Technical Considerations

We can set as a baseline goal for the observations the acquisition of
a complete data set for 10 galaxies. This would comprise :

1. A set of broad-band images in the visible (U to I) and near infrared (J, H, K) which in certain cases would imply two types of exposures, short for the central zone and long for the external parts of the stellar disc.

2. A complete velocity field in the H(alpha) of the inner part of each galaxy, containing the bar and the circumnuclear zone, plus velocity fields along the spiral arms.

3. A full set of H(alpha) and H(beta) images, which would serve to assist in the interpretation of the broad-band data by estimating dust optical depth, and which would offer a rich of set of HII region statistics for the discs.

4. At least three (major and minor axis and along the bar) long-slit spectra for each object, through the nucleus. For the largest objects these might be supplemented with spectra centered on the ends of the bars. The information obtained combines stellar velocity fields with information on populations, using dwarf-giant discriminators such as the CaII IR triplet, for use in interpreting the broad-band data

We estimate that the total time available should be sufficient to cover this basic goal, given average weather conditions, with a margin of some 15-20%. Observations over and above the baseline would either be directed at obtaining complete information sets for extra galaxies, or for improving data of borderline quality, or for extending the scope of the long-slit observations, both spectrally and spatially.

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