CONICET | Buscador de Institutos y Recursos Humanos

Context. Studies of interacting galaxies have shown that dwarf galaxies may be produced in the tidal tails during collisions. Numericalsimulations suggest that the total detachment of the tidal dwarf requires the companions mass to be comparable or larger than that of theparent galaxy. This would imply that minor mergers (interaction between unequal mass galaxies) might not form TDGs.Aims. The objectives of the paper is analyse the main properties of a sample of 116 HII regions previously selected from Halpha images of 11minor mergers of galaxies and discuss the nature of these regions comparing their properties with those observed in HII regions in normal andisolated galaxies and TDG candidates.Methods. Individual parameters such as: blue absolute magnitude MB , Halpha luminosity L(Halpha), star formation rate S FR(Halpha) and mass M/Msun ofthese regions were derived and compared with those of the HII regions observed in normal isolated galaxies as well as tidal dwarf candidates.Results. 62% of the HII regions are brighter than MB ≤ −15 mag, which is an upper limit for Giant HII Complexes observed in the spiral armsof Sa and Sb galaxies. Five regions are as bright as the tidal dwarf candidates in the tidal tale of Arp 105. It was also found that 43 regions haveHα luminosities brighter than 10^(40) erg s−1 , which is the upper luminosity limit for HII regions in normal Sc galaxies. The estimated stellarmasses of 32 HII regions are 1×10^(6) < M/Msun < 3 × 10^(7) . These values are comparable to those of young massive clusters (YMC).Conclusions. In our sample we have detected 9 HII regions presenting Halpha luminosities which correspond to star formation rate higher thanthose found in normal HII regions in spiral galaxies. These regions are associated with very massive clusters (1×10^(8) Msun ) typical of TDGs.