Poster Abstract

P10.53 Marc Pound (University of Maryland)

Theme: Data processing pipelines

The PhotoDissociation Region Toolbox: Past and Future

Twenty years ago, we launched the PhotoDissociation Region Toolbox (PDRT) as part of our Web Infrared ToolShed (WITS). In this poster, we review where PDRT has been and where it is going.

PDRT, based on the PDR models of Wolfire et al.(1990) and Kaufman et al. (1999, 2006), is designed to help astronomers determine the physical parameters of photodissociation regions from observations. Users enter the flux and errors of their lines or continuum and PDRT does a fit to find the best interstellar FUV radiation field G0 and hydrogen number density n.

Despite lack of continuous funding we have kept PDRT going because we view it as an important science-enabling tool for the community (as evidenced by the many papers published using PDRT products). Over the years, we increased the number of spectral lines covered to keep up with new telescopes and missions, added low metallicity models, and shepherded it through multiple computer replacements and operating system upgrades.

Recently we were awarded funding to make significant improvements both in the models PDRT presents and the underlying software infrastructure. Our PDR code has already been upgraded to provide more accurate physics and chemistry, including molecular freeze-out, updated collision and chemical rates, and new chemical pathways, in particular for oxygen chemistry.

We will deploy updated models that include all these improvements and allow future updates to be easily implemented so that users always get the best current model. We will also rewrite the underlying web code from scratch using modern design principles and give users more control through Python notebooks.