Search arXiv⌕ Search

arXiv · 2012.12826

Dark Energy Survey Year 3 Results: Calibration of Lens Sample Redshift Distributions using Clustering Redshifts with BOSS/eBOSS

Abstract

We present clustering redshift measurements for Dark Energy Survey (DES) lens sample galaxies to be used in weak gravitational lensing and galaxy clustering studies. To perform this measurement, we cross-correlate with spectroscopic galaxies from the Baryon Acoustic Oscillation Survey (BOSS) and its extension, eBOSS. We validate our methodology in simulations, including a new technique to calibrate systematic errors due to the galaxy clustering bias, finding our method to be generally unbiased in calibrating the mean redshift. We apply our method to the data, and estimate the redshift distribution for eleven different photometrically-selected bins. We find general agreement between clustering redshift and photometric redshift estimates, with differences on the inferred mean redshift to be below $|Δz|=0.01$ in most of the bins. We also test a method to calibrate a width parameter for redshift distributions, which we found necessary to use for some of our samples. Our typical uncertainties on the mean redshift ranged from 0.003 to 0.008, while our uncertainties on the width ranged from 4 to 9\%. We discuss how these results calibrate the photometric redshift distributions used in companion DES Year 3 Results papers.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R. Cawthon, J. Elvin-Poole, A. Porredon, M. Crocce, G. Giannini, M. Gatti, A. J. Ross, E. S. Rykoff, A. Carnero Rosell, J. DeRose, S. Lee, M. Rodriguez-Monroy, A. Amon, K. Bechtol, J. De Vicente, D. Gruen, R. Morgan, E. Sanchez, J. Sanchez, I. Sevilla-Noarbe, T. M. C. Abbott, M. Aguena, S. Allam, J. Annis, S. Avila, D. Bacon, E. Bertin, D. Brooks, D. L. Burke, M. Carrasco Kind, J. Carretero, F. J. Castander, A. Choi, M. Costanzi, L. N. da Costa, M. E. S. Pereira, K. Dawson, S. Desai, H. T. Diehl, K. Eckert, S. Everett, I. Ferrero, P. Fosalba, J. Frieman, J. García-Bellido, E. Gaztanaga, R. A. Gruendl, J. Gschwend, G. Gutierrez, S. R. Hinton, D. L. Hollowood, K. Honscheid, D. Huterer, D. J. James, A. G. Kim, J. -P. Kneib, K. Kuehn, N. Kuropatkin, O. Lahav, M. Lima, H. Lin, M. A. G. Maia, P. Melchior, F. Menanteau, R. Miquel, J. J. Mohr, J. Muir, J. Myles, A. Palmese, S. Pandey, F. Paz-Chinchón, W. J. Percival, A. A. Plazas, A. Roodman, G. Rossi, V. Scarpine, S. Serrano, M. Smith, M. Soares-Santos, E. Suchyta, M. E. C. Swanson, G. Tarle, C. To, M. A. Troxel, R. D. Wilkinson, the DES Collaboration. 2022-06-08. Dark Energy Survey Year 3 Results: Calibration of Lens Sample Redshift Distributions using Clustering Redshifts with BOSS/eBOSS. https://doi.org/10.1093/mnras%2Fstac1160

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Vacuum Polarization, Geodesic Equation and Sachs-Wolfe Effect

We show that the null geodesic equation for photons is modified in the presence of a charged scalar field, with quantum fluctuations acting as an effective mass term that changes the null paths to timelike curves. This effect can be interpreted as a vacuum polarization phenomenon in curved spacetime. The resulting contribution to the Sachs-Wolfe effect varies with photon frequency, leading to frequency-dependent corrections to the cosmic microwave background (CMB) blackbody spectrum in the form of a $μ$-distortion, as well as modifications to the CMB power spectrum. We estimate these within a standard inflationary scenario and find that while the correction to the CMB power spectrum is significant when the scalar field is light, the magnitude of the $μ$-distortion depends strongly on the regularization prescription.

astro-ph.CO↗

Testing Bump in the Cosmological Power Spectrum Using Dwarf Galaxies

We analyze the possibility of using observational data on nearby dwarf galaxies -- their luminosity functions and spatial distributions -- to constrain deviations of the cosmological power spectrum from the standard one. Specifically, we consider a cosmological model with a "bump" in the power spectrum at a wavelength of 1.3~Mpc and a dimensionless amplitude $\mathcal{A}=2.0$. Such a spectrum is motivated by observations of an excess number of galaxies at high redshifts. The bump leads to a noticeable increase in the luminosity function in the range $-13 > M_B > -17$ at $z=0$. Comparison with observations constrains the bump amplitude to $\mathcal{A} < 0.25$ at a 3-sigma significance level for a wavelength of 1.3~Mpc. For wavelengths smaller than 0.8~Mpc, the bump manifests only in the luminosity function of dwarfs with $M_B > -14$.

astro-ph.CO↗

Multi-tracers, multi-surveys: a joint Fisher analysis of DESI+PFS

Marginalizing over 11 effective-field-theory (EFT) nuisance parameters per tracer per redshift bin degrades cosmological precision in one-loop analyses of galaxy power-spectrum multipoles in redshift space. Simulation-based priors (SBP) tighten these parameters but rely on N-body simulations and halo-occupation-distribution (HOD) models. We consider a multi-tracer Fisher analysis as a complementary approach: auto- and cross-power spectra jointly constrain cosmology, galaxy bias and stochasticity through two channels -- within a survey and across overlapping surveys -- combined in a volume-partitioned joint Fisher analysis. We forecast across the $14{,}000\;\mathrm{deg}^2$ Dark Energy Spectroscopic Instrument (DESI) footprint, including the $\sim\!1{,}200\;\mathrm{deg}^2$ Prime Focus Spectrograph (PFS) overlap at $z\in[0.6,1.6]$ with up to 4 tracers (PFS-ELG, DESI-ELG, DESI-LRG, DESI-QSO). We vary a common $\ln(10^{10}A_s)$, $M_ν$ and $Ω_m$, holding $h$, $ω_b$ and $n_s$ fixed. Adding internal-DESI cross-spectra to DESI auto-spectra reduces the errors on the derived $fσ_8(z=1.1)$, $M_ν$ and $Ω_m$ by 7.1%, 3.5% and 3.8%, respectively, at $k_{\rm max}=0.20\,h\,\mathrm{Mpc}^{-1}$. Adding PFS auto- and cross-spectra to this complete DESI multi-tracer analysis further tightens these errors by 3.8%, 2.6% and 3.2%, respectively, after marginalizing over residual cross-population stochasticity. The clustering likelihood alone constrains the linear and quadratic biases and the shot noise. For these parameters it provides a complementary test of inference using SBP, while the counterterms remain weakly constrained. The framework extends to any number of overlapping spectroscopic surveys.

astro-ph.CO↗