Basic Spectrum Generation

The first and most simple way in which TARDIS calculates spectra calculates it directly from the Monte Carlo packets after the final Monte Carlo iteration. This simply requires knowledge of the each packet’s energy and frequency in the lab frame (see Reference Frames) at the end of the iteration. The only other quantity needed is the time duration of the simulation \(\Delta t\), which isc alculated based off of the luminosity of the supernova’s photosphere (see Energy Packet Initialization).

Note

The only packets which are used for this calculation are the packets which escape the outer boundary of the computational domain – those reabsorbed into the photosphere are not included (see Packet Propagation).

The spectrum calculation is very straightforward. A packet of energy \(E_\mathrm{packet}\) contributes a luminosity

\[L_\mathrm{packet} = \frac{E_\mathrm{packet}}{\Delta t}\]

to the spectrum at its frequency.