Deep field catalogues & images — ELAIS-N1

Readme file

The following README file provides a description of the various files released for Elais-N1 in this data release.

File nameDescription
en1_README.txtREADME file

Radio data and raw catalogues

The following files provide the radio data, plus the raw source and Gaussian catalogues produced by PyBDSF (prior to any source association) Further datasets and catalogues may be available on request (e.g. catalogues per observation date, polarisation data). For further details see Sabater et al 2021 ( ). For any questions, please contact Jose Sabater (

File nameDescription
en1_radio_image.fitsPrimary beam corrected radio image (crop)
en1_radio_rms_image.fitsRadio RMS image
en1_pybdsf_source.fitsInitial PyBDSF source list
en1_pybdsf_gaussian.fitsInitial PyBDSF Gaussian component list
en1_columns_pybdsf_source.mdColumn description file for pybdsf_source.fits

Optical images and catalogues

The following files provide the multi-wavelength data in three key bands, plus the full combined optical/IR catalogue presented by Kondapally et al. (2021) ( ). Details on the creation of the multi-band mosaics, the photometry catalogues, and the recommended quality/flag cuts are outlined in Section 3 of Kondapally et al. (2021) and in the README . All magnitudes provided are in the AB system. For further information regarding the multi-wavelength data see Kondapally et al or contact Rohit Kondapally ( Raw photometry is provided in 8 circular apertures, and in addition, photometry in our recommended aperture sizes, corrected for both aperture and Galactic extinction effects is also provided. The multi-band mosaics have a magnitude zero-point of 30mag in the AB system.

File nameDescription
en1_image_iband.fitsPanSTARRS i-band mosaic
en1_image_Kband.fitsUKIDSS-DXS K-band image (from DR10)
en1_image_4.5band.fitsSpitzer SWIRE 4.5 band mosaic
en1_optIR_catalogue_full.fitsThe full combined chi2 detected optical/IR catalogue
en1_columns_optIR_catalogue_full.mdColumn description file for optIR_catalogue_full.fits

Photometric redshifts and science-ready multi-wavelength data

The following files provide the photometric redshifts as provided in Duncan et al. (2020: ). Details of the photometric redshift and stellar mass (limited to z < 1.5) estimation are outlined in the paper, as well as guidance on the parameter space within which these values can be trusted. Additional information regarding the definition of the photometric redshift columns can also be found in Section 4 of Duncan et al. (2019a: ). Columns providing Herschel far-IR information for the full optical catalogs are provided by the Herschel Extragalactic Legacy Project (HELP; ) - to we which refer the reader for additional information regarding methodology and column definition. The revised 24-500um flux information for the LOFAR source population (as provided in the final cross-matched catalogues below) is presented in McCheyne et al. (in prep.). Additionally, full panchromatic spectral energy distribution fitting for the LOFAR detected population that accounts for AGN contributions and far-IR emission will be presented separately in Best et al. (in prep.).

File nameDescription
en1_optIR_catalogue_science_ready_photoz.fitsThe science ready catalogues with photo-z, spec-z's and stellar masses (where available)
en1_columns_optIR_catalogue_science_ready_photoz.mdColumns description file for the optIR_catalogue_science_ready_photoz.fits

Source-associated and cross-matched data

The following files provide the radio catalogues resulting from source association and cross-matching, as detailed in Section 4 of Kondapally et al. (2021) ( ). This process was carried out over the regions of the field with best-quality overlapping multi-wavelength data (see README file for details of quality/flag cuts used). See Kondapally et al for further information.

File nameDescription
en1_pybdsf_source_lr.fitsInitial PyBDSF source list with Likelihood Ratio only and workflow information
en1_final_cross_match_catalogue-v1.0.fitsFinal cross-matched radio catalogue with key optical host galaxy properties
en1_final_component_catalogue-v1.0.fitsFinal component radio catalogue, after source association and deblending
en1_columns_final_cross_match_catalogue.mdColumn description file for final_cross_match_catalogue-v1.0.fits
en1_columns_final_component_catalogue.mdColumn description file for final_component_catalogue-v1.0.fits

Mask and MOC files

The following files provide nan-masked radio RMS images generated based on the coverage of the overlapping multi-wavelength data in the field and bright-star masking (based on both Spitzer and optical detections). The overlapping multi-wavelength coverage and the details of the bright-star mask generation are provided in Section 3 and Appendix B of Kondapally et al. (2021) ( ). The multi-order coverage (MOC) maps corresponding to the masks are also provided.

File nameDescription
en1_rms_starmask_optical.fitsNaN masked radio RMS map with information about multi-wavelength overlap coverage and bright star masks (star masking based on --optical-- detections)
en1_rms_starmask_spitzer.fitsNaN masked radio RMS map with information about multi-wavelength overlap coverage and bright star masks (star masking based on --Spitzer-- detections)
en1_starmask_optical_MOC.fitsMOC file indicating star mask regions based on optical detections (conservative mask; use in rms_starmask_optical.fits)
en1_starmask_spitzer_MOC.fitsMOC file indicating star mask regions based on Spitzer detections (restrictive mask; use in rms_starmask_spitzer.fits)