In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Q: Hans Hendrik Andersen demonstrated that the stopping power of these objects does not follow the Bethe formula, a result that proved the existence of the Barkas effect, and they are the cause of both pleochroic halos and of mineral metamictization. The last step in the CNO cycle creates a carbon atom and one of these. These are only associated with elements heavier than tellurium. Timothy May discovered that emission of these from DRAM can cause soft errors in microprocessor operations, and the Geiger-Nuttall law relates the life of an isotope to the production of these. For 10 points, identify these particles that escape from radioactive elements via quantum tunneling and Coulomb repulsion, which were used in Rutherford's gold foil experiment and are identical to a helium-4 nucleus.
A:
Science