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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present SALT2X, an extension of the SALT2 model for SN Ia supernova lightcurves. SALT2X separates the light-curve-shape parameter x1 into an x1r and x1ffor the rise and fall portions of the light curve. Using the Joint LightcurveAnalysis (JLA) SN sample, we assess the importance of the rising and fallingportions of the light curve for cosmological standardization using a modifiedversion of the Unified Nonlinear Inference for Type Ia cosmologY (UNITY)framework. We find strong evidence that x1r has a stronger correlation withpeak magnitude than x1f. We see evidence that standardizing on the rise affectsthe color standardization relation, and reduces the size of the host-galaxystandardization and the unexplained ("intrinsic") luminosity dispersion. SinceSNe Ia generally rise more quickly than they decline, a faster observingcadence in future surveys will be necessary to maximize the gain from thiswork, and to continue to explore the impacts of decoupling the rising andfalling portions of SN Ia light curves.

SN Ia Standardization on the Rise: Evidence for the Cosmological Importance of Pre-Maximum Measurements