Nuclear sizes and ground states
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چکیده
1 Nuclear dimensions 2 Nuclear size may be probed with scattering experiments, such as Rutherford's bombardment of a gold foil with alpha-particles which established the nuclear model of the atom, or electron scattering. Bombarding particles must have de Broglie wavelengths (given by p = h= ̧) smaller than the nuclear size of a few fm to actually probe the nuclear structure; this requires p ̧ 10¡19 kg m s¡1; for electrons the corresponding energy E = (pc +mc) » (10¡21 + 10¡26)1=2 J is about 200 MeV (requires an accelerator), while for alphas it is about 5 MeV (obtainable from natural radioactivity).
منابع مشابه
Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras
In this paper, we generalize the definitions of approximately inner $C_0$-groups and their ground states to the two- parameter case and study necessary and sufficient conditions for a state to be ground state. Also we prove that any approximately inner two- parameter $C_0$--group must have at least one ground state. Finally some applications are given.
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