The sherpa.astro module

Physical constants for astronomical spectra

This module contains some physical constants needed to perform conversions that are common in the sherpa.astro module, e.g. from energy to wavelength.

Constants

charge_e	elementary charge from nist.gov in units appropriate for converting between keV and erg.
hc	The product of Planck constant (h) and speed of light (c) using values from nist.gov in units appropriate for converting between keV and Angstroms.