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  • VALES
    Couto, Guilherme S.; Hughes, Thomas M.; Boquien, Médéric; Ibar, Eduardo; Viaene, Sébastien; Leiton, Roger; Xue, Yongquan

    Astronomy and astrophysics (Berlin), 10/2021, Letnik: 654
    Journal Article

    We characterize the ionized gas outflows in 15 low-redshift star-forming galaxies, a Valparaíso ALMA/APEX Line Emission Survey (VALES) subsample, using MUSE integral field spectroscopy and GAMA photometric broadband data. We measure the emission-line spectra by fitting a double-component profile, with the second and broader component related to the outflowing gas. This interpretation is in agreement with the correlation between the observed star-formation rate (SFR) surface density (Σ SFR ) and the second-component velocity dispersion ( σ 2nd ), expected when tracing the feedback component. By modeling the broadband spectra with spectral energy distribution fitting and obtaining the star-formation histories of the sample, we observe a small decrease in SFR between 100 and 10 Myr in galaxies when the outflow H α luminosity contribution is increased, indicating that the feedback somewhat inhibits the star formation within these timescales. The observed emission-line ratios are best reproduced by photoionization models when compared to shock ionization, indicating that radiation from the young stellar population is dominant and seems to be a consequence of a continuous star-formation activity instead of a “bursty” event. The outflow properties, such as the mass outflow rate (∼0.1  M ⊙ yr −1 ), the outflow kinetic power (∼5.2 × 10 −4 % L bol ), and the mass loading factor (∼0.12), point toward a scenario where the measured feedback is not strong and has a low impact on the evolution of galaxies in general.