A high energy telescope for the Solar Orbiter

A concept for a highly integrated High Energy Telescope with neutron detection capabilities (HETn) is under development. In the current design for implementation on a spinning platform, the instrument consists of one solid-state detector telescope with coincidence electronics. The instrument further includes a CsI scintillator that is read out by photo-diodes. A 30 g plastic scintillator will offer measurement capabilities for low-energy (∼2-100 MeV) solar flare neutrons that are only accessible from an inner heliospheric mission. The scintillators are wrapped in active anti-coincidence shielding. With a total weight of <900 g, the instrument will provide measurements of the time profile, kinetic energy and anisotropy of 4-400 MeV/n protons and heavy ions, and 0.3-15 MeV electrons. This paper will introduce the objectives, the measurement concept, and the critical issues to be addressed by laboratory tests and simulations.