THEMIS grids
The [polarised] extinction (EXT[_POL]_xx.RES files) and [polarised] emission (SED[_POL]_xx.RES files) spectra were computed with the DustEM numerical tool using the Mathis et al. (1983) radiation field, scaled by the factor G0 ∈ [0.1, 100]. The spectra are given on a grid containing 800 steps between 0.04 and 105 μm.
The emission files contain the the emission per proton for each grain population 4πνIν/NH in erg/s/H as a function of wavelength (NH is the proton column density).
The extinction files contain the extinction cross-section (σabs+σsca) for each grain population per gram of dust type. The total optical depth and extinction are then (see the DustEM userguide):
τ(λ) = ∑tt (σabstt+σscatt) Mtt/MH mH NH
Aλ = 1.086 × τ(λ).
The size distribution files (SDIST_xx.RES) were also computed with DustEM and contain the mass distribution (a3 dn/dlna in cm3/H) as a function of the effective grain radius a in microns.