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Related papers: Light element evolution resulting from WMAP data

200 papers

This is a report on some highlights of some research on the rare light elements, lithium (Li), beryllium (Be), and boron (B), that I presented in my Henry Norris Russell Lecture in January, 2020. It is not a comprehensive review of work on…

Solar and Stellar Astrophysics · Physics 2023-02-01 Ann Merchant Boesgaard

We have recently considered cosmologies in which the Universal scale factor varies as a power of the age of the Universe and concluded that they cannot satisfy the observational constraints on the present age, the magnitude-redshift…

Astrophysics · Physics 2009-10-31 M. Kaplinghat , G. Steigman , T. P. Walker

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite…

Astrophysics · Physics 2009-11-11 Ann Merchant Boesgaard , Megan C. Novicki , Alex Stephens

Population III stars supplied the first light and metals in the Universe, setting the pace of re-ionisation and early chemical enrichment. In dense haloes their evolution can be strongly influenced by the energy released when WIMPs…

Solar and Stellar Astrophysics · Physics 2026-01-21 Anais Pauchet , Devesh Nandal

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster

We study big bang nucleosynthesis in the presence of large mass-scale, non-linear entropy fluctuations. Overdense regions, with masses above the local baryon-Jeans mass, are expected to collapse and form condensed objects. Surviving…

Astrophysics · Physics 2009-10-22 K. Jedamzik , G. M. Fuller

One of the still viable candidates for the dark matter is the so-called mirror matter. Its cosmological and astrophysical implications were widely studied in many aspects, pointing out the importance to go further with research and refine…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-14 Paolo Ciarcelluti

Our aim is to measure accurate, homogeneous neutron-capture element abundances for the sample of 32 EMP giant stars studied earlier in this series, including 22 stars with [Fe/H] $< -$3.0. Based on high-resolution, high S/N spectra from the…

In this paper we study the very early phases of the evolution of our Galaxy by means of a chemical evolution model which reproduces most of the observational constraints in the solar vicinity and in the disk. We have restricted our analysis…

Astrophysics · Physics 2016-08-30 Cristina Chiappini , Francesca Matteucci , Timothy Beers , Ken'ichi Nomoto

A long sought after goal using chemical abundance patterns derived from metal-poor stars is to understand the Galactic chemical evolution (GCE) and to pin down the nature of the first stars (Pop III). Here, we use a sample of 14 metal-poor…

Light element ($^6$Li, $^7$Li and $^9$Be) depletion isochrones for halo stars have been calculated with standard stellar evolution models. These models include the latest available opacities and are computed through the sub-giant branch. If…

Astrophysics · Physics 2009-10-22 Brian Chaboyer

Context. Carbon, nitrogen, and oxygen are the most abundant elements throughout the universe, after hydrogen and helium. Studying these elements in low-metallicity stars can provide crucial information on the chemical composition in the…

Combined with other CMB experiments, the WMAP survey provides an accurate estimate of the baryon density of the Universe. In the framework of the standard Big Bang Nucleosynthesis (BBN), such a baryon density leads to predictions for the…

Astrophysics · Physics 2009-01-19 Julien Larena , Jean-Michel Alimi , Arturo Serna

Lithium abundances in a selected sample of halo stars have been revised by using the new accurate IRFM effective temperatures by Alonso, Arribas & Martinez-Roger (1996a). From 41 plateau stars (Teff > 5700 and [Fe/H] <= -1.5) we found no…

Astrophysics · Physics 2015-06-24 Piercarlo Bonifacio , Paolo Molaro

We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of…

High Energy Physics - Phenomenology · Physics 2015-10-28 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

Accurate 7Li(d,n)24He thermonuclear reaction rates are crucial for precise prediction of the primordial abundances of Lithium and Beryllium and to probe the mysteries beyond fundamental physics and the standard cosmological model. However,…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 S. Q. Hou , T. Kajino , T. C. L. Trueman , M. Pignatari , Y. D. Luo , C. A. Bertulani

In this work, two aspects of the chemical evolution of 4He in the Galaxy are considered on the basis of a sample of disk planetary nebulae (PN). First, an application of corrections owing to the contamination of 4He from the evolution of…

Astrophysics · Physics 2009-10-31 W. J. Maciel

The discovery of the Spite plateau in the abundances of 7Li for metal-poor stars led to the determination of an observationally deduced primordial lithium abundance. However, after the success of the Wilkinson Microwave Anisotropy Probe…

Astrophysics · Physics 2009-11-13 A. Hosford , S. G. Ryan , A. E. Garcia Perez , J. E. Norris , K. A. Olive

We update Standard Big Bang Nucleosynthesis (SBBN) calculations on the basis of recent nuclear physics compilations (NACRE in particular), experimental and theoretical works. By a Monte--Carlo technique, we calculate the uncertainties on…

Astrophysics · Physics 2009-11-07 Alain Coc , Elisabeth Vangioni-Flam , Michel Cass'e , Marc Rabiet

Elemental abundance ratios as tracers of stellar populations are discussed with emphasis on F, G, and K stars providing a `fossil' record of the chemical evolution of the Galaxy. Most abundance studies have been based on homogeneous 1D…

Astrophysics of Galaxies · Physics 2011-09-20 Poul Erik Nissen