e
-
+ e
+
→ J/psi + 2 pions
The action of all minima.
The remaining structure is due to the known,
and unknown (for the moment) charmonium vector states.
From left to right, you find:
psi(3770)
,
psi(4040)
,
psi(4160)
, and
psi(4415)
.