Light element depletion in F- and G-type stars

The trio of the rare light elements - lithium, beryllium, and boron - can be destroyed in the interiors of solar-type stars. Lithium is the most susceptible to destruction, followed by Be and then B. The large depletion of Li in the mid-F stars in the Hyades and other clusters is understood to be due to slow-mixing of Li atoms to deep layers where the temperature is high enough to destroy them. New results on the correlation of Li and Be depletions in field F stars support this and argue against diffusion, mass loss, and probably mixing by gravity waves. Rotationally-induced mixing is the most probable cause of the Li and Be depletion. The G stars in the Hyades and other clusters have progressively less Li with decreasing surface temperature, whereas the few Be observations in G dwarfs show little or no depletion. Recent results on B show only small depletions in a few stars, and only in those stars with very large deficiencies in Li and Be.