StringFast: Fast Code to Compute CMB Power Spectra induced by Cosmic Strings
Abstract: StringFast implements a method for efficient computation of the C_l spectra induced by a network of strings, which is fast enough to be used in Markov Chain Monte Carlo analyses of future data. This code allows the user to calculate TT, EE, and BB power spectra (scalar [for TT and EE], vector, and tensor modes) for "wiggly" cosmic strings. StringFast uses the output of the public code CMBACT. The properties of the strings are described by four parameters:
- Gμ: dimensionless string tension
- v: rms transverse velocity (as fraction of c)
- α: "wiggliness"
- ξ: comoving correlation length of the string network
Credit: Simon Foreman, Adam Moss, Douglas Scott