Approximately 2000 nuclides remain to be discovered between the proton and neutron driplines in Figure 11-15b. Consider those that lie on the energy parabola (see Figure 11-22a) for A = 151, whose only stable isotope is ¹⁵¹Eu.

(a) From the data in Appendix A, draw an accurate diagram of the A = 151 parabola showing known nuclides and those yet to be discovered between Z = 50 and Z = 71.

(b) Determine where the edges of the driplines lie for A = 151, that is, the lowest mass isotopes for which spontaneous proton or neutron emission becomes possible.

Figure 11-15b

Figure 11-22a

(b) Proton number 82 50 28 20 CON 8 2 Proton dripline 28 20 28 50 peoploits 82 promieniow Neutron dripline Neutron number 126