Radioactive Planet Formation

Young stellar objects are observed to have large X-ray fluxes and thought produce commensurate luminosities in energetic particles (cosmic rays). This particle radiation, turn, can synthesize short-lived radioactive nuclei through spallation. With a focus on 26Al, this paper estimates the expected abundances of produced by spallation during epoch planet formation. In model, cosmic rays accelerated near inner truncation radii circumstellar disks, rX ? 0.1 au, where intense magnetic activity takes place. For planets forming region, be enhanced over values inferred for early solar system (from meteoritic measurements) factors ?10?20. These influence process formation properties several ways. The minimum size required planetesimals become fully molten decreases with increasing levels enrichment, such melting leads loss volatile components, including water. Planets an inventory significant internal luminosity, which comparable that provided host star; additional heating affects both atmospheric mass chemical composition. Finally, habitable zone red dwarf stars is coincident reconnection so at those locations will experience maximum exposure radiation subsequent depletion volatiles.