CONFIGURATIONS OF TRIPLETS OF GALAXIES

Three methods of statistical study of triple systems' configurations h ave been proposed. The mathematical expectations of geometrical charac teristics have been compared for observed and simulated triangles in t he first method of configurational parameters. The deviations from tru e configurations due to projection effects have been considered. The o ther two methods employ the division of configurational diagram D into zones. In the inverse-matrix method, the true zonal statistics of con figurations has been restored by solution of the set of linear equatio ns, the right-hand sides of which are the observed numbers of configur ations and the coefficients are the probabilities of zone-to-zone tran sitions due to projections. The method of accidental coincidences comp ares the statictics of observed configurations and projected ones for hypothetical catalogs. If the difference between the number of observe d and projected configurations for each zone does not exceed one and t he total sum of these differences over all zones in not greater than t wo, the hypothetical ensemble has been consiered as <<true>>. For the sample of probably physical triplets of galaxies from the Karachentsev a et al.'s (1979) catalog, the predominance of configurations close to equilateral triangle has been revealed.