Description
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. In order to get an unbiased pair catalog as complete as possible, we have limited the absolute magnitude of the galaxies to M<=-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<500km/s; 2) Interdistance criterion: projected distance between the members r_p_<1Mpc; 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 500km/s 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}>=10.
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