Medium modification of heavy meson spectra from QCD sum rules

Abstract

Pseudoscalar D meson spectral functions in nuclear medium are analyzed by employing QCD sum rules with the maximum entropy method. This approach enables us to extract the spectral functions without any phenomenological assumption, and thus to visualize modification of the spectral functions due to medium effects from nuclear medium. As a result, it is found that masses of both D+ and D mesons grow gradually with increasing density. Additionally, we construct charge conjugate projected sum rules and observed D+and D- mass splitting of about-20 MeV at nuclear saturation density.