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Constraining Type Ia Supernova Delay Time with Spatially Resolved Star Formation Histories

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 نشر من قبل Lifan Wang Prof.
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present the delay time distribution (DTD) estimates of Type Ia supernovae (SNe~Ia) using spatially resolved SN~Ia host galaxy spectra from MUSE and MaNGA. By employing a grouping algorithm based on k-means and earth movers distances (EMD), we separated the host galaxy star formation histories (SFHs) into spatially distinct regions and used maximum likelihood method to constrain the DTD of SNe Ia progenitors. When a power-law model of the form $DTD(t)propto t^{s} (t>tau)$ is used, we found an SN rate decay slope $s=-1.41^{+0.32}_{-0.33}$ and a delay time $tau=120^{+142}_{-83} Myr$ . Moreover, we tested other DTD models such as a broken power law model and a two-component power law model, and found no statistically significant support to these alternative models.



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