supernova light curve

A supernova light curve is the shape of the graph of a changing intensity of light (or other electromagnetic radiation) over the course of a supernova and its aftermath, which is used for analysis to reveal characteristics of the supernova. Different lightcurves from a single supernova can be gathered, based upon different photometry and/or spectrography used when collecting them. Recorded light curves generally begin after the initial brightening since the supernova's beginning cannot be anticipated. The decline-rate of Type Ia supernova light curves have been correlated with their brightness, enabling the use of them as standard candles. Some core collapse supernova light curves include a period of very slow decline (termed its plateau), while at a luminosity which has shown a relation with the supernova's ejecta velocity, the latter of which can be measured through the use of spectrography determining radial velocities, which allows these Type II supernova to be used as standard candles as well. Supernovae lightcurves show evolving spectral signatures indicating particular elements/temperatures, and isotopes. Signatures of radioactive isotopes such as ⁵⁶Ni, ⁵⁶Co (cobalt), ⁶⁰Co, and ⁴⁴Ti (titanium), allow reconstruction of nuclear reactions including radioactive decay, and analyzing backward, reveal information about the explosion and the internal conditions of the progenitor star. Kilonova light curves offer analogous analysis, though only a few have been identified.