English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Solar twins and analogs are fundamental in the characterization of the Sun'splace in the context of stellar measurements, as they are in understanding howtypical the solar properties are in its neighborhood. They are also importantfor representing sunlight observable in the night sky for diverse photometricand spectroscopic tasks, besides being natural candidates for harboringplanetary systems similar to ours and possibly even life-bearing environments.We report a photometric and spectroscopic survey of solar twin stars within 50pc of the Sun. Hipparcos absolute magnitudes and (B-V)_Tycho colors were usedto define a 2 sigma box around the solar values, where 133 stars wereconsidered. Additional stars resembling the solar UBV colors in a broad sense,plus stars present in the lists of Hardorp, were also selected. All objectswere ranked by a color-similarity index with respect to the Sun, defined byuvby and BV photometry. Moderately high-resolution, high-S/N spectra were usedfor a subsample of equatorial-southern stars to derive Teff, log g, and [Fe/H]with average internal errors better than 50 K, 0.20 dex, and 0.08 dex,respectively. Ages and masses were estimated from theoretical HR diagrams. Thecolor-similarity index proved very successful. We identify and rank newexcellent solar analogs, which are fit to represent the Sun in the night sky.Some of them are faint enough to be of interest for moderately largetelescopes. We also identify two stars with near-UV spectra indistinguishablefrom the Sun's. We present five new "probable" solar twin stars, besides fivenew "possible" twins. Masses and ages for the best solar twin candidates lievery close to the solar values, but chromospheric activity levels rangesomewhat. We propose that the solar twins be emphasized in the ongoing searchesfor extra-solar planets and SETI searches.

A photometric and spectroscopic survey of solar twin stars within 50 parsecs of the Sun: I. Atmospheric parameters and color similarity to the Sun