Accelerating dust temperature calculations with graphics-processing units

When calculating the infrared spectral energy distributions (SEDs) of galaxies in radiation-transfer models, the calcu-lation of dust grain temperatures is generally the most time-consuming part of the calculation. Because of its highly parallel nature, this calculation is perfectly suited for massively parallel general-purpose Graphics Processing Units (GPUs). This paper presents an implementation of the calculation of dust grain equilibrium temperatures on GPUs in the Monte-Carlo radiation transfer code sunrise, using the CUDA API. The GPU can perform this calculation 69 times faster than the 8 CPU cores, showing great potential for accelerating calculations of galaxy SEDs. Key words: dust, radiative transfer, methods: numerica