LOFAR 58MHz Legacy Survey of 3CRR catalog

The Low Frequency Array (LOFAR) is uniquely able to perform deep, high- resolution imaging at frequencies below 100MHz. Observations in this regime, using the Low Band Antenna (LBA) system, are significantly affected by instrumental and ionospheric distortions. Recent developments in calibration techniques have enabled routine production of high-fidelity images at these challenging frequencies. The aim of this paper is to obtain images of the radio sources included in the Third Cambridge catalog, second revised version (3CRR) at an observing frequency of 58MHz, with an angular resolution of approximately 15arcsec and sensitivity to both compact and diffuse radio emission. This work also aims to produce accurate flux measurements for all sources. This dataset is designed to serve as a reference for low-frequency radio galaxy studies and future spectral aging analyses. We present the data reduction and calibration procedures developed for narrowband observations of bright sources with the LOFAR LBA. These include tailored direction-independent calibration strategies optimized for mitigating ionospheric phase corruptions and instrumental effects at 58~MHz. Imaging techniques were refined to reliably recover both small- and large-scale radio structures reliably. We deliver 58MHz radio images for the complete 3CRR sample, with flux density measurements exhibiting an average uncertainty of 10%. These results offer new insights into the energetics and evolution of radio galaxies at low frequencies. We also provide high-resolution models of these sources which is useful for calibrating future surveys. This legacy survey significantly expands the available high-resolution data at low frequencies and is the first fully imaged high-resolution sample at ultra low frequencies (<100MHz). It lays the foundation for future studies of radio galaxy physics, low-energy cosmic-ray populations, and the interplay between radio jets and their environments.

Cone search capability for table J/A+A/704/A65/tablec1 (3CRR catalogue observed at 58 MHz)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/A+A/704/A65
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/704/A65
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/704/A65
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/A+A/704/A65
Provenance
Creator Boxelaarlaar J.M.; De Gasperin F.; Hardcastle M.J.; Croston J.H.,Morabito L.K.; van Weeren R.J.; Edler H.
Publisher CDS
Publication Year 2025
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Cosmology; Galactic and extragalactic Astronomy; Natural Sciences; Observational Astronomy; Physics