The influence of interactions and minor mergers on the structure of galactic disks - I. Observations and disk models

This paper is the first part in our series on the influence of tidal intera ctions and minor mergers on the radial and vertical disk structure of spira l galaxies. We report on the sample selection, our observations; and data r eduction. Surface photometry of the optical and near infrared data of a sam ple of 110 highly-inclined/edge-on disk galaxies are presented. This sample consists of two subsamples of 61 non-interacting galaxies (control sample) and of 49 interacting galaxies/minor merging candidates. Additionally, 41 of these galaxies were observed in the near infrared. We show that the dist ribution of morphological types of both subsamples is almost indistinguisha ble, covering the range between 0 less than or equal to T less than or equa l to 9. An improved, 3-dimensional disk modelling- and fitting procedure is described in order to analyze and to compare the disk structure of our sam ple galaxies by using characteristic parameters. We find that the vertical brightness profiles of galactic disks respond very sensitive even to small deviations from the perfect edge-on orientation. Hence, projection effects of slightly inclined disks may cause substantial changes in the value of th e disk scale height and must therefore be considered in the subsequent stud y.