  We investigate the effects of the presence of a non-vanishing net baryon
number density and its diffusion on dilepton production, within a
hydrodynamical description of the medium created at $\sqrt{s_{NN}}=7.7$ GeV
collision energy. This energy value is explored within the Beam Energy Scan
(BES) program at Relativistic Heavy Ion Collider (RHIC) at Brookhaven National
Laboratory. Particular attention is devoted to a new dissipative degree of
freedom: the net baryon number diffusion ($V^\mu$), and to the net baryon
number conductivity ($\kappa$) | a transport coefficients governing the overall
magnitude of $V^\mu$. The effects of $\kappa$ on dilepton production are
assessed, with an outlook on how future experimental dilepton data can be used
to learn more about $\kappa$.
