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We have conducted a differential elemental abundance analysis of unprecedented accuracy (0.01 dex) of the Sun relative to 11 solar twins from the Hipparcos catalogue and 10 solar analogs from planet searches. We find that the Sun shows a…

Solar and Stellar Astrophysics · Physics 2014-11-20 Jorge Melendez , Martin Asplund , Bengt Gustafsson , David Yong

Highly-differential spectroscopic studies have revealed that the Sun is deficient in refractory elements relative to solar twins. To investigate the role of giant planets on this signature, we present a high precision abundance analysis of…

Solar and Stellar Astrophysics · Physics 2025-08-13 M. Carlos , A. M. Amarsi , P. E. Nissen , G. Canocchi

For more than 140 years the chemical composition of our Sun has been considered typical of solar-type stars. Our highly differential elemental abundance analysis of unprecedented accuracy (~0.01 dex) of the Sun relative to solar twins,…

Earth and Planetary Astrophysics · Physics 2015-05-14 J. Melendez , M. Asplund , B. Gustafsson , D. Yong , I. Ramirez

Context. Previous studies have suggested that the Sun is relatively depleted in refractory elements compared to other solar twins or analogs, potentially as a result of planet formation. However, such conclusions are often limited by…

Earth and Planetary Astrophysics · Physics 2025-09-10 Qinghui Sun , Chenyang Ji , Sharon Xuesong Wang , Zitao Lin , Johanna Teske , Yuan-Sen Ting , Megan Bedell , Fan Liu

The compositions of stars are a critical diagnostic tool for many topics in astronomy such as the evolution of our Galaxy, the formation of planets, and the uniqueness of the Sun. Previous spectroscopic measurements indicate a large…

Implications of the recently discovered systematic abundance difference between the Sun and two collections of `solar twins' are discussed. The differences can be understood as an imprint on the abundances of the solar convection zone…

Solar and Stellar Astrophysics · Physics 2009-08-26 A. Nordlund

Sun-like stars are a new probe of variations in the fine-structure constant, $\alpha$, via the solar twins approach: velocity separations of close pairs of absorption lines are compared between stars with very similar stellar parameters,…

Solar and Stellar Astrophysics · Physics 2023-01-04 Daniel A. Berke , Michael T. Murphy , Chris Flynn , Fan Liu

Magnetic features on the surfaces of cool stars cause variations of their brightness. Such variations have been extensively studied for the Sun. Recent planet-hunting space telescopes allowed measuring brightness variations in hundred…

Solar and Stellar Astrophysics · Physics 2020-04-15 N. -E. Nèmec , A. I. Shapiro , N. A. Krivova , S. K. Solanki , R. V. Tagirov , R. H. Cameron , S. Dreizler

We are carrying out a search for planets around a sample of solar twin stars using the HARPS spectrograph. The goal of this project is to exploit the advantage offered by solar twins to obtain chemical abundances of unmatched precision.…

Solar and Stellar Astrophysics · Physics 2014-12-03 I. Ramirez , J. Melendez , J. Bean , M. Asplund , M. Bedell , T. Monroe , L. Casagrande , L. Schirbel , S. Dreizler , J. Teske , M. Tucci Maia , A. Alves-Brito , P. Baumann

The rich absorption spectra of Sun-like stars are enticing probes for variations in the fine-structure constant, $\alpha$, which gauges the strength of electromagnetism. While individual line wavelengths are sensitive to $\alpha$, they are…

Solar and Stellar Astrophysics · Physics 2023-01-04 Daniel A. Berke , Michael T. Murphy , Chris Flynn , Fan Liu

The Sun provides a standard reference against which we compare the chemical abundances found anywhere else in the Universe. Nevertheless, there is not a unique 'solar' composition, since the chemical abundances found in the solar interior,…

Solar and Stellar Astrophysics · Physics 2021-06-22 Carlos Allende Prieto

The Sun is used as the fundamental standard in chemical abundance studies, thus it is important to know whether the solar abundance pattern is representative of the solar neighborhood. Albeit at low precision (0.05 - 0.10 dex) the Sun seems…

Solar and Stellar Astrophysics · Physics 2015-06-16 Jorge Melendez

Recent studies have shown that the elemental abundances in the Sun are anomalous when compared to most (about 85%) nearby solar twin stars. Compared to its twins, the Sun exhibits a deficiency of refractory elements (those with condensation…

Solar and Stellar Astrophysics · Physics 2015-05-19 I. Ramirez , M. Asplund , P. Baumann , J. Melendez , T. Bensby

We derive the abundance of 19 elements in a sample of 64 stars with fundamental parameters very similar to solar, which minimizes the impact of systematic errors in our spectroscopic 1D-LTE differential analysis, using high-resolution…

Solar and Stellar Astrophysics · Physics 2009-12-10 I. Ramirez , J. Melendez , M. Asplund

Context: Studies based on high-precision abundance determinations revealed that chemical patterns of solar twins are characterised by the correlation between the differential abundances relative to the Sun and the condensation temperatures…

Solar and Stellar Astrophysics · Physics 2016-01-20 Lorenzo Spina , Jorge Meléndez , Ivan Ramírez

The solar chemical composition is a fundamental yardstick in astrophysics and the topic of heated debate in recent literature. We re-evaluate the abundance of sulphur in the photosphere by studying seven S I lines in the solar disc-centre…

Solar and Stellar Astrophysics · Physics 2025-11-05 A. M. Amarsi , W. Li , N. Grevesse , A. J. G. Jurewicz

Elemental abundance studies of solar twin stars suggest that the solar chemical composition contains signatures of the formation of terrestrial planets in the solar system, namely small but significant depletions of the refractory elements.…

Solar and Stellar Astrophysics · Physics 2015-06-17 I. Ramirez , J. Melendez , M. Asplund

Regular spaceborne measurements have revealed that solar brightness varies on multiple timescales, variations on timescales greater than a day being attributed to surface magnetic field. Independently, ground-based and spaceborne…

Solar and Stellar Astrophysics · Physics 2016-04-27 A. I. Shapiro , S. K. Solanki , N. A. Krivova , K. L. Yeo , W. K. Schmutz

We present high-resolution spectroscopic observations of the \ion{Li}{1} resonance line in a sample of 62 stars that belong to 31 common-proper motion pairs with twin F or G-type components. Photospheric abundances of lithium were derived…

Astrophysics · Physics 2009-11-07 Eduardo L. Martin , Gibor Basri , Yakiv Pavlenko , Yuri Lyubchik
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