DESI DR1 Lyα 1D power spectrum: the Fast Fourier Transform estimator measurement

Ravoux, Corentin; Abdul-Karim, Marie-Lynn; Le Goff, Jean-Marc; Armengaud, Eric; Aguilar, Jessica N.; Ahlen, Steven; Bailey, Stephen; Bianchi, Davide; Brodzeller, Allyson; Brooks, David; Chaves-Montero, Jonás; Claybaugh, Todd; Cuceu, Andrei; de Belsunce, Roger; de la Macorra, Axel; Dey, Arjun; Ding, Zhejie; Doel, Peter; Ferraro, Simone; Font-Ribera, Andreu; Forero-Romero, Jaime E.; Gaztañaga, Enrique; Karaçaylı, Naim Göksel; Gontcho, Satya Gontcho A.; Gutierrez, Gaston; Guy, Julien; Herrera-Alcantar, Hiram K.; Ishak, Mustapha; Kehoe, Robert; Kirkby, David; Kisner, Theodore; Kremin, Anthony; Landriau, Martin; Le Guillou, Laurent; Levi, Michael E.; Manera, Marc; Martini, Paul; Meisner, Aaron; Miquel, Ramon; Montero-Camacho, Paulo; Muñoz-Gutiérrez, Andrea; Nadathur, Seshadri; Niz, Gustavo; Palanque-Delabrouille, Nathalie; Pan, Zhiwei; Percival, Will J.; Pérez-Ràfols, Ignasi; Pieri, Matthew M.; Prada, Francisco; Rossi, Graziano; Sanchez, Eusebio; Saulder, Christoph; Schlegel, David; Schubnell, Michael; Seo, Hee-Jong; Silber, Joseph H.; Siudek, Małgorzata; Sprayberry, David; Tan, Ting; Tang, Ji-Jia; Tarlé, Gregory; Walther, Michael; Weaver, Benjamin A.; Yèche, Christophe; Yu, Jiaxi; Zhou, Rongpu; Zou, Hu
Bibliographical reference

Journal of Cosmology and Astroparticle Physics

Advertised on:
11
2025
Number of authors
67
IAC number of authors
1
Citations
0
Refereed citations
0
Description
We present the one-dimensional Lyman-α forest power spectrum measurement derived from the data release 1 (DR1) of the Dark Energy Spectroscopic Instrument (DESI). The measurement of the Lyman-α forest power spectrum along the line of sight from high-redshift quasar spectra provides information on the shape of the linear matter power spectrum, neutrino masses, and the properties of dark matter. In this work, we use a Fast Fourier Transform (FFT)-based estimator, which is validated on synthetic data in a companion paper. Compared to the FFT measurement performed on the DESI early data release, we improve the noise characterization with a cross-exposure estimator and test the robustness of our measurement using various data splits. We also refine the estimation of the uncertainties and now present an estimator for the covariance matrix of the measurement. Furthermore, we compare our results to previous high-resolution and eBOSS measurements. In another companion paper, we present the same DR1 measurement using the Quadratic Maximum Likelihood Estimator (QMLE). These two measurements are consistent with each other and constitute the most precise one-dimensional power spectrum measurement to date, while being in good agreement with results from the DESI early data release.