TY - JOUR
T1 - Euclid preparation XLI. Galaxy power spectrum modelling in real space
AU - Euclid Collaboration
AU - Pezzotta, A.
AU - Moretti, C.
AU - Zennaro, M.
AU - Dizgah, A. Moradinezhad
AU - Crocce, M.
AU - Sefusatti, E.
AU - Ferrero, I.
AU - Pardede, K.
AU - Eggemeier, A.
AU - Barreira, A.
AU - Angulo, R. E.
AU - Marinucci, M.
AU - Quevedo, B. Camacho
AU - de la Torre, S.
AU - Alkhanishvili, D.
AU - Biagetti, M.
AU - Breton, M. A.
AU - Castorina, E.
AU - D’Amico, G.
AU - Desjacques, V.
AU - Guidi, M.
AU - Kärcher, M.
AU - Oddo, A.
AU - Ibanez, M. Pellejero
AU - Porciani, C.
AU - Pugno, A.
AU - Salvalaggio, J.
AU - Sarpa, E.
AU - Veropalumbo, A.
AU - Vlah, Z.
AU - Amara, A.
AU - Andreon, S.
AU - Auricchio, N.
AU - Baldi, M.
AU - Bardelli, S.
AU - Bender, R.
AU - Bodendorf, C.
AU - Bonino, D.
AU - Branchini, E.
AU - Brescia, M.
AU - Brinchmann, J.
AU - Camera, S.
AU - Capobianco, V.
AU - Carbone, C.
AU - Cardone, V. F.
AU - Carretero, J.
AU - Casas, S.
AU - Castander, F. J.
AU - Castellano, M.
AU - Bernardeau, F.
N1 - Publisher Copyright:
© The Authors 2024.
PY - 2024/7/1
Y1 - 2024/7/1
N2 - We investigate the accuracy of the perturbative galaxy bias expansion in view of the forthcoming analysis of the Euclid spectroscopic galaxy samples. We compare the performance of a Eulerian galaxy bias expansion using state-of-the-art prescriptions from the effective field theory of large-scale structure (EFTofLSS) with a hybrid approach based on Lagrangian perturbation theory and high-resolution simulations. These models are benchmarked against comoving snapshots of the flagship I N-body simulation at z = (0.9, 1.2, 1.5, 1.8), which have been populated with Hα galaxies leading to catalogues of millions of objects within a volume of about 58 h−3 Gpc3. Our analysis suggests that both models can be used to provide a robust inference of the parameters (h, ωc) in the redshift range under consideration, with comparable constraining power. We additionally determine the range of validity of the EFTofLSS model in terms of scale cuts and model degrees of freedom. From these tests, it emerges that the standard third-order Eulerian bias expansion – which includes local and non-local bias parameters, a matter counter term, and a correction to the shot-noise contribution – can accurately describe the full shape of the real-space galaxy power spectrum up to the maximum wavenumber of kmax = 0.45 hMpc−1, and with a measurement precision of well below the percentage level. Fixing either of the tidal bias parameters to physically motivated relations still leads to unbiased cosmological constraints, and helps in reducing the severity of projection effects due to the large dimensionality of the model. We finally show how we repeated our analysis assuming a volume that matches the expected footprint of Euclid, but without considering observational effects, such as purity and completeness, showing that we can get constraints on the combination (h, ωc) that are consistent with the fiducial values to better than the 68% confidence interval over this range of scales and redshifts.
AB - We investigate the accuracy of the perturbative galaxy bias expansion in view of the forthcoming analysis of the Euclid spectroscopic galaxy samples. We compare the performance of a Eulerian galaxy bias expansion using state-of-the-art prescriptions from the effective field theory of large-scale structure (EFTofLSS) with a hybrid approach based on Lagrangian perturbation theory and high-resolution simulations. These models are benchmarked against comoving snapshots of the flagship I N-body simulation at z = (0.9, 1.2, 1.5, 1.8), which have been populated with Hα galaxies leading to catalogues of millions of objects within a volume of about 58 h−3 Gpc3. Our analysis suggests that both models can be used to provide a robust inference of the parameters (h, ωc) in the redshift range under consideration, with comparable constraining power. We additionally determine the range of validity of the EFTofLSS model in terms of scale cuts and model degrees of freedom. From these tests, it emerges that the standard third-order Eulerian bias expansion – which includes local and non-local bias parameters, a matter counter term, and a correction to the shot-noise contribution – can accurately describe the full shape of the real-space galaxy power spectrum up to the maximum wavenumber of kmax = 0.45 hMpc−1, and with a measurement precision of well below the percentage level. Fixing either of the tidal bias parameters to physically motivated relations still leads to unbiased cosmological constraints, and helps in reducing the severity of projection effects due to the large dimensionality of the model. We finally show how we repeated our analysis assuming a volume that matches the expected footprint of Euclid, but without considering observational effects, such as purity and completeness, showing that we can get constraints on the combination (h, ωc) that are consistent with the fiducial values to better than the 68% confidence interval over this range of scales and redshifts.
KW - cosmological parameters
KW - cosmology: theory
KW - large-scale structure of Universe
UR - https://www.scopus.com/pages/publications/85199443155
U2 - 10.1051/0004-6361/202348939
DO - 10.1051/0004-6361/202348939
M3 - Article
AN - SCOPUS:85199443155
SN - 0004-6361
VL - 687
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - A216
ER -