Quasar photometric redshifts from incomplete data using deep learning

نویسندگان

چکیده

Forthcoming astronomical surveys are expected to detect new sources in such large numbers that measuring their spectroscopic redshift measurements will be not practical. Thus, there is much interest using machine learning yield the from photometry of each object. We particularly interested radio (quasars) detected with Square Kilometre Array and have found Deep Learning, trained upon a optically-selected sample quasi-stellar objects, effective prediction redshifts three external samples radio-selected sources. However, requirement nine different magnitudes, near-infrared, optical ultra-violet bands, has effect significantly reducing number for which can predicted. Here we explore possibility impute missing features. find training sample, simple imputation sufficient, replacing magnitude maximum band, thus presuming non-detection at sensitivity limit. For test samples, however, this does perform as well multivariate imputation, suggests many magnitudes limits, but indeed been observed. From extensive testing models, suggest best restricted two values per source. Where overlap on sky, worst case, increases fraction estimated 46% 80%, >90% being reached other samples.

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ژورنال

عنوان ژورنال: Monthly Notices of the Royal Astronomical Society

سال: 2022

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

DOI: https://doi.org/10.1093/mnras/stac660