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تسجيل مستخدم جديدSystematic study of outflows in the Local Universe using CALIFA: I. Sample selection and main properties
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We present a sample of 17 objects from the CALIFA survey where we find initial evidence of galactic winds based on their off-axis ionization properties. We identify the presence of outflows using various optical diagnostic diagrams (e.g., EW(H$alpha$), [Nii]/H$alpha$, [Sii]/H$alpha$, [Oi]/H$alpha$ line-ratio maps). We find that all 17 candidate outflow galaxies lie along the sequence of active star formation in the M$_star$ vs. star-formation rate diagram, without a clear excess in the integrated SFR. The location of galaxies along the star-formation main sequence (SFMS) does not influence strongly the presence or not of outflows. The analysis of the star-formation rate density ($Sigma_{rm SFR}$) reveals that the CALIFA sources present higher values when compared with normal star-forming galaxies. The strength of this relation depends on the calibrator used to estimate the SFR. This excess in $Sigma_{rm SFR}$ is significant within the first effective radius supporting the idea that most outflows are driven by processes in the inner regions of a galaxy. We find that the molecular gas mass density ($Sigma_mathrm{gas}$) is a key parameter that plays an important role in the generation of outflows through its association with the local SFR. The canonical threshold reported for the generation of outflows -- $Sigma_{rm SFR}>0.1$ $mathrm{M}_odot mathrm{yr}^{-1} mathrm{kpc}^{-2}$ -- is only marginally exceeded in our sample. Within the Kennicutt-Schmidt diagram we propose a domain for galaxies hosting starburst-driven outflows defined by $Sigma_{rm SFR}>10^{-2} ,mathrm{M}_odot mathrm{yr}^{-1} mathrm{kpc}^{-2}$ and $Sigma_mathrm{gas}>10^{1.2} , mathrm{M}_odot mathrm{pc}^{-2}$ within a central kiloparcec region.
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