Shaken, but not expelled: Gentle baryonic feedback from nearby starburst dwarf galaxies
| Autor: | A. Marasco, F. Belfiore, G. Cresci, F. Lelli, G. Venturi, L. K. Hunt, A. Concas, A. Marconi, F. Mannucci, M. Mingozzi, A. F. McLeod, N. Kumari, S. Carniani, L. Vanzi, M. Ginolfi |
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| Přispěvatelé: | Marasco, A., Belfiore, F., Cresci, G., Lelli, F., Venturi, G., Hunt, L. K., Concas, A., Marconi, A., Mannucci, F., Mingozzi, M., Mcleod, A. F., Kumari, N., Carniani, Stefano, Vanzi, L., Ginolfi, M. |
| Rok vydání: | 2023 |
| Předmět: |
ionized-gas outflow
kinematics and dynamic [ISM] starburst [galaxies] jets and outflow [ISM] star-forming galaxie Astronomy and Astrophysics irregular [galaxies] extragalactic distance database dark-matter haloe low-metallicity starburst black-holes dwarf [Galaxies] Settore FIS/05 - Astronomia e Astrofisica Space and Planetary Science |
| Zdroj: | Astronomy & Astrophysics. 670:A92 |
| ISSN: | 1432-0746 0004-6361 |
| Popis: | Baryonic feedback is expected to play a key role in regulating the star formation of low-mass galaxies by producing galaxy-scale winds associated with mass-loading factors of β ∼ 1 − 50. We test this prediction using a sample of 19 nearby systems with stellar masses of 107 M⋆/M⊙ 10, mostly lying above the main sequence of star-forming galaxies. We used MUSE at VLT optical integral field spectroscopy to study the warm ionised gas kinematics of these galaxies via a detailed modelling of their Hα emission line. The ionised gas is characterised by irregular velocity fields, indicating the presence of non-circular motions of a few tens of km s−1 within galaxy discs, but with intrinsic velocity dispersion of 40 − 60 km s−1 that are only marginally larger than those measured in main-sequence galaxies. Galactic winds, defined as gas at velocities larger than the galaxy escape speed, encompass only a few percent of the observed fluxes. Mass outflow rates and loading factors are strongly dependent on M⋆, the star formation rate (SFR), SFR surface density, and specific SFR (sSFR). For M⋆ of 108 M⊙ we find β ≃ 0.02, which is more than two orders of magnitude smaller than the values predicted by theoretical models of galaxy evolution. In our galaxy sample, baryonic feedback stimulates a gentle gas cycle rather than causing a large-scale blow-out. |
| Databáze: | OpenAIRE |
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