Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improved Laboratory Transition Probabilities for Ce II, Application to
  the Cerium Abundances of the Sun and Five r-process Rich, Metal-Poor Stars,
  and Rare Earth Lab Data   Recent radiative lifetime measurements accurate to +/- 5% using laser-induced
fluorescence (LIF) on 43 even-parity and 15 odd-parity levels of Ce II have
been combined with new branching fractions measured using a Fourier transform
spectrometer (FTS) to determine transition probabilities for 921 lines of Ce
II. This improved laboratory data set has been used to determine a new solar
photospheric Ce abundance, log epsilon = 1.61 +/- 0.01 (sigma = 0.06 from 45
lines), a value in excellent agreement with the recommended meteoritic
abundance, log epsilon = 1.61 +/- 0.02. Revised Ce abundances have also been
derived for the r-process-rich metal-poor giant stars BD+17 3248, CS 22892-052,
CS 31082-001, HD 115444 and HD 221170. Between 26 and 40 lines were used for
determining the Ce abundance in these five stars, yielding a small statistical
uncertainty of 0.01 dex similar to the Solar result. The relative abundances in
the metal-poor stars of Ce and Eu, a nearly pure r-process element in the Sun,
matches r-process only model predictions for Solar System material. This
consistent match with small scatter over a wide range of stellar metallicities
lends support to these predictions of elemental fractions. A companion paper
includes an interpretation of these new precision abundance results for Ce as
well as new abundance results and interpretations for Pr, Dy and Tm.

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The categories of this paper are: econ
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: math
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The categories of this paper are: nlin
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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: hep-ph