We study the difference between
E(4260) and the data for π+π- J/ψ



We compare the difference to
D*D* open-charm-pair production.

data from BaBar
Phys. Rev. Lett. 95, 142001 (2005)
and Phys. Rev. D79, 092001 (2009)
figure from arXiv:1005.1010