Aβ-Decay Energy Systematics

Abstract

A /3-decay energy systematics is presented which exhibits linear relations for disintegration energies between atoms (Z,N) and (Z-f-1, TV-1) when plotted as a function of N keeping Z constant. Separate plots are necessary for odd and even values of A. The disintegration energy lines show marked discontinuities for N=50, 82, and 126. There is also considerable indication of a discontinuity at TV=28, and in the region of iV=20 sharp changes in slope are observed. Proton magic numbers at 50, 82, and possibly 28 are indicated by gaps in the spacing of the disintegration energy lines. No definite submagic numbers are at present identifiable. Changes in the even-odd differences of neutron and proton binding energies show up as changes in the line separation pattern. The most striking pattern changes can be interpreted as due to decreases in the even-odd differences for both neutrons and protons after their respective magic numbers. The systematics is useful in estimating disintegration energies in cases where measurements have not yet been made. Part of a systematics for double fi decay is also shown.

ExperimentalQ ?-values of several short-lived nuclides with mass number 85?A?103

“…A standard way to present the systematics of Q~-values is the Way-Wood diagram [15], where the decay energies are plotted as a function of the mass number A (or neutron number N). For constant values of N or Z, Qa is a smooth, almost linear function of A except at main shell closures where a sudden rise in the decay energy occurs.…”

Decay Properties ofI136

“…7 we have shown a comparison of the I-Xe mass differences in the manner used by Way and Wood. 13 Here the mass difference of the isobaric pairs 8 -°i * "i * 1 ' « 1 ' 1 ' 1 ' » • 1 • r » I …”

Yields of Fission-Recoil Bromine by Delayed-Neutron Studies

“…(15,30,31). Qjj and Bn can be estimated for the other nuclides from beta-dec9.7 systematics (32,33) or neutron binding-energy systematics (34,35,36).…”