Standard-Candle Supernovae are Still Standard, but Why? � Berkeley Lab News Center

Standard-Candle Supernovae are Still Standard, but Why? � Berkeley Lab News Center: ... a new analysis of normal Type Ia supernovae... shows that in fact they have a range of masses. Most are near or slightly below the Chandrasekhar mass, and about one percent somehow manage to exceed it...

A supernova eruption thoroughly trashes its white dwarf progenitor, so the most practical way to tell how much stuff was in the progenitor is by spectrographically “weighing” the leftover debris, the ejected mass...

The SNfactory team compared masses and other factors with light curves: the shape of the graph, whether narrow or wide, that maps how swiftly a supernova achieves its brightest point, how bright it is, and how hastily or languorously it fades away. The typical method of “standardizing” Type Ia supernovae is to compare their light curves and spectra....

“The conventional wisdom holds that the light curve width is determined primarily or exclusively by the nickel-56 mass,” Scalzo says, “whereas our results show that there must also be a deep connection with the ejected mass, or between the ejected mass and the amount of nickel-56 created in a particular supernova.”