KINEMATICS OF SUPERNOVA-REMNANTS IN THE SMALL MAGELLANIC CLOUD .1. THE SNRS INSIDE THE NEBULAR COMPLEX N-19, THE SNR-0046-73.5 AND THE SNR-0050-72.8

We present, as a first step in the study of supernova remnants in the Small Magellanic Cloud, the kinematics of the N 19 HII complex and of the supernova remnants SNR 0046-73.5 (N 24) and SNR 0050-72.8 (N 50). The N 19 HII complex shows violent motions compatible with the existen ce of at least three supernova remnants inside it. This agrees with st udies in other wavelengths. The positions and physical properties of t hese remnants (one of them already identified as the SNR 0045-73.4) ar e given. In addition, we present similar studies for the remnants SNR 0046-73.5 and SNR 0050-72.8. While the sample selected in this work is still small, several common features of the studied remnants permit t o establish a kinematical method of identification of supernova remnan ts and shocked nebulae in external galaxies. This method is particular ly useful in the search for supernova remnants inside bright HII regio ns. In all of the cases studied here, the remnants are associated with HII regions. This permits to locate them in depth inside the Small Ma gellanic Cloud. The existence of several remnants inside the complex N 19 of moderate dimensions (diameter = 110 pc) encourages the searchin g for supernova remnants inside HII regions and suggests a revision of the supernova rates in irregular galaxies.