An estimate of the mass from quarkonium spectra.

Abstract

Using a string inspired theory and assuming that the dilaton is dark matter candidate, we determine the mass of the dilaton from the heavy quarkonium spectra with Dick potential. This potential has a remarkable property of leading to a confining phase parameterized by the non zero mass for the dilaton and a mass scale f. By phenomenological investigation of Dick potential it is shown that the energy levels of charmonium, bottommonium and the B c fit well the experimental data when the dilaton mass is given a value about 57MeV . This estimate lies in the range of values predicted for the dilaton as a cold dark matter, and support the recent experimental evidence for light (1-100 MeV) dark matter as a possible explanation of 511keV gamma-ray emission.