Unbiased Cosmological Parameter Estimation from Emission Line Surveys with Interlopers

Abstract

The galaxy catalogs generated from low-resolution emission line surveys often contain both foreground and background interlopers due to line misidentification, which can bias the cosmological parameter estimation. In this paper, we present a method for correcting the interloper bias by using the joint-analysis of auto- and cross-power spectra of the main and the interloper samples. In particular, we can measure the interloper fractions from the cross-correlation between the interlopers and survey galaxies, because the true cross-correlation must be negligibly small. The estimated interloper fractions, in turn, remove the interloper bias in the cosmological parameter estimation. For example, in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) low-redshift ($z<0.5$) [O II] $\lambda 3727$Å emitters contaminate high-redshift ($1.9<z<3.5$) Lyman-$\alpha$ line emitters. We demonstrate that the joint-analysis method yields a high signal-to-noise ratio measurement of the interloper fractions while only marginally increasing the uncertainties in the cosmological parameters relative to the case without interlopers. We also show the same is true for the high-latitude spectroscopic survey of Wide-Field Infrared Survey Telescope (WFIRST) mission where contamination occurs between the Balmer-$\alpha$ line emitters at lower redshifts ($1.1<z<1.9$) and Oxygen ([O III] $\lambda 5007$Å) line emitters at higher redshifts ($1.7<z<2.8$).

arXiv comment36 pages, 26 figures

References in corpus (46)

• Planck 2015 results. XIII. Cosmological parameters
• Detection of the Baryon Acoustic Peak in the Large-Scale Correlation Function of SDSS Luminous Red Galaxies
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The 2dF Galaxy Redshift Survey: Power-spectrum analysis of the final dataset and cosmological implications
• Large-Scale Structure of the Universe and Cosmological Perturbation Theory
• First results from the IllustrisTNG simulations: matter and galaxy clustering
• Observational Probes of Cosmic Acceleration
• Acoustic Signatures in the Primary Microwave Background Bispectrum
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Power Spectrum Analysis of Three-Dimensional Redshift Surveys
• Cosmology and fundamental physics with the Euclid satellite
• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Large-Scale Galaxy Bias
• Probing Dark Energy with Baryonic Acoustic Oscillations from Future Large Galaxy Redshift Surveys
• The 3D-HST Survey: Hubble Space Telescope WFC3/G141 grism spectra, redshifts, and emission line measurements for $\sim 100,000$ galaxies
• 3D-HST: A wide-field grism spectroscopic survey with the Hubble Space Telescope
• Extragalactic Science, Cosmology and Galactic Archaeology with the Subaru Prime Focus Spectrograph (PFS)
• The LOFAR Two-metre Sky Survey - II. First data release
• Probing dark energy using baryonic oscillations in the galaxy power spectrum as a cosmological ruler
• Fingers of God
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• New Perspective on Galaxy Clustering as a Cosmological Probe: General Relativistic Effects
• Improved forecasts for the baryon acoustic oscillations and cosmological distance scale
• Large-scale clustering of galaxies in general relativity
• Redshifting Rings of Power
• Perturbation Theory Reloaded: Analytical Calculation of Non-linearity in Baryonic Oscillations in the Real Space Matter Power Spectrum
• Lyman-Alpha-Emitting Galaxies at z = 2.1 in ECDF-S: Building Blocks of Typical Present-day Galaxies?
• High-precision predictions for the acoustic scale in the non-linear regime
• Slicing COSMOS with SC4K: the evolution of typical Lya emitters and the Lya escape fraction from z~2 to z~6
• Asymmetric galaxy correlation functions
• Constraining Anisotropic Baryon Oscillations
• The Evolution of Ly-alpha Emitting Galaxies Between z = 2.1 and z = 3.1
• The extended Baryon Oscillation Spectroscopic Survey (eBOSS): a cosmological forecast
• Perturbation Theory Reloaded II: Non-linear Bias, Baryon Acoustic Oscillations and Millennium Simulation In Real Space
• The 0.1<z<1.65 evolution of the bright end of the [OII] luminosity function
• On Removing Interloper Contamination from Intensity Mapping Power Spectrum Measurements
• Extracting Angular Diameter Distance and Expansion Rate of the Universe from Two-dimensional Galaxy Power Spectrum at High Redshifts: Baryon Acoustic Oscillation Fitting versus Full Modeling
• Spectral Line De-confusion in an Intensity Mapping Survey
• Forecasting the Cosmological Constraints with Anisotropic Baryon Acoustic Oscillations from Multipole Expansion
• Total Angular Momentum Waves for Scalar, Vector, and Tensor Fields
• The HETDEX Pilot Survey. IV. The Evolution of [O II] Emitting Galaxies from z ~ 0.5 to z ~ 0
• Large-Scale Structure Observables in General Relativity
• Interloper bias in future large-scale structure surveys
• Bayesian Redshift Classification of Emission-line Galaxies with Photometric Equivalent Widths
• Galaxy redshift surveys with sparse sampling
• Probing Dark Energy with Baryonic Acoustic Oscillations at High Redshifts

Cited by in corpus (18)

• The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Survey Design, Reductions, and Detections
• Euclid: Forecasts from redshift-space distortions and the Alcock-Paczynski test with cosmic voids
• HETDEX Public Source Catalog 1: 220K Sources Including Over 50K Lyman Alpha Emitters from an Untargeted Wide-area Spectroscopic Survey
• Cosmology with dropout selection: Straw-man surveys and CMB lensing
• The degeneracy between primordial non-Gaussianity and foregrounds in 21cm intensity mapping experiments
• Correcting correlation functions for redshift-dependent interloper contamination
• The HETDEX Survey: Emission Line Exploration and Source Classification
• The Impact of Line Misidentification on Cosmological Constraints from Euclid and other Spectroscopic Galaxy Surveys
• Nonlinear Redshift-Space Distortions in the Harmonic-space Galaxy Power Spectrum
• Line confusion in spectroscopic surveys and its possible effects: Shifts in Baryon Acoustic Oscillations position
• Searching for dark energy in the matter-dominated era
• High-redshift cosmology with oxygen lines from H$\alpha$ surveys
• Fast Calculation of Nonlinear Redshift-space Galaxy Power Spectrum Including Selection Bias
• Precise self-calibration of interloper bias in spectroscopic surveys
• Photometric IGM tomography with Subaru/HSC: the large-scale structure of Ly$\alpha$ emitters and IGM transmission in the COSMOS field at $z\sim 5$
• Separating Angular and Radial Modes with Spherical-Fourier Bessel Power Spectrum on All Scales and Implications for Systematics Mitigation
• Removal of interloper contamination to line-intensity maps using correlations with ancillary tracers of the large-scale structure
• A novel analysis of contamination in Lyman-break galaxy samples at $\mathbf{z}\sim 6-8$: spatial correlation with intermediate-redshift galaxies at $\mathbf{z}\sim 1.3-2$