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The K correction

David W. Hogg·Ivan K. Baldry·Michael R. Blanton·Daniel J. Eisenstein
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Abstract

The K correction "corrects" for the fact that sources observed at different redshifts are, in general, compared with standards or each other at different rest-frame wavelengths. It is part of the relation between the emitted- or rest-frame absolute magnitude of a source in one broad photometric bandpass to the observed-frame apparent magnitude of the same source in another broad bandpass. This short pedagogical paper provides definitions of and equations for the K correction.

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David W. Hogg, Ivan K. Baldry, Michael R. Blanton, Daniel J. Eisenstein. 2002-10-17. The K correction. https://arxiv.org/abs/astro-ph/0210394

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