Decays of the rho mesons--a neglected source of low-mass dileptons?

The production of dileptons is considered an important tool in the diagnosis of strongly interacting matter created in ultra-relativistic heavy-ion collisions. Some experiments observed an excess of the low-mass dileptons over the expectation represented by the ``cocktail'' composed of the contributions from decays of the free-streaming hadrons leaving the interaction region. We show that at least a part of the effect may be caused by underestimating the rho-meson component in the ``cocktail.''