  The analysis of exoplanetary atmospheres by means of high-resolution
spectroscopy is an expanding research field which provides information on
chemical composition, thermal structure, atmospheric dynamics and orbital
velocity of exoplanets. In this work, we aim at the detection of the light
reflected by the exoplanet 51~Peg~b employing optical high-resolution
spectroscopy. To detect the light reflected by the planetary dayside we use
optical HARPS and HARPS-N spectra taken near the superior conjunction of the
planet, when the flux contrast between the planet and the star is maximum. To
search for the weak planetary signal, we cross-correlate the observed spectra
with a high S/N stellar spectrum. We homogeneously analyze the available
datasets and derive a $10^{-5}$ upper limit on the planet-to-star flux contrast
in the optical. The upper limit on the planet-to-star flux contrast of
$10^{-5}$ translates into a low albedo of the planetary atmosphere ($\rm
A_g\lesssim0.05-0.15$ for an assumed planetary radius in the range $\rm
1.5-0.9~R_{Jup}$, as estimated from the planet's mass).
