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The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal
The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal
Physics Faculty Publications
We determine the 22 μm luminosity evolution and luminosity function for quasars from a data set of over 20,000 objects obtained by combining flux-limited Sloan Digital Sky Survey optical and Wide field Infrared Survey Explorer mid-infrared data. We apply methods developed in previous works to access the intrinsic population distributions non-parametrically, taking into account the truncations and correlations inherent in the data. We find that the population of quasars exhibits positive luminosity evolution with redshift in the mid-infrared, but with considerably less mid-infrared evolution than in the optical or radio bands. With the luminosity evolutions accounted for, we determine …
The Efficacy Of Galaxy Shape Parameters In Photometric Redshift Estimation: A Neural Network Approach, Jack Singal, M. Shmakova, B. Gerke, R. L. Griffith, J. Lotz
The Efficacy Of Galaxy Shape Parameters In Photometric Redshift Estimation: A Neural Network Approach, Jack Singal, M. Shmakova, B. Gerke, R. L. Griffith, J. Lotz
Physics Faculty Publications
We present a determination of the effects of including galaxy morphological parameters in photometric redshift estimation with an artificial neural network method. Neural networks, which recognize patterns in the information content of data in an unbiased way, can be a useful estimator of the additional information contained in extra parameters, such as those describing morphology, if the input data are treated on an equal footing. We use imaging and five band photometric magnitudes from the All-wavelength Extended Groth Strip International Survey. It is shown that certain principal components of the morphology information are correlated with galaxy type. However, we find …