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arXiv · 2306.06311

The Dark Energy Spectroscopic Instrument: One-dimensional power spectrum from first Lyman-$\alpha$ forest samples with Fast Fourier Transform

Corentin Ravoux·Marie Lynn Abdul-Karim·Eric Armengaud·Michael Walther·Naim Göksel Karaçaylı·Paul Martini·Julien Guy·Jessica Nicole Aguilar·Steven Ahlen·Stephen Bailey·Julian Bautista·Sergio Felipe Beltran·David Brooks·Laura Cabayol-Garcia·Solène Chabanier·Edmond Chaussidon·Jonás Chaves-Montero·Kyle Dawson·Rodrigo de la Cruz·Axel de la Macorra·Peter Doel·Kevin Fanning·Andreu Font-Ribera·Jaime Forero-Romero·Satya Gontcho A Gontcho·Alma Gonzalez-Morales·Calum Gordon·Hiram Herrera-Alcantar·Klaus Honscheid·Vid Iršič·Mustapha Ishak·Robert Kehoe·Theodore Kisner·Anthony Kremin·Martin Landriau·Laurent Le Guillou·Michael Levi·Zarija Lukić·Christophe Magneville·Aaron Meisner·Ramon Miquel·John Moustakas·Eva-Maria Mueller·Andrea Muñoz-Gutiérrez·Lucas Napolitano·Jundan Nie·Gustavo Niz·Nathalie Palanque-Delabrouille·Will Percival·Ignasi Pérez-Ràfols·Matthew Pieri·Claire Poppett·Francisco Prada·César Ramírez Pérez·Graziano Rossi·Eusebio Sanchez·David Schlegel·Michael Schubnell·Hee-Jong Seo·Francesco Sinigaglia·Ting Tan·Gregory Tarlé·Ben Wang·Benjamin Weaver·Christophe Yèche·Zhimin Zhou
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Abstract

We present the one-dimensional Lyman-$\alpha$ forest power spectrum measurement using the first data provided by the Dark Energy Spectroscopic Instrument (DESI). The data sample comprises $26,330$ quasar spectra, at redshift $z > 2.1$, contained in the DESI Early Data Release and the first two months of the main survey. We employ a Fast Fourier Transform (FFT) estimator and compare the resulting power spectrum to an alternative likelihood-based method in a companion paper. We investigate methodological and instrumental contaminants associated to the new DESI instrument, applying techniques similar to previous Sloan Digital Sky Survey (SDSS) measurements. We use synthetic data based on log-normal approximation to validate and correct our measurement. We compare our resulting power spectrum with previous SDSS and high-resolution measurements. With relatively small number statistics, we successfully perform the FFT measurement, which is already competitive in terms of the scale range. At the end of the DESI survey, we expect a five times larger Lyman-$\alpha$ forest sample than SDSS, providing an unprecedented precise one-dimensional power spectrum measurement.

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Corentin Ravoux, Marie Lynn Abdul-Karim, Eric Armengaud, Michael Walther, Naim Göksel Karaçaylı, Paul Martini, Julien Guy, Jessica Nicole Aguilar, Steven Ahlen, Stephen Bailey, Julian Bautista, Sergio Felipe Beltran, David Brooks, Laura Cabayol-Garcia, Solène Chabanier, Edmond Chaussidon, Jonás Chaves-Montero, Kyle Dawson, Rodrigo de la Cruz, Axel de la Macorra, Peter Doel, Kevin Fanning, Andreu Font-Ribera, Jaime Forero-Romero, Satya Gontcho A Gontcho, Alma Gonzalez-Morales, Calum Gordon, Hiram Herrera-Alcantar, Klaus Honscheid, Vid Iršič, Mustapha Ishak, Robert Kehoe, Theodore Kisner, Anthony Kremin, Martin Landriau, Laurent Le Guillou, Michael Levi, Zarija Lukić, Christophe Magneville, Aaron Meisner, Ramon Miquel, John Moustakas, Eva-Maria Mueller, Andrea Muñoz-Gutiérrez, Lucas Napolitano, Jundan Nie, Gustavo Niz, Nathalie Palanque-Delabrouille, Will Percival, Ignasi Pérez-Ràfols, Matthew Pieri, Claire Poppett, Francisco Prada, César Ramírez Pérez, Graziano Rossi, Eusebio Sanchez, David Schlegel, Michael Schubnell, Hee-Jong Seo, Francesco Sinigaglia, Ting Tan, Gregory Tarlé, Ben Wang, Benjamin Weaver, Christophe Yèche, Zhimin Zhou. 2023-06-09. The Dark Energy Spectroscopic Instrument: One-dimensional power spectrum from first Lyman-$\alpha$ forest samples with Fast Fourier Transform. https://doi.org/10.1093/mnras%2Fstad3008

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