  We investigate light dark matter production associated with a heavy
quarkonium at B factories in a model-independent way by adopting the effective
field theory approach for the interaction of dark matter with standard model
particles. We consider the effective operators for the dark matter-heavy quark
interaction, which are relevant to the production of dark matter associated
with a heavy quarkonium. We calculate the cross sections for dark matter
production associated with a J/psi or eta_c to compare with the standard model
backgrounds. We set bounds on the energy scale of new physics for various
effective operators and also obtain the corresponding limits for the dark
matter-nucleon scattering cross sections for light dark matter with mass of the
order of a few GeV.
