Results 81 to 90 of about 219,246 (225)
Frontiers in Astronomy and Space Sciences, 2023 In response to all current cosmological controversies, this paper provides a reliable explanation of the Hubble tension and of the apparent acceleration of space expansion detected by SN Ia.
Alessandro Trinchera
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Photometric Redshifts of Quasars
The Astronomical Journal, 2001 We demonstrate that the design of the Sloan Digital Sky Survey (SDSS) filter system and the quality of the SDSS imaging data are sufficient for determining accurate and precise photometric redshifts (``photo-z''s) of quasars. Using a sample of 2625 quasars, we show that photo-z determination is even possible for z<=2.2 despite the lack of a strong ...
Tamás Budavári +39 more
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A Catalog of Photometric Redshift and the Distribution of Broad Galaxy Morphologies
Galaxies, 2018 We created a catalog of photometric redshift of ∼3,000,000 SDSS galaxies annotated by their broad morphology. The photometric redshift was optimized by testing and comparing several pattern recognition algorithms and variable selection strategies, and ...
Nicholas Paul +2 more
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Redshift in Finsler spacetimes [PDF]
Physical Review D, 2019 We derive and discuss a general redshift formula in Finsler spacetimes. The condition for the existence of a redshift potential is worked out. The results are illustrated with two examples, one refering to a spherically symmetric and static Finsler spacetime and the other to a cosmological Finsler spacetime.
Wolfgang Hasse, Volker Perlick
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, 2020 Can redshift errors bias our measurement of the Hubble constant? This talk outlines some common errors in redshift measurements, in particular some common theoretical errors that should be avoided, and assesses how such errors can impact cosmological parameter inferences.
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Galaxies at High Redshift [PDF]
Astrophysics and Space Science, 1999 Within just the last few years, we have advanced from knowing only a few galaxies at z>2 to having redshifts for nearly 1000 z~2-5 objects. The majority of this sample has been detected through the photometric ``drop-out'' technique used so successfully by Steidel and his collaborators. In addition, a handful of objects have already been detected at
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Luminosity-Environment Relation in the Lowz Sample of the SDSS-III
Open Astronomy, 2016 In this work, we examine the environmental dependence of the u-, g-, r-, i- and z-band luminosities in the LOWZ sample of the Sloan Digital Sky Survey Data Release 10 (SDSS DR10).
Deng Xin-Fa +6 more
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Morphological evolution in situ: Disk-dominated cluster red sequences at z ~ 1.25
, 2015 We have carried out a joint photometric and structural analysis of red sequence galaxies in four clusters at a mean redshift of z ~ 1.25 using optical and near-IR HST imaging reaching to at least 3 magnitudes fainter than $M^*$.
Bremer, M. N. +2 more
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On the Number of Galaxies at High Redshift
Galaxies, 2015 The number of galaxies at a given flux as a function of the redshift, z, is derived when the z-distance relation is non-standard. In order to compare different models, the same formalism is also applied to the standard cosmology.
Lorenzo Zaninetti
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Study of star-forming galaxies in SDSS up to redshift 0.4: I. Metallicity evolution
, 2009 The chemical composition of the gas in galaxies versus cosmic time provides a very important tool for understanding galaxy evolution. Although there are many studies at high redshift, they are rather scarce at lower redshifts.
Bongiovanni, A. +7 more
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