³He,^20,21,22Ne,¹⁴C,¹⁰Be,²⁶Al, and³⁶Cl in magnetic fractions of cosmic dust from Greenland and Antarctica

We report on studies of the concentrations of cosmogenic nuclides in the magnetic fraction of cosmic dust particles recovered from the South Pole Water Well (SPWW) and from Greenland. Our results confirm that cosmic dust material from these locations contains measurable amounts of cosmogenic nuclides. The Antarctic particles (and possibly those from Greenland as well) also contain minor amounts of solar Ne. Concentrations of cosmogenic nuclides are consistent with irradiation of this material as small objects in space, with exposure ages similar to the expected Poynting-Robertson (P-R) lifetimes of 50-200 kyr for particles 25-100 mu m in size.