{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/baryon-acoustic-oscillations-from-the-cross","title":"Baryon acoustic oscillations from the cross-correlation of Ly$\\alpha$ absorption and quasars in eBOSS DR14","arxiv_id":"1904.03430","date":"2019-04-06","proceeding":null,"authors":["Michael Blomqvist","Hélion du Mas des Bourboux","Nicolás G. Busca","Victoria de Sainte Agathe","James Rich","Christophe Balland","Julian E. Bautista","Kyle Dawson","Andreu Font-Ribera","Julien Guy","Jean-Marc Le Goff","Nathalie Palanque-Delabrouille","Will J. Percival","Ignasi Pérez-Ràfols","Matthew M. Pieri","Donald P. Schneider","Anže Slosar","Christophe Yèche"],"abstract":"We present a measurement of the baryon acoustic oscillation (BAO) scale at redshift $z=2.35$ from the three-dimensional correlation of Lyman-$\\alpha$ (Ly$\\alpha$) forest absorption and quasars. The study uses 266,590 quasars in the redshift range $1.77<z<3.5$ from the Sloan Digital Sky Survey (SDSS) Data Release 14 (DR14). The sample includes the first two years of observations by the SDSS-IV extended Baryon Oscillation Spectroscopic Survey (eBOSS), providing new quasars and re-observations of BOSS quasars for improved statistical precision. Statistics are further improved by including Ly$\\alpha$ absorption occurring in the Ly$\\beta$ wavelength band of the spectra. From the measured BAO peak position along and across the line of sight, we determined the Hubble distance $D_{H}$ and the comoving angular diameter distance $D_{M}$ relative to the sound horizon at the drag epoch $r_{d}$: $D_{H}(z=2.35)/r_{d}=9.20\\pm 0.36$ and $D_{M}(z=2.35)/r_{d}=36.3\\pm 1.8$. These results are consistent at $1.5\\sigma$ with the prediction of the best-fit spatially-flat cosmological model with the cosmological constant reported for the Planck (2016) analysis of cosmic microwave background anisotropies. Combined with the Ly$\\alpha$ auto-correlation measurement presented in a companion paper, the BAO measurements at $z=2.34$ are within $1.7\\sigma$ of the predictions of this model.","url_abs":"http://arxiv.org/abs/1904.03430v3","url_pdf":"http://arxiv.org/pdf/1904.03430v3.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"baryon-acoustic-oscillations-from-the-cross","repo_url":"https://github.com/igmhub/picca","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}