维基百科，自由的百科全书
氦四，是氦的同位素之一，元素符號為4He。它的原子核由二顆質子和二顆中子所組成。是穩定同位素。其相對豐度是99.999863%
The helium three, is one of helium isotopes, the symbols of the elements is 4He. Its atomic nucleus is composed by two protons and two neutrons. Is the stable isotope. Its abundance is 99.999863%
引用數據:http://ie.lbl.gov/toi/nuclide.asp?iZA=20004
