Modelling and interpreting observations of forming stars and galaxies

Much of the information that we have about the cold regions where new galaxies, stars and planets are forming comes from analysing the radiation we receive from the dust that is mixed in with the gas. However, the standard procedures for analysing maps of dust continuum emission (garnered by expensive telescopes like SPITZER, HERSCHEL, IRAM and ALMA) only use a tiny fraction of the information available. We have developed a new technique, PPMAP, which increases by a factor between 100 and 1000 the amount of information that can be extracted: the standard procedure delivers just two low-resolution maps, one of the total dust column-density and one of the mean dust temperature, whereas PPMAP delivers maps of the column-densities of dust of different types, and in different temperature intervals, and at greatly improved resolution (typically twelve temperature intervals are used, four different dust types, and pixels twenty times smaller than the standard procedure). This project is aimed at building radiation transport models to interpret this extra information, in terms of the underlying structure of the emitting sources (density and temperature of dust, as a function of position), its environment (the ambient radiation field and the contribution from nearby or embedded stars), and the evolution of dust (for example the coagulation and growth of dust in dense star-forming cores). The resulting diagnostic tools will be applied to star-forming cores, filaments and clouds, as well as external galaxies like M31.
The student will become expert in radiation transport and the underlying microphysics (emission and absorption processes for dust), and the statistical metrics used to compare observed sources with models and simulations.


The start date for this project is 01/10/2018.