The Thuringian State Observatory has been operating a station of the international LOFAR radio telescope since 2010. The whole telescope is currently being upgraded: The computers and software are being renewed. An important milestone has now been reached with the release of version 5.0 of the “LINC” software. Alexander Drabent, a scientist at the Thuringian State Observatory, has played a major role in this success, as he is the main software developer of LINC 5.0.
LINC is the pipeline for the first processing of the data recorded with LOFAR. The LOFAR radio telescope could also be called a software telescope because the alignment of the non-mobile radio antennas is controlled exclusively by software. In addition, the more than 50 LOFAR stations in currently eight countries generate huge amounts of data, which can only be converted into scientific research results using state-of-the-art IT technology and software.
Alexander Drabent explains how LOFAR generates an image of the sky. Photo: TLS
The software and its further development are therefore a relevant component of the telescope itself. “All the knowledge and technology of how the telescope observes is largely contained in the software,” explains Alexander Drabent. As the main software developer for LINC, the scientist supervises and maintains the pipeline.
Pipeline is a key component
The pipeline is a key component for the subsequent processing of the observation data. It is used to compare the recorded data sets from the LOFAR stations with a reference model. This is known as calibration and is a central component of the initial processing. “In order to 'understand' observation data and 'translate' it correctly into an image of the radio sky, for example, we need a reference. The LINC pipeline is responsible for making this possible. Almost all data recorded with LOFAR passes through this pipeline,” explains Drabent.
The pipeline eliminates distortions caused by the telescope itself or by environmental influences so that the observation data produces a clearer signal. LINC also analyzes the quality of the observed data and makes the calibration process transparent. The initial calibration is important. Without it, the observation data cannot be processed further.
LINC has already undergone many development steps. Drabent has been working on it since version 3.0. The new version 5.0 covers a much wider bandwidth of the telescope. For the first time, it can be used for data from both LOFAR antenna arrays, the high-band and low-band antennas. This is a prerequisite for the future operation of LOFAR 2.0: Simultaneous observation with both antenna arrays.
Background: Science with LOFAR
With LOFAR, astronomers can look back billions of years to a time before the first stars and galaxies formed (the so-called “dark ages”). They can map vast areas of the low-frequency radio sky with unprecedented resolution and look for radio transients originating from some of the most energetic explosions in the universe.
This video from ASTRON, the Netherlands Institute for Radio Astronomy, demonstrates how LOFAR works.