Bibcode
Sánchez Almeida, J.; Caon, N.; Muñoz-Tuñón, C.; Filho, M.; Cerviño, M.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 476, Issue 4, p.4765-4781
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6
2018
Citations
25
Refereed citations
22
Description
Using a representative sample of 14 star-forming dwarf galaxies in the
local Universe, we show the existence of a spaxel-to-spaxel
anticorrelation between the index N2 ≡ log ([N II]λ 6583/H
α ) and the H α flux. These two quantities are commonly
employed as proxies for gas-phase metallicity and star formation rate
(SFR), respectively. Thus, the observed N2 to H α relation may
reflect the existence of an anticorrelation between the metallicity of
the gas forming stars and the SFR it induces. Such an anticorrelation is
to be expected if variable external metal-poor gas fuels the
star-formation process. Alternatively, it can result from the
contamination of the star-forming gas by stellar winds and SNe, provided
that intense outflows drive most of the metals out of the star-forming
regions. We also explore the possibility that the observed
anticorrelation is due to variations in the physical conditions of the
emitting gas, other than metallicity. Using alternative methods to
compute metallicity, as well as previous observations of H II regions
and photoionization models, we conclude that this possibility is
unlikely. The radial gradient of metallicity characterizing disc
galaxies does not produce the correlation either.
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Starbursts in Galaxies GEFE
Starsbursts play a key role in the cosmic evolution of galaxies, and thus in the star formation (SF) history of the universe, the production of metals, and the feedback coupling galaxies with the cosmic web. Extreme SF conditions prevail early on during the formation of the first stars and galaxies, therefore, the starburst phenomenon constitutes a
Casiana
Muñoz Tuñón