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An Optical Multicolor System For Measuring Galaxy Redshifts And Spectral Types

Charles T. Liu·Richard F. Green
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Abstract

A method of obtaining approximate redshifts and spectral types of galaxies using a photometric system of six broad-bandpass filters is developed. The technique utilizes a smallest maximum difference approach rather than a least-squares approach, and does not consider a galaxy's apparent magnitude in the determination of its redshift. In an evalution of its accuracy using two distinct galaxy samples, the photometric redshifts are found to have a root mean square deviation of $\pm$0.05 from spectroscopically determined redshifts. Possible systematic errors of the method are investigated, including the effects of post-starburst (``E+A'') galaxies and attempts to measure redshifts with incomplete color information. Applications of the technique are discussed.

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Charles T. Liu, Richard F. Green. 1998-06-02. An Optical Multicolor System For Measuring Galaxy Redshifts And Spectral Types. https://doi.org/10.1086/300480

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