English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present photometric and spectroscopic observations of SN 2013aa and SN2017cbv, two nearly identical type Ia supernovae (SNe Ia) in the host galaxyNGC 5643. The optical photometry has been obtained using the same telescope andinstruments used by the Carnegie Supernova Project. This eliminates mostinstrumental systematics and provides light curves in a stable andwell-understood photometric system. Having the same host galaxy also eliminatessystematics due to distance and peculiar velocity, providing an opportunity todirectly test the relative precision of SNe Ia as standard candles. The two SNehave nearly identical decline rates, negligible reddening, and remarkablysimilar spectra and, at a distance of $\sim 20$ Mpc, are ideal as potentialcalibrators for the absolute distance using primary indicators such as Cepheidvariables. We discuss to what extent these two SNe can be considered twins andcompare them with other supernova "siblings" in the literature and their likelyprogenitor scenarios. Using 12 galaxies that hosted 2 or more SNe~Ia, we findthat when using SNe~Ia, and after accounting for all sources of observationalerror, one gets consistency in distance to 3 percent.

SN 2013aa and SN 2017cbv: Two Sibling Type Ia Supernovae in the spiral galaxy NGC 5643