# PowerLaw¶

class pysm.PowerLaw(map_I, freq_ref_I, map_pl_index, nside, map_Q=None, map_U=None, freq_ref_P=None, unit_I=None, unit_Q=None, unit_U=None, map_dist=None)[source] [edit on github]

Bases: pysm.Model

This is a model for a simple power law synchrotron model.

This function initialzes the power law model of synchrotron emission.

The initialization of this model consists of reading in emission templates from file, reading in spectral parameter maps from file.

Parameters
map_I, map_Q, map_U: pathlib.Path object

Paths to the maps to be used as I, Q, U templates.

unit_*string or Unit

Unit string or Unit object for all input FITS maps, if None, the input file should have a unit defined in the FITS header.

freq_ref_I, freq_ref_P: Quantity or string

Reference frequencies at which the intensity and polarization templates are defined. They should be a astropy Quantity object or a string (e.g. “1500 MHz”) compatible with GHz.

map_pl_index: pathlib.Path object

Path to the map to be used as the power law index.

nside: int

Resolution parameter at which this model is to be calculated.

Methods Summary

 get_emission(self, freqs[, weights]) This function evaluates the component model at a either a single frequency, an array of frequencies, or over a bandpass.

Methods Documentation

get_emission(self, freqs:Unit("GHz"), weights=None)[source] [edit on github]

This function evaluates the component model at a either a single frequency, an array of frequencies, or over a bandpass.

Parameters
freqs: float

Frequency at which the model should be evaluated, assumed to be given in GHz.

Returns
ndarray

Set of maps at the given frequency or frequencies. This will have shape (nfreq, 3, npix).