Removing Imaging Systematics from Galaxy Clustering Measurements with Obiwan : Application to the SDSS-IV extended Baryon Oscillation Spectroscopic Survey Emission Line Galaxy Sample

Abstract

This work presents the application of a new tool, Obiwan , which uses image simulations to determine the selection function of a galaxy redshift survey and calculate 3-dimensional (3D) clustering statistics. This is a forward model of the process by which images of the night sky are transformed into a 3D large--scale structure catalog. The photometric pipeline automatically detects and models galaxies and then generates a catalog of such galaxies with detailed information for each one of them, including their location, redshift and so on. Systematic biases in the imaging data are therefore imparted into the catalogs and must be accounted for in any scientific analysis of their information content. Obiwan simulates this process for samples selected from the Legacy Surveys imaging data. This imaging data will be used to select target samples for the next-generation Dark Energy Spectroscopic Instrument (DESI) experiment. Here, we apply Obiwan to a portion of the SDSS-IV extend Baryon Oscillation Spectroscopic Survey Emission Line Galaxies (ELG) sample. Systematic biases in the data are clearly identified and removed. We compare the 3D clustering results to those obtained by the map--based approach applied to the full eBOSS sample. We find the results are consistent, thereby validating the eBOSS ELG catalogs, presented in Raichoor(2020), used to obtain cosmological results.

arXiv comment18 pages, 19 figures

References in corpus (42)

• The Sloan Digital Sky Survey: Technical Summary
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• The 2dF Galaxy Redshift Survey: Spectra and redshifts
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• The Sixteenth Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra
• Observational Probes of Cosmic Acceleration
• The DESI Experiment Part I: Science,Targeting, and Survey Design
• The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
• The Dark Energy Camera
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data
• The DEEP2 Galaxy Redshift Survey: Design, Observations, Data Reduction, and Redshifts
• The WiggleZ Dark Energy Survey: Survey Design and First Data Release
• The Updated Zwicky Catalog (UZC)
• The VIMOS VLT Deep Survey - First epoch VVDS-Deep survey: 11564 spectra with 17.5<=IAB<=24, and the redshift distribution over 0< z <=5
• The VIMOS VLT Deep Survey final data release: a spectroscopic sample of 35016 galaxies and AGN out to z~6.7 selected with 17.5<=i_{AB}<=24.7
• Statistical Analysis of Galaxy Surveys - I. Robust error estimation for 2-point clustering statistics
• Dark Energy Survey Year 1 Results: Constraints on Extended Cosmological Models from Galaxy Clustering and Weak Lensing
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic correlation function between redshifts 0.6 and 1
• The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Analysis of potential systematics
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Observational systematics and baryon acoustic oscillations in the correlation function
• The DESI Experiment Part II: Instrument Design
• Measuring the galaxy power spectrum with future redshift surveys
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Quasar Target Selection
• Ameliorating Systematic Uncertainties in the Angular Clustering of Galaxies: A Study using SDSS-III
• EZmocks: extending the Zel'dovich approximation to generate mock galaxy catalogues with accurate clustering statistics
• First Measurement of the Clustering Evolution of Photometrically-Classified Quasars
• Clustering of Sloan Digital Sky Survey III Photometric Luminous Galaxies: The Measurement, Systematics and Cosmological Implications
• Dark Energy Survey Year 1 Results: Galaxy clustering for combined probes
• Clustering of quasars in SDSS-IV eBOSS : study of potential systematics and bias determination
• The SDSS-IV extended Baryonic Oscillation Spectroscopic Survey: Luminous Red Galaxy Target Selection
• The WiggleZ Dark Energy Survey: the selection function and z=0.6 galaxy power spectrum
• No galaxy left behind: accurate measurements with the faintest objects in the Dark Energy Survey
• The SDSS-IV Extended Baryon Oscillation Spectroscopic Survey: final Emission Line Galaxy Target Selection
• Estimating the large-scale angular power spectrum in the presence of systematics: a case study of Sloan Digital Sky Survey quasars
• Exact likelihood evaluations and foreground marginalization in low resolution WMAP data
• Clustering properties of $g$-selected galaxies at $z\sim 0.8$
• Angular correlation function of 1.5 million LRGs: clustering evolution and a search for BAO
• Unbiased methods for removing systematics from galaxy clustering measurements
• The SDSS-IV eBOSS: emission line galaxy catalogues at z=0.8 and study of systematic errors in the angular clustering
• Observing Strategy for the Legacy Surveys

Cited by in corpus (15)

• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Cosmological Implications from two Decades of Spectroscopic Surveys at the Apache Point observatory
• Target Selection and Validation of DESI Emission Line Galaxies
• The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Large-scale Structure Catalogues and Measurement of the isotropic BAO between redshift 0.6 and 1.1 for the Emission Line Galaxy Sample
• Dark Energy Survey Year 3 Results: Measuring the Survey Transfer Function with Balrog
• The Dark Energy Camera Plane Survey 2 (DECaPS2): More Sky, Less Bias, and Better Uncertainties
• Detecting clusters of galaxies and active galactic nuclei in an eROSITA all-sky survey digital twin
• Mitigating contamination in LSS surveys: a comparison of methods
• Unveiling the Intrinsic Alignment of Galaxies with Self-Calibration and DECaLS DR3 data
• Angular clustering properties of the DESI QSO target selection using DR9 Legacy Imaging Surveys
• Local primordial non-Gaussianity from the large-scale clustering of photometric DESI luminous red galaxies
• Using angular two-point correlations to self-calibrate the photometric redshift distributions of DECaLS DR9
• Intrinsic Alignment as an RSD Contaminant in the DESI Survey
• Covariance matrices for variance-suppressed simulations
• Cross-correlation between soft X-rays and galaxies A new benchmark for galaxy evolution models
• Weak Lensing Reconstruction by Counting DECaLS Galaxies