Extended Data Fig. 4: Color-based age constraints for AT 2016jka.
From: A gravitationally lensed supernova with an observable two-decade time delay
Constraints are shown separately for Image SN1 (panels a and b), image 2 (c and d), and image 3 (e and f), using the methodology described in Methods: Color Curve Age Constraints. Large lower panels (b, d and f) show the observations and model fits. Each magenta shaded region shows the 1σ range of the measured F105W-F160W color, which corresponds to a U-V color in the rest-frame. The model fits are shown as grey shaded regions, indicating the 68% confidence interval of the best-fit SALT2 color curve, with the median model shown as a solid line. The small upper panels (a, c and e) show the posterior for the age of each image from SNTD, using a prior on the SALT2 color parameter (c) based on known population characteristics of SNIa. The effect of adding this prior is slight, with no significant deviation from the best-fit value of \(c = 0.02_{-0.05}^{+0.04}\).
