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Detection of the self-regulation of star formation in galaxy discs

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 نشر من قبل Javier Zaragoza-Cardiel
 تاريخ النشر 2019
  مجال البحث فيزياء
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Stellar feedback has a notable influence on the formation and evolution of galaxies. However, direct observational evidence is scarce. We have performed stellar population analysis using MUSE optical spectra of the spiral galaxy NGC 628 and find that current maximum star formation in spatially resolved regions is regulated according to the level of star formation in the recent past. We propose a model based on the self-regulator or bathtub models, but for spatially resolved regions of the galaxy. We name it the resolved self-regulator model and show that the predictions of this model are in agreement with the presented observations. We observe star formation self-regulation and estimate the mass-loading factor, $eta=2.5 pm 0.5$, consistent with values predicted by galaxy formation models. The method described here will help provide better constraints on those models.



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