Inference of the linear matter power spectrum at z = 0 using DESI DR1 Full-Shape data
Measurements of galaxy distributions at large cosmic distances capture clustering from the past. In this study, we use a cosmological model to translate these observations into the present-day galaxy distribution. Specifically, we reconstruct the 3D linear matter power spectrum at redshift z = 0 usi...
| Autores: | , , , , , , , , , , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2026 |
| País: | España |
| Recursos: | Universitat Politècnica de Catalunya (UPC) |
| Repositório: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglês |
| OAI Identifier: | oai:dnet:upcommonspor::0020dc4a5d5df4183427ababbf4db756 |
| Acesso em linha: | https://hdl.handle.net/2117/461974 https://dx.doi.org/10.1088/1475-7516/2026/04/080 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Galaxy clustering Power spectrum Redshift surveys Cosmological parameters from LSS Àrees temàtiques de la UPC::Física::Astronomia i astrofísica |
| Resumo: | Measurements of galaxy distributions at large cosmic distances capture clustering from the past. In this study, we use a cosmological model to translate these observations into the present-day galaxy distribution. Specifically, we reconstruct the 3D linear matter power spectrum at redshift z = 0 using Dark Energy Spectroscopic Instrument (DESI) Year 1 (DR1) galaxy clustering data and Cosmic Microwave Background (CMB) observations, assuming the ¿CDM model, and compare it to the result assuming the w0wa CDM model. Building on previous state-of-the-art methods, we apply Effective Field Theory (EFT) modelling of the galaxy power spectrum to account for small-scale effects in the 2-point statistics of galaxy data. Implementation of the EFT approach improves the modelling of the galaxy power spectrum, providing a more robust consistency test of the assumed cosmological model. By casting both CMB and galaxy clustering observations, spanning distinct redshift regimes, into k-space, we can identify discrepancies between the datasets of different redshifts, which would indicate potential inaccuracies in the assumed expansion history. While previous studies have shown consistency with ¿CDM, this work extends the analysis with higher-quality data to further test the expansion histories of both ¿CDM and w0wa CDM. Our findings show that both ¿CDM and w0wa CDM provide consistent fits to the linear matter power spectrum recovered from DESI DR1 data. |
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