Speaker
Dr
ALBERTO MARTINEZ TORRES
(IF-UNIVERSIDADE DE SAO PAULO)
Description
In this paper we study the reaction $e^+ e^- \to (D^* \bar D^*)^{\pm} \pi^{\mp}$ in which the BESIII collaboration has claimed the existence
of a $1^+$ resonance, named $Z_c(4025)$, in the $D^*\bar D^*$ invariant mass spectrum with a mass around 4026 MeV and width close to 26 MeV . We determine the $D^*\bar D^*$ invariant mass distribution
and find that although the explanation considered by the BESIII
collaboration is plausible, there are others which are equally
possible, like a $2^+$ resonance or a bound state. Even more, we find
that the data can be explained without the existence of a
resonance/bound state. In view of the different possible
interpretations found for the BESIII data, we try to devise a strategy which could help in identifying the origin of the signal reported by
the BESIII collaboration. For this, we study the dependence of the
$D^*\bar D^*$ spectrum considering the different options as a function of the total center of mass energy. We arrive to the conclusion that
increasing the center of mass energy from 4.26 GeV to 4.6 GeV can be useful to distinguish between a resonance, a bound state or just a
pure background as being responsible for the signal found. This information should be useful for future experiments.
Primary author
Dr
ALBERTO MARTINEZ TORRES
(IF-UNIVERSIDADE DE SAO PAULO)
