hpmoc.psf module

Functions for working with point sources, applying point spread functions (PSFs) thereto, and making those PSFs compatible with other HEALPix skymaps.

hpmoc.psf.psf_gaussian(ra, dec, σ, cutoff=5, pt_label=None, nside=None, nside_factor=1, **kwargs)

Create a new Gaussian point-spread-function (PSF) PartialUniqSkymap from the right-ascension ra, declination dec, and standard deviation σ of a point-source. ra, dec, σ can be angular astropy.units.Quantity instances (radians or degrees) or scalar values in degrees.

Parameters

  • ra (float or astropy.units.Quantity) – Right Ascension of the center of the distribution.

  • dec (float or astropy.units.Quantity) – Declination of the center of the distribution.

  • σ (float or astropy.units.Quantity) – Standard deviation of the distribution.

  • cutoff (float, optional) – How large of a disk to query in multiples of σ, i.e. the support of the PSF in units of σ.

  • pt_label (str, optional) – A string label for this point when plotting (e.g. the event ID).

  • nside (int, optional) – NSIDE to use. If not specified, calculated automatically using nside_factor.

  • nside_factor (float, optional) – If nside is not provided, calculate the NSIDE value giving pixel widths smaller than σ * nside_factor. In other words, set the resolution in units of σ.

  • **kwargs – Keyword arguments to pass to PointsTuple.