{"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/the-triply-ionized-carbon-forest-from-eboss","title":"The triply-ionized carbon forest from eBOSS: cosmological correlations with quasars in SDSS-IV DR14","arxiv_id":"1801.01852","date":"2018-01-05","proceeding":null,"authors":["Michael Blomqvist","Matthew M. Pieri","Hélion du Mas des Bourboux","Nicolás G. Busca","Anže Slosar","Julian E. Bautista","Jonathan Brinkmann","Joel R. Brownstein","Kyle Dawson","Victoria de Sainte Agathe","Julien Guy","Will J. Percival","Ignasi Pérez-Ràfols","James Rich","Donald P. Schneider"],"abstract":"We present measurements of the cross-correlation of the triply-ionized carbon (CIV) forest with quasars using Sloan Digital Sky Survey Data Release 14. The study exploits a large sample of new quasars from the first two years of observations by the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). The CIV forest is a weaker tracer of large-scale structure than the Ly$\\alpha$ forest, but benefits from being accessible at redshifts $z<2$ where the quasar number density from eBOSS is high. Our data sample consists of 287,651 CIV forest quasars in the redshift range $1.4<z<3.5$ and 387,315 tracer quasars with $1.2<z<3.5$. We measure large-scale correlations from CIV absorption occuring in three distinct quasar rest-frame wavelength bands of the spectra referred to as the CIV forest, the SiIV forest and the Ly$\\alpha$ forest. From the combined fit to the quasar-CIV cross-correlations for the CIV forest and the SiIV forest, the CIV redshift-space distortion parameter is $\\beta_{\\rm CIV}=0.27_{\\ -0.14}^{\\ +0.16}$ and its combination with the CIV linear transmission bias parameter is $b_{\\rm CIV}(1+\\beta_{\\rm CIV})=-0.0183_{\\ -0.0014}^{\\ +0.0013}$ ($1\\sigma$ statistical error) at the mean redshift $z=2.00$. Splitting the sample at $z=2.2$ to constrain the bias evolution with redshift yields the power-law exponent $\\gamma=0.60\\pm0.63$, indicating a significantly weaker redshift-evolution than for the Ly$\\alpha$ forest linear transmission bias. We demonstrate that CIV absorption has the potential to be used as a probe of baryon acoustic oscillations (BAO). While the current data set is insufficient for a detection of the BAO peak feature, the final quasar samples for redshifts $1.4<z<2.2$ from eBOSS and the Dark Energy Spectroscopic Instrument (DESI) are expected to provide measurements of the isotropic BAO scale to $\\sim7\\%$ and $\\sim3\\%$ precision, respectively, at $z\\simeq1.6$.","url_abs":"http://arxiv.org/abs/1801.01852v2","url_pdf":"http://arxiv.org/pdf/1801.01852v2.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":"the-triply-ionized-carbon-forest-from-eboss","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}