DustPedia: A Definitive Study of Cosmic Dust in the Local Universe

Abstract

The European Space Agency has invested heavily in two cornerstones missions;\nHerschel and Planck. The legacy data from these missions provides us with an\nunprecedented opportunity to study cosmic dust in galaxies so that we can\nanswer fundamental questions about, for example: the origin of the chemical\nelements, physical processes in the interstellar medium (ISM), its effect on\nstellar radiation, its relation to star formation and how this relates to the\ncosmic far infrared background. In this paper we describe the DustPedia\nproject, which is enabling us to develop tools and computer models that will\nhelp us relate observed cosmic dust emission to its physical properties\n(chemical composition, size distribution, temperature), to its origins (evolved\nstars, super novae, growth in the ISM) and the processes that destroy it (high\nenergy collisions and shock heated gas). To carry out this research we will\ncombine the Herschel/Planck data with that from other sources of data,\nproviding observations at numerous wavelengths (< 41) across the spectral\nenergy distribution, thus creating the DustPedia database. To maximise our\nspatial resolution and sensitivity to cosmic dust we limit our analysis to 4231\nlocal galaxies (v < 3000 km/s) selected via their near infrared luminosity\n(stellar mass). To help us interpret the data we have developed a new physical\nmodel for dust (THEMIS), a new Bayesian method of fitting and interpreting\nspectral energy distributions (HerBIE) and a state-of-the-art Monte Carlo\nphoton tracing radiative transfer model (SKIRT). In this the first of the\nDustPedia papers we describe the project objectives, data sets used and provide\nan insight into the new scientific methods we plan to implement.\n