Planets Around Solar Twins/Analogs (PASTA) II: chemical abundances, systematic offsets, and clues to planet formation
arXiv:2508.06976 · doi:10.1051/0004-6361/202556272
Abstract
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 inhomogeneous samples and a lack of direct comparison with stars known to host planets. Aims. We aim to perform a homogeneous and precise abundance analysis of solar twins and analogs that host planets, to investigate possible chemical signatures associated with planet formation. Methods. We obtain high-resolution, high signal-to-noise ratio Magellan/MIKE spectra for 25 solar-like stars, including 22 confirmed or candidate planet hosts and three comparison stars. Stellar parameters and elemental abundances for 23 elements (from C to Eu) are derived through a strict line-by-line differential analysis relative to the Sun. Results. Our sample spans [Fe/H] = -0.23 to +0.18 dex and includes 20 solar analogs, six of which are solar twins. Typical abundance uncertainties range from 0.01 to 0.05 dex for lighter elements (e.g., Fe, Si, C, O, Na) and up to 0.1 dex for neutron-capture elements. The Sun is consistently depleted in refractory elements relative to all solar analogs and twins, regardless of planet type. Stars hosting small planets tentatively show slightly stronger refractory element depletion than those hosting giant planets, though the difference is not yet statistically significant. Conclusions. We emphasize the need for strictly differential, line-by-line analyses relative to the Sun, as well as careful consideration of systematic differences between instruments, to ensure consistency and the homogeneity required to achieve our goals.
Main text has 9 pages, 3 figures, 4 tables; accepted for publication in A&A
References in corpus (18)
- A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
- High-precision abundances of elements in solar twin stars: Trends with stellar age and elemental condensation temperature
- Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program II: Cu, Zn, Sr, Y, Zr, Ba, Ce, Nd and Eu
- Oxygen Abundances in Nearby Stars. Clues to the formation and evolution of the Galactic disk
- The Solar Twin Planet Search. I. Fundamental parameters of the stellar sample
- WASP-42 b and WASP-49 b: two new transiting sub-Jupiters
- 18 Sco: a solar twin rich in refractory and neutron-capture elements. Implications for chemical tagging
- High eccentricity planets from the Anglo-Australian Planet Search
- 3-D selection of 167 sub-stellar companions to nearby stars
- High-precision abundances of Sc, Mn, Cu, and Ba in solar twins. Trends of element ratios with stellar age
- Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program IV. Carbon and C/O ratios for Galactic stellar populations and planet hosts
- Fingerprints of giant planets in the composition of solar twins
- TESS Delivers Five New Hot Giant Planets Orbiting Bright Stars from the Full Frame Images
- TESS Reveals a Short-period Sub-Neptune Sibling (HD 86226c) to a Known Long-period Giant Planet
- WIYN Open Cluster Study: The Old Open Cluster, NGC 188, and a Re-evaluation of Lithium-Richness Among Red Giants
- WIYN Open Cluster Study LXXIX. M48 (NGC 2548) I. Radial Velocities, Rotational Velocities, and Metallicities of Stars in the Open Cluster M48 (NGC 2548)
- Statistics of the Chemical Composition of Solar Analog Stars and Links to Planet Formation
- Multi techniques approach to identify and/or constrain radial velocity sub-stellar companions