A catalog of isolated galaxy pairs limited to absolute magnitude -18.5
  drawn from HyperLEDA database
  The present paper is devoted to the construction of a catalog of isolated
galaxy pairs extracted from the HyperLEDA extragalactic database. The radial
velocities of the galaxies in the pairs are in the range $[3000,16000]$
km.s$^{-1}$. In order to get an unbiased pair catalog as complete as possible,
we have limited the absolute magnitude of the galaxies to $M \leq-18.5$). The
criteria used to define the isolated galaxy pairs are the following: 1)
Velocity criterion: radial velocity difference between the pair members $\Delta
V<500$ km.s$^{-1}$; 2) Interdistance criterion: projected distance between the
members $r_p<1$ Mpc; 3) Reciprocity criterion: each member is the closest
galaxy to the other one, which excludes multiplets; 4) Isolation criterion: we
define a pair as isolated if the ratio $\rho=r_3/r_p$ of the projected distance
of the pair to its closest galaxy (this one having a velocity difference lower
than 500 km.s$^{-1}$ with respect to the pair) and the members projected
interdistance $r_p$ is larger than 2.5. We have searched for these closest
galaxies first in HyperLEDA M-limited source catalog, then in the full one. We
have managed not to suppress the small number of pairs having close-by but
faint dwarf galaxy companions. The galaxy pair catalog lists the value of
$\rho$ for each isolated pair. This method allows the user of the catalog to
select any isolation level (beyond the chosen limit $\rho>2.5$). Our final
catalog contains 13114 galaxy pairs, of which 57\% are fairly isolated with
$\rho>5$, and 30 \% are highly isolated with $\rho \geq 10$.
