Improving the reliability of photometric redshift with machine learning

نویسندگان

چکیده

In order to answer the open questions of modern cosmology and galaxy evolution theory, robust algorithms for calculating photometric redshifts (photo-z) very large samples galaxies are needed. Correct estimation various photo-z algorithms' performance requires attention both metrics data used estimation. this work, we use supervised machine learning algorithm MLPQNA calculate in COSMOS2015 catalogue unsupervised Self-Organizing Maps (SOM) determine reliability resulting estimates. We find that spec-z<1.2, predictions on same level quality as SED fitting photo-z. show SOM successfully detects unreliable spec-z cause biases performance. Additionally, select objects with reliable predictions. Our cleaning procedures allow extract subset which final catalogs is improved by a factor two, compared overall statistics.

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ژورنال

عنوان ژورنال: Monthly Notices of the Royal Astronomical Society

سال: 2021

ISSN: ['0035-8711', '1365-8711', '1365-2966']

DOI: https://doi.org/10.1093/mnras/stab2334