Unlocking the LOFAR LTA

In this paper we discuss our efforts in "unlocking" the Long Term Archive (LTA) of the LOFAR radio telescope. This is a large (> 43 PB) archive that expands with about 7 PB per year by the ingestion of new observations. It consists of coarsely calibrated "visibilities", i.e. correlations between signals from LOFAR stations. Currently, only a small fraction of the LOFAR LTA consists of sky maps, which are needed for most astronomical research. Unfortunately, creating such sky maps can be challenging, due to the data sizes of the observations and the complexity and compute requirements of the software involved. We try to fix this by enabling a simple one-click-reduction of LOFAR observations into sky maps for any user of this archive. This work was performed as part of the PROCESS 1 project, which aims to provide generalizable open source solutions for user friendly exascale data processing.