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Related papers: Abundances in the Uranium-Rich Star CS 31082-001

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We obtain age estimates for the progenitor(s) of the extremely metal-poor ([Fe/H = -2.9) halo star CS 31082-001, based on the recently reported first observation of a Uranium abundance in this (or any other) star. Age estimates are derived…

Astrophysics · Physics 2008-11-26 R. Toenjes , H. Schatz , K. -L. Kratz , B. Pfeiffer , T. C. Beers , J. Cowan , V. Hill

The discovery of the second highly $r$-process-enhanced, extremely metal-poor star, CS 31082-001 ([Fe/H] $= -2.9$) has provided a powerful new tool for age determination, by virtue of the detection and measurement of the radioactive species…

Astrophysics · Physics 2009-11-07 Shinya Wanajo , Naoki Itoh , Yuhri Ishimaru , Satoshi Nozawa , Timothy C. Beers

We revisit the abundances of neutron-capture elements in the metal-poor ([Fe/H]=-2.9) r-process-rich halo star CS 31082-001. Partly motivated by the development of the new near-ultraviolet Cassegrain U-band Efficient Spectrograph for the…

Solar and Stellar Astrophysics · Physics 2023-07-03 H. Ernandes , M. J. Castro , B. Barbuy , M. Spite , V. Hill , B. Castilho , C. J. Evans

We present a high-resolution spectroscopic analysis of the bright (V=11.7), extreme halo giant CS31082-001 ([Fe/H] = -2.9), obtained in an ESO-VLT Large Programme dedicated to very metal-poor stars. We find CS31082-001 to be extremely rich…

The 'First Stars' programme revealed the metal-poor halo star CS 31082-001 to be r-process and actinide rich, including the first measurement of a uranium abundance for an old star. To better characterise and understand such rare objects,…

Solar and Stellar Astrophysics · Physics 2022-02-10 H. Ernandes , B. Barbuy , A. Friaça , V. Hill , 2 M. Spite , F. Spite , B. V. Castilho , C. J. Evans

Detailed abundances of the elements produced by r-process nucleosynthesis in various circumstances are our best observational clues to their origin, since the site(s) of r-element production is(are) still not known with certainty. A small…

The very-metal-poor halo star CS31082-001 was discovered to be very strongly r-process-enhanced during the course of a VLT+UVES high-resolution follow-up of metal-poor stars identified in the HK survey of Beers and colleagues. Both the…

Astrophysics · Physics 2007-05-23 V. Hill , B. Plez , R. Cayrel , T. C. Beers

The CH star CS 31062-050 ([Fe/H]=-2.42) is one of the most useful stars yet discovered for evaluating the s-process in metal-poor stars. It is very abundant in heavy elements (e.g., [La/Fe]=2.2), and its relatively cool temperature and low…

Astrophysics · Physics 2009-11-10 Jennifer A. Johnson , Michael Bolte

It is argued that the abundances of r-process related elements in stars with -3<[Fe/H]<-1 can be explained by the contributions of three sources. The sources are: the first generations of very massive (>100 solar masses) stars that are…

Astrophysics · Physics 2009-11-06 Y. -Z. Qian , G. J. Wasserburg

We present detailed chemical abundances of three new bright (V ~ 11), extremely metal-poor ([Fe/H] ~ -3.0), r-process-enhanced halo red giants based on high-resolution, high-S/N Magellan/MIKE spectra. We measured abundances for 20-25…

First results are reported of a new abundance study of neutron-capture elements in the ultra-metal-poor (UMP; [Fe/H] = -3.1) halo field giant star CS 22892-052. Using new high resolution, high signal-to-noise spectra, abundances of more…

We measured new abundances of so-called light neutron-capture of first peak elements using local thermodynamic equilibrium (LTE) 1D analysis; this analysis resulted in a sample of 11 very metal-poor stars, from [Fe/H]=-2.5 to [Fe/H]=-3.4,…

Solar and Stellar Astrophysics · Physics 2018-04-04 François Spite , Monique Spite , Beatriz Barbuy , Piercarlo Bonifacio , Elisabetta Caffau , Patrick François

The productions of thorium and uranium are key ingredients in $r$-process nucleo-cosmochronology. With the combination of improved nuclear and stellar data, we have made detailed investigations on the $r$-process abundance pattern in the…

Nuclear Theory · Physics 2010-01-07 Zhongming Niu , Baohua Sun , Jie Meng

High-resolution spectra obtained with three ground-based facilities and the Hubble Space Telescope (HST) have been combined to produce a new abundance analysis of CS 22892-052, an extremely metal-poor giant with large relative enhancements…

In a previous paper we were able to measure the abundance of uranium and thorium in the very-metal poor halo giant BPS CS 31082-001, but only obtained an upper limit for the abundance of lead (Pb). We have got from ESO 17 hours of…

Astrophysics · Physics 2009-11-10 B. Plez , V. Hill , R. Cayrel , M. Spite , B. Barbuy , T. C. Beers , P. Bonifacio , F. Primas , B. Nordström

We report an abundance analysis for the highly r-process-enhanced (r-II) star CS 29497-004, a very metal-poor giant with Teff = 5013K and [Fe/H]=-2.85, whose nature was initially discovered in the course of the HERES project. Our analysis…

Astrophysics of Galaxies · Physics 2017-11-22 V. Hill , N. Christlieb , T. C. Beers , P. S. Barklem , K. -L. Kratz , B. Nordström , B. Pfeiffer , K. Farouqi

Rapid neutron-capture (i.e., r-process) nucleosynthesis calculations, employing internally consistent and physically realistic nuclear physics input (QRPA beta-decay rates and the ETFSI-Q nuclear mass model), have been made. These…

We present quantitative predictions for the abundances of r-process elements in stars formed very early in the Galactic history using a phenomenological two-component r-process model based on the I129 and Hf182 inventory in the early solar…

Astrophysics · Physics 2009-10-31 Y. -Z. Qian , G. J. Wasserburg

During an ESO-VLT large program devoted to high-resolution spectroscopy of extremely metal-poor stars selected from the H&K survey of Beers and colleagues, a [Fe/H] giant star was found to be as enriched in neutron-capture r-process…

Astrophysics · Physics 2007-05-23 R. Cayrel

We present the results of an abundance analysis for a sample of stars with $-4<$[Fe/H]$<-2$. The data were obtained with the HIRES spectrograph at Keck Observatory. The set includes 28 stars, with effective temperature ranging from 4800 to…

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