FIR SEDs from dusty Radiative transfer simulations

With Chris Hayward, Henry Ferguson and Rachel Somerville, we analyzed the FIR SEDs of a set of hydro-dynamically simulated galaxies representative of both local and high redshift universe. We find that infrared luminosity and dust mass together are the main driver for the shape of the FIR SEDs. This can potentially solve the long standing problem of sub-mm number counts where current SAMs largely underpredict.

This Figure shows the compilation of the SEDs

from SUNRISE in a plane of IR luminosity and Dust mass. At fixed dust mass, SEDs become hotter with

increasing LIR. At fixed LIR, SEDs become cooler

with increasing the dust mass. This is the consequnece of thermal equilibrium of dust with the

radiation field.

 

Confusion noise

High number density of the sources and large beams of FIR telescopes, leads to confusion noiseWe introduce a novel method to overcome confusion noise by using Bayesian priors on the flux of the emitting sources and strong priors on their positions from HST observations.

This Figure shows how many sources in a tiny patch of a simulated PACS160 Herschel image are connected

together, meaning they influence each other's photometry. Our method finds the blended groups and fits the pixels around them separately from the rest of the imege (the blue contour)