Research profile E. (Emilio) Ceccotti

E. (Emilio) Ceccotti

Project: Improved modeling of astronomical radio sources with compressive sensing techniques

The 21cm line emitted by neutral hydrogen is one of the most promising probes of the intergalactic medium, and it is particularly important to understand the thermal and ionization history during the Epoch of Reionization. Observing the distribution and evolution in redshift of neutral hydrogen is of fundamental importance to understand the formation and evolution of first structures. The LOw-Frequency ARray (LOFAR) has one of the largest program in the world to achieve this through radio images. However, its large data sets (approximately 5 petabytes) require optimization of imaging algorithms. Furthermore, the Galactic and extragalactic foreground emission is up to 5 orders of magnitudes brighter than the 21cm emission and it has to be subtracted with an accurate sky model. This project will focus on the improvement of imaging algorithms for LOFAR data with compressive sensing techniques, which are ideal to reconstruct the signal from sparse data (such as those collected by radio interferometers) and to generate a physical sky model. These techniques have already been successfully applied in other fields, such as medical imaging and facial recognition, which will benefit from this project. Improving imaging techniques is fundamental to obtain high-fidelity results from the infant Universe.

Keywords: Cosmology, Early Universe, Radio Interferometry, Compressive Sensing Techniques, Sky Modeling.

Fields of expertise involved: Epoch of Reionization, Radio Astronomy, Imaging Algorithms, Signal Processing