单词 | helion |
释义 | helionn. Nuclear Physics. (a) The nucleus of the normal helium isotope (4He), consisting of two protons and two neutrons; an alpha-particle. (b) The nucleus of the helium isotope 3He, consisting of two protons and one neutron. ΘΚΠ the world > matter > physics > atomic nucleus > radioactive isotope > specific isotopes > [noun] > nucleus of helium isotope helion1930 1930 Sci. Abstr. A. 33 969 Equilibrium tends to be conserved between the number of helions (helium nuclei) in the nucleus and the number of free nuclear electrons. 1964 L. Pauling in Nature 4 Jan. 61/1 I suggest that the word helion be used for the α-particle, the nucleus of the helium atom. 1965 New Scientist 14 Oct. 87/2 The helium nucleus, or helion, consisting of two neutrons and two protons. 1972 Nature 8 Dec. 325/1 In the case of deuterons, the low binding energy makes it easy to calculate the deuteron-nucleus potential from the constituent neutron-nucleus and proton-nucleus optical potentials, but for the more tightly bound helions, tritons and α particles this cannot yet be done with sufficient accuracy. This entry has not yet been fully updated (first published 1976; most recently modified version published online March 2019). < n.1930 |
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