Speaker
Description
Current radio interferometers output multi-petabyte-scale amounts of data per year making the storage, transfer and processing of this data a sizeable challenge. This challenge is expected to persist with the next-generation telescopes such as the Square Kilometre array (SKA) which will be considerably larger in size than current instruments. Lossy compression of interferometric data post-correlation can be used to abate this challenge but any drawbacks from the compression should be well understood in advance.
Lossy data compression reduces the precision of data, introducing additional noise to the data. Since epoch of reionization (EoR) 21 cm studies impose strict precision requirements, the impact of this effect on the 21 cm signal power spectrum statistic is investigated in a bid to either understand or rule out any consequent risk of unwanted systematics.
We establish the scale of the compression noise in the power spectrum, its coherency behaviour and the finally, compare different compression parameters for optimal results. Using observed visibilities datasets as well as simulated ones, we apply visibilities compression and perform a power spectrum analysis on the reference and compressed data. We compare the power spectrum of the compression noise obtained from different compression parameters with the thermal noise and the expected 21 cm signal power.
