2025/07/21 by Laura Bisigello, Marika Giulietti, L., Bisigello +15 · 1 voice
Physics and Astronomy · #Astronomy and Astrophysical Research #Gamma-ray bursts and supernovae #Astrophysics and Cosmic Phenomena
paper · doi:10.33232/001c.142496
openalex publication_date 2025/07/23 · openalex created_date 2025/07/24 · openalex updated_date 2026/07/28
We present a catalogue of optical and near-infrared counterparts to radio sources detected in the Euclid Deep Field North (EDF-N) using observations from the LOw-Frequency ARray (LOFAR) High Band Antenna (HBA) at 144 MHz with 6” angular resolution. The catalogue covers a circular region of and includes 23309 radio sources with a peak signal-to-noise ratio greater than 5. After masking regions close to stars and with unreliable photometry in the optical or near-infrared, the catalogue includes 19550 sources. To carry out a robust identification strategy, we combined the statistical power of the Likelihood Ratio (LR) method, including both colour and magnitude information, with targeted visual inspection. The resulting catalogue boasts a remarkable identification rate of 99.2%, successfully matching 19401 out of 19550 radio sources with reliable optical and/or near-infrared counterparts. For 19391 of the matched sources, we successfully derived photometric redshift for the host galaxy by performing an SED fit using the available data in the optical, near-infrared, far-infrared, and radio. LOFAR sources within the catalogue exhibit a median redshift of 1.1, with some extending up to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mi>z</mml:mi> <mml:mo>=</mml:mo> <mml:mn>6</mml:mn> </mml:mrow> </mml:math> . Around 7% of the sample is detected only in infrared using IRAC and tends towards higher redshifts, with a median of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mi>z</mml:mi> <mml:mo>=</mml:mo> <mml:mn>3.0</mml:mn> </mml:mrow> </mml:math> . This comprehensive catalogue serves as a valuable resource for future research, enabling detailed investigations into the properties and evolution of LOFAR-detected sources and their host galaxies.