limits established here.

Context. Silicon solid-state detectors are commonly used for measuring the specific ionization, dE∕dx, in instruments designed for identifying energetic nuclei using the dE∕dx versus total energy technique in space and in the laboratory. The energy threshold and species resolution of the technique strongly depend on the thickness and thickness uniformity of these detectors. Aims. Research has been carried out to develop processes for fabricating detectors that are thinner than 15 μm, that have a thickness uniformity better than 0.2 μm over cm2 areas, and that are rugged enough to survive the acoustic and vibration environments of a spacecraft launch. Methods. Silicon-on-insulator wafers that have a device layer of the desired detector thickness supported by a thick handle layer were used as starting material. Standard processing techniques were used to fabricate detectors on the device layer, and the underlying handle-layer material was etched away leaving a thin, uniform detector surrounded by a thick, supporting frame. Results. Detectors as thin as 12 μm were fabricated in two laboratories and successfully subjected to environmental and performance tests. Two detector designs were used in the High-energy Energetic Particles Instrument, which is part of the Integrated Science Investigation of the Sun instrument suite on NASA’s Parker Solar Probe spacecraft. These detectors have been performing well for more than two years in space. Conclusions. Thin silicon detectors in d E∕dx versus total energy instruments enable the identification of nuclei with energies down to ~1 MeV nuc−1. This research suggests that detectors at least a factor of two thinner should be achievable using this fabrication technique.