Interferometric Mode

The interferometric imaging mode provides correlated visibility data, just like traditional aperture synthesis radio telescope arrays consisting of antenna elements. The goal of the LOFAR imaging mode is to achieve high fidelity, low noise images of a range of astronomical objects, using customizable observing parameters.

    In this operating mode, station beams are correlated at a central facility (the COBALT correlator) to produce raw visibility data. Further processing, which consists of calibration and imaging, is handled off-line on the central processing cluster, CEP4. Calibration is an iterative process of obtaining the best estimates of instrumental and environmental effects such as electronic station gains and ionospheric delays. The final data products for this mode include the calibrated uv data, optionally averaged in time and frequency, and corresponding image cubes. The visibility averaging reduces the data volume to a manageable level, while minimizing the effects of time and bandwidth smearing.

    In LOFAR Version 2 available in Cycle 15-19, one Low Band Antenna (LBA) and one High Band Antenna (HBA) observing mode with associated "recipes" for the imaging pipeline are offered for allocated observations.

    Expert users can also request modified observing and analysis strategies, which will be considered at the time of the proposal evaluation. This expert mode is not available in cycle 16.

Visit the 'Observing Strategies' and 'Processing and Characterization' sub pages for more details.




Design: Kuenst.    Development: Dripl.    © 2021 ASTRON