Astrophysics Source Code Library

Making codes discoverable since 1999


A list of keywords associated with codes in the ASCL.

NASA (134), Kepler (28), Spitzer (13), TESS (8), Fermi (6), HITS (5), HST (5), ROSAT (4), CGRO (3), RXTE (3), Swift (3), ASCA (2), Chandra (2), COBE (2), Geotail (2), Heliophysics (2), Herschel (2), LRO (2), Magellan (2), MRO (2), NICER (2), Polar (2), Rosetta (2), Wind (2), WISE (2), WMAP (2), Apollo (1), Cassini (1), Dawn (1), GOES (1), Hinode (1), Hitomi (1), InSight (1), INTEGRAL (1), ISO (1), Juno (1), JWST (1), Lucy (1), Lunar Quest (1), MAVEN (1), MESSENGER (1), MGS (1), NEAR (1), New Horizons (1), NISAR (1), NuSTAR (1), OSIRIS-REx (1), Parker Solar Probe (1), Psyche (1), RHESSI (1), SOFIA (1), SOHO (1), STEREO (1), Suzaku (1), THEMIS (1), TRMM (1)

Codes associated with 'ISO'

[ascl:1102.022] PDRT: Photo Dissociation Region Toolbox

Ultraviolet photons from O and B stars strongly influence the structure and emission spectra of the interstellar medium. The UV photons energetic enough to ionize hydrogen (hν > 13.6 eV) will create the H II region around the star, but lower energy UV photons escape. These far-UV photons (6 eV < hν < 13.6 eV) are still energetic enough to photodissociate molecules and to ionize low ionization-potential atoms such as carbon, silicon, and sulfur. They thus create a photodissociation region (PDR) just outside the H II region. In aggregate, these PDRs dominate the heating and cooling of the neutral interstellar medium.

The PDR Toolbox is a science-enabling Python package for the community, designed to help astronomers determine the physical parameters of photodissociation regions from observations. Typical observations of both Galactic and extragalactic PDRs come from ground- and space-based millimeter, submillimeter, and far-infrared telescopes such as ALMA, SOFIA, JWST, Spitzer, and Herschel. Given a set of observations of spectral line or continuum intensities, PDR Toolbox can compute best-fit FUV incident intensity and cloud density based on our models of PDR emission.