Nanosecond Sampling of the Radio Sky with I-LOFAR's Transient Buffer Boards (TBB)

The LOw Frequency ARray (LOFAR) is an interferometeric array that operates at 10-240 MHz, with a central hub in the Netherlands and 13 international stations across Europe [1]. LOFAR’s Transient Buffer Boards (TBBs) allow upwards of 5 s of data to be recorded at a temporal resolution of ~5.12 ns. Here, we described the development of a data acquisition system to capture TBB observations of solar variability from the Irish LOFAR station (I-LOFAR) at Birr Castle in the Irish Midlands. The system consists of a head node controlling 4 processing nodes offering 64 GB of RAM, as well as an initial 48 TB RAID6 storage node.

We present first-light TBB time series data, along with all-sky observations data from a subset of I-LOFAR’s Low Band Antennas (LBAs). We also discuss the development of a software based beamformer for TBB data with plans to observe the sun with dynamic spectra using nanosecond time resolution. This could give a new insight into rapidly varying phenomena in the solar atmosphere.