| Abstract |
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We report on a search in $e^+e^-$ annihilations for new $\pi^0$-like
particles produced in association with a $\tau$-lepton pair. These
objects, with a similar mass and similar decay modes to $\pi^0$ mesons,
could provide an explanation for the non-asymptotic behavior of the
pion-photon transition form factor observed by the Babar
Collaboration. No significant signal is observed, and limits on the
production cross section at the level of 73~fb or 370~fb, depending
on the model parameters, are determined at 90\% confidence level.
These upper limits lie below the cross section values needed to
explain the Babar form factor data.
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