disnht: Modeling X-ray absorption from distributed column densities

Collecting and analysing X-ray photons over either spatial or temporal scales encompassing varying optical depth values requires knowledge about the distribution. In case of sufficiently broad distribution, assuming a single column density value leads to misleading interpretation source emission properties, nominally its spectral model. We present model description for interstellar medium absorption in spectra at moderate energy resolution, extracted regions set independent densities. The (named disnht) approximates distribution with lognormal one is presented table format. solution code are made available can be further generalized tailored arbitrary distributions encompassed by extraction region. disnht expected relevant upcoming large angular scale analyses diffuse emission, such as ones from extended ROentgen Survey an Imaging Telescope Array (eROSITA) future Athena missions.