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Solar analogues and Solar twins in the HARPS archive

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 نشر من قبل Juliet Datson
 تاريخ النشر 2014
  مجال البحث فيزياء
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We present 63 Solar analogues and twins for which high S/N archival data are available for the HARPS high resolution spectrograph at the ESO 3.6m telescope. We perform a differential analysis of these stellar spectra relative to the Solar spectrum, similar to previous work using ESO 2.2m/FEROS data, and expand our analysis by introducing a new method to test the temperature and metallicity calibration of Sun-like stars in the Geneva-Copenhagen-Survey (GCS). The HARPS data are significantly better than the FEROS data, with improvements in S/N, spectral resolution, and number of lines we can analyse. We confirm the offsets to the photometric scale found in our FEROS study. We confirm 3 Solar twins found in the FEROS data as Solar twins in the HARPS data, as well as identify 6 new twins.



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