“The entire dataset could be processed on Spider, the high-performance data processing platform hosted at SURF in the Netherlands, in just a few months,” said Jurjen de Jong, a postdoctoral researcher at Leiden Observatory and ASTRON who led the research.
An international team led by researchers from Leiden University produced the deepest view of low-frequency radio galaxies in the Universe. Using the LOw Frequency ARray, the team observed ELAIS-N1, a region of the northern sky containing very little galactic dust, gas, or stars.
Deep Sky Observations With LOFAR
Astronomers at the LOFAR observatory have spent years observing ELAIS-N1 to map low-frequency radio sources. The latest image has twenty times the resolution of the previous LOFAR image, achieved through modern interferometry combining light from multiple telescopes.
The full image features 63,000 radio sources, including quasars and star-forming galaxies. This new view emerged from 200 hours of observation, amounting to 400 terabytes of data in an 8-billion-pixel image.
Data Processing on the Spider Platform
Processing this amount of data at high resolution was impossible a few years ago. Researchers from the Netherlands Institute for Radio Astronomy and their collaborators developed the Spider data-processing platform, reducing processing times by a factor of ten alongside other calibration improvements.
LOFAR’s high sensitivity revealed numerous filaments surrounding radio galaxies near galaxy clusters, resolving structures that required combining high-resolution and low-frequency observations.
Active Galactic Nuclei and Star-Forming Galaxies Dominate the Image
Active Galactic Nuclei dominate the image as bright centers of galaxies powered by supermassive black holes and their accretion disks. These quasars produce relativistic jets of superheated gas and dust emanating from polar regions and emitting considerable radiation.
The high-resolution data let scientists discern individual radio sources and massive jets instead of featureless blobs. Small, young galaxies experiencing high rates of star formation make up the other major population captured in the survey.
LOFAR2.0 Upgrades Enable Wider Higher-Resolution Images
This work demonstrates the potential of the upgraded LOFAR2.0 telescope currently developed by ASTRON and European partners. These upgrades will enable wider, higher-resolution images to keep LOFAR competitive with next-generation radio telescopes like the Square Kilometer Array.
The data will be combined with optical, infrared, and X-ray observations from other telescopes to determine properties like the distance and mass of each radio source.
Frequently Asked Questions About the LOFAR Survey
What telescope was used to create the new image?
Researchers used the LOw Frequency ARray to observe the ELAIS-N1 region of the northern sky.
How much data does the new image contain?
The final product amounts to 400 terabytes of data compiled into an 8-billion-pixel image.
Where was the data processed?
The dataset was processed on the Spider high-performance data processing platform hosted at SURF in the Netherlands.