The convergence of the hyperspherical expansion for baryons was studied in some detail in Ref. [58]. Table 5.1 shows the result of a calculation with equal masses mi = 1 and the simple power-law potential V = 1 2 ∑ rij0.1, for the ground-state energy and the correlation coefficient δ(3)(r 12). In Table 5.2, we use instead a linear potential V = 1 2 ∑ rij. The convergence is spectacular for the binding energy and slightly slower for the correlation coefficient. Similar conclusions were reached by other authors [55].
For excited states, the convergence pattern is less impressive and, in practice, one has to include more harmonics in the calculation.
Lmax | N | E0 | 103δ(3)(r 12) |
0 | 1 | 1.88075 | 1.128 |
4 | 2 | 1.88032 | 1.186 |
6 | 3 | 1.88020 | 1.221 |
8 | 4 | 1.88019 | 1.232 |
10 | 5 | 1.88018 | 1.239 |
12 | 7 | 1.88018 | 1.245 |
14 | 8 | 1.88017 | 1.248 |
16 | 10 | 1.88017 | 1.249 |
Lmax | En=0 | δ(3)(r 12)n=0 | En=1 | δ(3)(r 12)n=1 |
0 | 3.8647 | 0.05504 | 5.3280 | 0.05505 |
4 | 3.8633 | 0.05628 | 5.3217 | 0.05597 |
6 | 3.8631 | 0.05680 | 5.3208 | 0.05652 |
8 | 3.8631 | 0.05689 | 5.3207 | 0.05664 |