학술논문
Fundamental physics with ESPRESSO: a new determination of the D/H ratio towards PKS1937-101
Document Type
Working Paper
Author
Guarneri, Francesco; Pasquini, Luca; D'Odorico, Valentina; Cristiani, Stefano; Cupani, Guido; Di Marcantonio, Paolo; Hernández, J. I. González; Martins, C. J. A. P.; Mascareño, Alejandro Suárez; Milaković, Dinko; Molaro, Paolo; Murphy, Michael T.; Nunes, Nelson J.; Palle, Enric; Pepe, Francesco; Rebolo, Rafael; Santos, Nuno C.; Santos, Ricardo Génova; Schmidt, Tobias M.; Sousa, Sérgio G.; Sozzetti, Alessandro; Trost, Andrea
Source
Subject
Language
Abstract
Primordial abundances of light elements are sensitive to the physics of the early Universe and can directly constrain cosmological quantities, such as the baryon-to-photon ratio $\eta_{10}$, the baryon density and the number of neutrino families. Deuterium is especially suited for these studies: its primordial abundance is sensitive and monotonically dependent on $\eta_{10}$, allowing an independent measurement of the cosmic baryon density that can be compared, for instance, against the Planck satellite data. The primordial deuterium abundance can be measured in high $H_I$ column density absorption systems towards distant quasars. We report here a new measurement, based on high-resolution ESPRESSO data, of the primordial $D_I$ abundance of a system at redshift $z \sim 3.572$, towards PKS1937-101. Using only ESPRESSO data, we find a D/H ratio of $2.638\pm0.128 \times 10^{-5}$, while including the available UVES data improves the precision, leading to a ratio of $2.608 \pm 0.102 \times 10^{-5}$. The results of this analysis agree with those of the most precise existing measurements. We find that the relatively low column density of this system ($\log{N_{\rm H_I}/ {\rm cm}^{-2}}\sim18 $) introduces modelling uncertainties, which become the main contributor to the error budget.
Comment: Accepted for publication in MNRAS. 16 pages, 10 figures and 6 tables (4 in main text, 2 in Appendix). Full model is available at the end of the manuscript
Comment: Accepted for publication in MNRAS. 16 pages, 10 figures and 6 tables (4 in main text, 2 in Appendix). Full model is available at the end of the manuscript