Difference of R0 between protons and neutrons

Last modification: 1996/3/21
A figure ( GIF file of 4.7KB or PS file of 34KB ) presents a comparison of the values of R0 between protons and neutrons for the ground-states of the 1029 even-even nuclei (denoted by plus symbols) and the first-excited solution of 758 even-even nuclei for HF+BCS with SIII force. The r.m.s. difference is 0.18 fm, while the largest differences occur in the nuclei indicated by letters from A to F. We tabulate these nuclei below: 
Symbol  Nucleus    R0neu     R0pro
A       22S        3.3 fm   4.6 fm
B       20Si       3.3      4.2    (excited state)
C       16Be       3.9      3.0  
D        8C        2.5      3.4  
E       22C        4.2      3.3  
F       14Be       3.8      2.9
Among the nuclei mentioned above, 22S, 20Si, and 8C are outside the proton drip line. Hence the maximum difference for nuclei in the ground state inside the drip lines occurs in 16Be.

Incidentally, when we plotted the r.m.s. radii rrms instead of R0, we found that the resulting graph looked quite similar to the figure except for a scaling relation R0 ~ (5/3)1/2 rrms.