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Critical Examinations of QSO Redshift Periodicities and Associations with Galaxies in Sloan Digital Sky Survey Data

Su Min Tang·Shuang Nan Zhang
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Abstract

We have used the publicly available data from the Sloan Digital Sky Survey and 2dF QSO Redshift Survey to test the hypothesis that QSOs are ejected from active galaxies with periodic non-cosmological redshifts. For two different intrinsic redshift models, namely the Karlsson $\log(1+z)$ model and Bell's decreasing intrinsic redshift (DIR) model, we do two tests respectively. First, using different criteria, we generate four sets of QSO-galaxy pairs and find there is no evidence for a periodicity at the predicted frequency in $\log(1+z)$, or at any other frequency. We then check the relationship between high redshift QSOs and nearby active galaxies, and we find the distribution of projected distance between high redshift QSOs and nearby active galaxies and the distribution of redshifts of those active galaxies are consistent with a distribution of simulated random pairs, completely different from Bell's previous conclusion. We also analyze the periodicity in redshifts of QSOs, and no periodicity is found in high completeness samples, contrary to the DIR model. These results support that QSOs are not ejected from active galaxies.

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Su Min Tang, Shuang Nan Zhang. 2005-06-16. Critical Examinations of QSO Redshift Periodicities and Associations with Galaxies in Sloan Digital Sky Survey Data. https://doi.org/10.1086/432754

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