Abstract:
Using data samples collected with the Belle detector at the ϒ(5S) resonance,the e
+e
-→π
+π
-ϒ (
nS) and π
+π
-h
b (
mP) (
n=1,2,3,
m=1,2) processes were investigated. Two charged bottomonium-like states Z
b(10610) and Z
b(10650) were observed in the π
±ϒ(
nS) and π
±h
b (
mP) invariant mass distributions. Since they decay into bottomonium states and are charged, they must have at least four quarks in their composition. Very recently, e
+e
-→π
+π
-π
0 γ ϒ (1S) was also studied, and a search for the X(3872)-like state, X
b , was performed in the bottom sector.