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Description
This table contains photometric and derived stellar parameters for a sample of 820 solar and late-type stars (the original table of 824 entries had 4 near-duplicate entries for the stars HD 19668, HD 95188, HD 216803 and HD 285382 which have been removed by the HEASARC) from nearby open clusters and the field, including rotation periods and X-ray luminosities. This sample was used by the authors to study the relationship between rotation and stellar activity and derive a new estimate of the convective turnover time. From an unbiased subset of this sample the power law slope of the unsaturated regime, L<sub>X</sub>/L<sub>bol</sub> ~ R<sub>o</sub><sup>beta</sup>, is fit as beta = -2.70 +/- 0.13. This is inconsistent with the canonical beta = -2 slope to a confidence of 5 sigma, and argues for an additional term in the dynamo number equation. From a simple scaling analysis, this implies Delta(Omega)/Omega ~ Omega<sup>0.7</sup>, i.e. the differential rotation of solar-type stars gradually declines as they spin down. Super-saturation is observed for the fastest rotators in this sample and its parametric dependencies are explored. Significant correlations are found with both the corotation radius and the excess polar updraft, the latter theory providing a stronger dependence and being supported by other observations. The authors estimate mass-dependent empirical thresholds for saturation and super- saturation and map out three regimes of coronal emission. Late F-type stars are shown never to pass through the saturated regime, passing straight from super-saturated to unsaturated X-ray emission. The theoretical threshold for coronal stripping is shown to be significantly different from the empirical saturation threshold (R<sub>o</sub> < 0.13), suggesting it is not responsible. Instead, the authors suggest that a different dynamo configuration is at work in stars with saturated coronal emission. This is supported by a correlation between the empirical saturation threshold and the time when stars transition between convective and interface sequences in rotational spin-down models. This table was created by the HEASARC in March 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/743/48">CDS Catalog J/ApJ/743/48</a> file catalog.dat. The original table had 824 entries, including 4 near-duplicate entries for the stars HD 19668, HD 95188, HD 216803 and HD 285382, which have been removed by the HEASARC. This is a service provided by NASA HEASARC .
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