Dark Energy Survey Year 1 results: Measurement of the galaxy angular power spectrum

H, Camacho and N, Kokron and Desai, Shantanu and et al, . (2019) Dark Energy Survey Year 1 results: Measurement of the galaxy angular power spectrum. Monthly Notices of the Royal Astronomical Society, 487 (3). pp. 3870-3883. ISSN 0035-8711

Full text not available from this repository. (Request a copy)

Abstract

We use data from the first-year observations of the DES collaboration to measure the galaxy angular power spectrum (APS), and search for its BAO feature. We test our methodology in a sample of 1800 DES Y1-like mock catalogues. We use the pseudo-Cl method to estimate the APS and the mock catalogues to estimate its covariance matrix. We use templates to model the measured spectra and estimate template parameters firstly from the Cl's of the mocks using two different methods, a maximum likelihood estimator and a Markov Chain Monte Carlo, finding consistent results with a good reduced χ2. Robustness tests are performed to estimate the impact of different choices of settings used in our analysis. Finally, we apply our method to a galaxy sample constructed from DES Y1 data specifically for LSS studies. This catalogue comprises galaxies within an effective area of 1318 deg2 and 0.6 < z < 1.0. We find that the DES Y1 data favour a model with BAO at the $2.6 σ C.L. However, the goodness of fit is somewhat poor, with χ2/(d.o.f.) = 1.49. We identify a possible cause showing that using a theoretical covariance matrix obtained from Cl's that are better adjusted to data results in an improved value of χ2/(dof) = 1.36 which is similar to the value obtained with the real-space analysis. Our results correspond to a distance measurement of DA(zeff = 0.81)/rd = 10.65 ± 0.49, consistent with the main DES BAO findings. This is a companion paper to the main DES BAO article showing the details of the harmonic space analysis.

[error in script]
IITH Creators:
IITH CreatorsORCiD
Desai, Shantanuhttp://orcid.org/0000-0002-0466-3288
Item Type: Article
Uncontrolled Keywords: cosmology: observations, large-scale structure of Universe, Indexed in Scopus
Subjects: Physics
Divisions: Department of Physics
Depositing User: Library Staff
Date Deposited: 01 Oct 2019 06:50
Last Modified: 01 Oct 2019 06:50
URI: http://raiithold.iith.ac.in/id/eprint/6454
Publisher URL: http://doi.org/10.1093/mnras/stz1514
Related URLs:

Actions (login required)

View Item View Item
Statistics for RAIITH ePrint 6454 Statistics for this ePrint Item