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Projeto Observacional para 2016A - SO2016A-008

Autor: Claudia Mendes de Oliveira
Instituição: IAG
e-mail: oliveira@astro.iag.usp.br

Jonathan Hernandez Fernandez

Título: Star-Forming Compact Groups: A complete redhisft survey

Resumo: We have recently identified a local sample (z<0.15) of 280 Star-Forming Compact Groups (SFCGs) of galaxies in the ultraviolet Galaxy Evolution EXplorer (GALEX) All-sky Imaging Survey (AIS). The SFCG sample presents a combination of properties different from the group samples studied up to now, such as low velocity dispersions ~120 km/s, small dynamical time-scales ~0.7 Gyr and a high star-forming fraction ~95%. This points to the SFCGs being in an evolutionary stage distinct from those groups selected in the optical and near-infrared wavelenghts. More than 57% of SFCG UV galaxies have not known redshifts. A complete compilation of redshifts for the UV-bright and also for the optically-bright group member candidates of SFCGs is mandatory to confirm that those groups without a signficant number of known redshifts, are velocity concordant and also for accurately derive group properties such as velocity dispersion, dynamical time-scales, total group luminosity and mass-to-light ratios.