b
b
positive parity states
Χ
b0
(2P) - Χ
b0
(1P)
0.373 GeV
Χ
b1
(2P) - Χ
b1
(1P)
0.363 GeV
Χ
b2
(2P) - Χ
b2
(1P)
0.356 GeV
spacing somewhat smaller than 380 MeV
perfectly explained by
meson loops
.