TY - JOUR
T1 - Euclid preparation XIX. Impact of magnification on photometric galaxy clustering
AU - Lepori, F.
AU - Tutusaus, I.
AU - Viglione, C.
AU - Bonvin, C.
AU - Camera, S.
AU - Castander, F. J.
AU - Durrer, R.
AU - Fosalba, P.
AU - Jelic-Cizmek, G.
AU - Kunz, M.
AU - Adamek, J.
AU - Casas, S.
AU - Martinelli, M.
AU - Sakr, Z.
AU - Sapone, D.
AU - Amara, A.
AU - Auricchio, N.
AU - Bodendorf, C.
AU - Bonino, D.
AU - Branchini, E.
AU - Brescia, M.
AU - Brinchmann, J.
AU - Capobianco, V.
AU - Carbone, C.
AU - Carretero, J.
AU - Castellano, M.
AU - Cavuoti, S.
AU - Cimatti, A.
AU - Cledassou, R.
AU - Congedo, G.
AU - Conselice, C. J.
AU - Conversi, L.
AU - Copin, Y.
AU - Corcione, L.
AU - Courbin, F.
AU - Da Silva, A.
AU - Degaudenzi, H.
AU - Douspis, M.
AU - Dubath, F.
AU - Dupac, X.
AU - Dusini, S.
AU - Ealet, A.
AU - Farrens, S.
AU - Ferriol, S.
AU - Niemi, S. M.
AU - Schneider, P.
AU - Starck, J. L.
AU - Wang, Y.
AU - Gozaliasl, G.
AU - Sánchez, A. G.
AU - Euclid Collaboration
N1 - Funding Information:
Acknowledgements. C.B., R.D., G.J., M.K., J.A. and F.L. acknowledge support from the Swiss National Science Foundation. C.B. acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 863929; project title “Testing the law of gravity with novel large-scale structure observables”). I.T. acknowledges support from the Spanish Ministry of Science, Innovation and Universities through grant ESP2017-89838, and the H2020 programme of the European Commission through grant 776247. S.C. acknowledges support from the ‘Departments of Excellence 2018-2022’ Grant (L. 232/2016) awarded by the Italian Ministry of University and Research (Mur). The Euclid Consortium acknowledges the European Space Agency and a number of agencies and institutes that have supported the development of Euclid, in particular the Academy of Finland, the Agenzia Spaziale Italiana, the Belgian Science Policy, the Canadian Euclid Consortium, the French Centre National d’Etudes Spatiales, the Deutsches Zentrum für Luft-und Raumfahrt, the Danish Space Research Institute, the Fundação para a Ciência e a Tecnologia, the Ministerio de Econo-mia y Competitividad, the National Aeronautics and Space Administration, the National Astronomical Observatory of Japan, the Netherlandse Onderzoekschool Voor Astronomie, the Norwegian Space Agency, the Romanian Space Agency, the State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space Office (SSO), and the United Kingdom Space Agency. A complete and detailed list is available on the Euclid web site (http://www.euclid-ec.org).
Publisher Copyright:
c ESO 2022
PY - 2022/6/1
Y1 - 2022/6/1
N2 - Aims. We investigate the importance of lensing magnification for estimates of galaxy clustering and its cross-correlation with shear for the photometric sample of Euclid. Using updated specifications, we study the impact of lensing magnification on the constraints and the shift in the estimation of the best fitting cosmological parameters that we expect if this effect is neglected. Methods. We follow the prescriptions of the official Euclid Fisher matrix forecast for the photometric galaxy clustering analysis and the combination of photometric clustering and cosmic shear. The slope of the luminosity function (local count slope), which regulates the amplitude of the lensing magnification, and the galaxy bias have been estimated from the Euclid Flagship simulation. Results. We find that magnification significantly affects both the best-fit estimation of cosmological parameters and the constraints in the galaxy clustering analysis of the photometric sample. In particular, including magnification in the analysis reduces the 1σ errors on Ωm,0, w0, wa at the level of 20–35%, depending on how well we will be able to independently measure the local count slope. In addition, we find that neglecting magnification in the clustering analysis leads to shifts of up to 1.6σ in the best-fit parameters. In the joint analysis of galaxy clustering, cosmic shear, and galaxy–galaxy lensing, magnification does not improve precision, but it leads to an up to 6σ bias if neglected. Therefore, for all models considered in this work, magnification has to be included in the analysis of galaxy clustering and its cross-correlation with the shear signal (3 × 2pt analysis) for an accurate parameter estimation.
AB - Aims. We investigate the importance of lensing magnification for estimates of galaxy clustering and its cross-correlation with shear for the photometric sample of Euclid. Using updated specifications, we study the impact of lensing magnification on the constraints and the shift in the estimation of the best fitting cosmological parameters that we expect if this effect is neglected. Methods. We follow the prescriptions of the official Euclid Fisher matrix forecast for the photometric galaxy clustering analysis and the combination of photometric clustering and cosmic shear. The slope of the luminosity function (local count slope), which regulates the amplitude of the lensing magnification, and the galaxy bias have been estimated from the Euclid Flagship simulation. Results. We find that magnification significantly affects both the best-fit estimation of cosmological parameters and the constraints in the galaxy clustering analysis of the photometric sample. In particular, including magnification in the analysis reduces the 1σ errors on Ωm,0, w0, wa at the level of 20–35%, depending on how well we will be able to independently measure the local count slope. In addition, we find that neglecting magnification in the clustering analysis leads to shifts of up to 1.6σ in the best-fit parameters. In the joint analysis of galaxy clustering, cosmic shear, and galaxy–galaxy lensing, magnification does not improve precision, but it leads to an up to 6σ bias if neglected. Therefore, for all models considered in this work, magnification has to be included in the analysis of galaxy clustering and its cross-correlation with the shear signal (3 × 2pt analysis) for an accurate parameter estimation.
KW - cosmological parameters
KW - cosmology: theory
KW - large-scale structure of Universe
UR - http://www.scopus.com/inward/record.url?scp=85134043401&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/202142419
DO - 10.1051/0004-6361/202142419
M3 - Article
AN - SCOPUS:85134043401
SN - 0004-6361
VL - 662
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - A93
ER -