Extended Data Fig. 5: Joint confidence level contours of the parameters inferred from the MCMC-based fitting.
The demonstrated parameters are the time of the first light t0 (in a unit of days after MJD 60,000.0), the radius of the progenitor star Rstar (in a unit of solar radius), and the r-band optical depth of the circumstellar dust measured at t0. Best-fit parameters are marked by horizontal and vertical lines and labeled with their 1σ confidence levels. The inner, middle, and outer contours centered at any intersection of parameter pairs show the 68%, 95%, and 99.7% confidence levels, respectively. The likelihood histograms are scaled to 1 for all the three parameters.
