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Person# Zheng Zheng

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Johan Comparat, Jean-Paul Richard Kneib, Anand Stéphane Raichoor, Amélie Tamone, Andrei Variu, Yuting Wang, Cheng Zhao, Zheng Zheng

We present the cosmological implications from final measurements of clustering using galaxies, quasars, and Ly alpha forests from the completed Sloan Digital Sky Survey (SDSS) lineage of experiments in large-scale structure. These experiments, composed of data from SDSS, SDSS-II, BOSS, and eBOSS, offer independent measurements of baryon acoustic oscillation (BAO) measurements of angular-diameter distances and Hubble distances relative to the sound horizon, r(d), from eight different samples and six measurements of the growth rate parameter, f sigma(g), from redshift-space distortions (RSD). This composite sample is the most constraining of its kind and allows us to perform a comprehensive assessment of the cosmological model after two decades of dedicated spectroscopic observation. We show that the BAO data alone are able to rule out dark-energy-free models at more than eight standard deviations in an extension to the flat, Lambda CDM model that allows for curvature. When combined with Planck Cosmic Microwave Background (CMB) measurements of temperature and polarization, under the same model, the BAO data provide nearly an order of magnitude improvement on curvature constraints relative to primary CMB constraints alone. Independent of distance measurements, the SDSS RSD data complement weak lensing measurements from the Dark Energy Survey (DES) in demonstrating a preference for a flat Lambda CDM cosmological model when combined with Planck measurements. The combined BAO and RSD measurements indicate a sigma(g) = 0.85 +/- 0.03, implying a growth rate that is consistent with predictions from Planck temperature and polarization data and with General Relativity. When combining the results of SDSS BAO and RSD, Planck, Pantheon Type Ia supernovae (SNe Ia), and DES weak lensing and clustering measurements, all multiple-parameter extensions remain consistent with a Lambda CDM model. Regardless of cosmological model, the precision on each of the three parameters, Omega(Lambda), H-0, and sigma(g), remains at roughly 1%, showing changes of less than 0.6% in the central values between models. In a model that allows for free curvature and a time-evolving equation of state for dark energy, the combined samples produce a constraint Omega(k) = -0.0022 +/- 0.0022. The dark energy constraints lead to w(0) = -0.909 +/- 0.081 and w(a) = -049(-0.30)(+0.35), corresponding to an equation of state of w(p) = -1.018 +/- 0.032 at a pivot redshift z(p) = 0.29 and a Dark Energy Task Force Figure of Merit of 94. The inverse distance ladder measurement under this model yields H-0 = 68.18 +/- 0.79 km s(-1) Mpc(-1) , remaining in tension with several direct determination methods; the BAO data allow Hubble constant estimates that are robust against the assumption of the cosmological model. In addition, the BAO data allow estimates of H-0 that are independent of the CMB data, with similar central values and precision under a Lambda CDM model. Our most constraining combination of data gives the upper limit on the sum of neutrino masses at Sigma m(v) < 0.115 eV (95% confidence). Finally, we consider the improvements in cosmology constraints over the last decade by comparing our results to a sample representative of the period 2000-2010. We compute the relative gain across the five dimensions spanned by w, Omega(k) , Sigma m(v),H-0, and sigma(g) and find that the SDSS BAO and RSD data reduce the total posterior volume by a factor of 40 relative to the previous generation. Adding again the Planck, DES, and Pantheon SN Ia samples leads to an overall contraction in the five-dimensional posterior volume of 3 orders of magnitude.

Guillaume Blanc, Yuguang Chen, Johan Comparat, Amy Jones, Jean-Paul Richard Kneib, Cheng Li, David Schlegel, Yue Shen, Kai Zhang, Cheng Zhao, Zheng Zheng

This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated value-added catalogs. This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper, Local Volume Mapper, and Black Hole Mapper surveys.

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We study the evolution of star-forming galaxies with 10(10)M(circle dot) < M-* < 10(11.6)M(circle dot) over the redshift range of 0.7 < z < 1.2 using the emission-line galaxies (ELGs) in the extended Baryon Oscillation Spectroscopic Survey (eBOSS). By applying the incomplete conditional stellar mass function (SMF) model proposed in Guo et al., we simultaneously constrain the sample completeness, the stellar-halo mass relation (SHMR), and the quenched galaxy fraction. We obtain the intrinsic SMFs for star-forming galaxies in the redshift bins of 0.7 < z < 0.8, 0.8 < z < 0.9, 0.9 < z < 1.0, and 1.0 < z < 1.2, as well as the SMF for all galaxies in the redshift bin of 0.7 < z