minijpas_public_data_release_pdr201912 pdr201912_new_lephare_photoz

Updated Photometric redshifts with LePhare

The table 'minijpas.PhotoZLephare_updated' contains photometric redshifts calculated with a custom version of LePhare (Arnouts & Ilbert 2011). This table supersedes 'minijpas.PhotoZLephare' and solves several issues found in 'minijpas.PhotoZLephare' after its public release (see below). The original table 'minijpas.PhotoZLephare' remains available for reference, but we strongly advise to use the updated version.

Changes in 'minijpas.PhotoZLephare_updated':

  • Solves bug in the implementation of the redshift prior caused PHOTOZ=0, Z_BEST68_LOW=0, and wrong Z_ML and PHOTOZ_ERR values in ~10% of sources. Redshifts, redshift errors and chi2 values are unchanged for unaffected sources.
  • Solves bug in the interpolation of the PDF caused the cumulative_PDF to be miscalculated in sources with very narrow PDF. cumulative_PDF is now deprecated in favor of full resolution PDFs given in compressed form (sparse_PDF, see below).
  • Statistical analysis of the PDFs showed that they overestimate the confidence of PHOTOZ for bright (r<19) sources and underestimate for faint (r>20) sources. A contrast-correction of the PDF now compensates for this effect.
  • As a consequence of the contrast correction, the odds parameter now reflects the probability of a redshift error |∆z|<0.03 irrespective of the magnitude of the source.
  • 'sparse_PDF' provides a compressed form (sparse basis representation) of the full resolution PDF (dz=0.002) after application of the contrast correction.