Assertion: atom's particle | /r/HasProperty | helium nuclei
Facets:
Source sentences:
text: This requires a nearly simultaneous collision of three alpha particles (helium nuclei), as the products of further nuclear fusion reactions of helium with hydrogen or another helium nucleus produce lithium-5 and beryllium-8 respectively, both of which are highly unstable and decay almost instantly back into smaller nuclei.
text: Rutherford observed that when a beam of alpha particles (which are now known to be helium nuclei) struck a thin gold foil, some of the particles were deflected backward.