VizieR Online Data Catalog: Chromospheric emissions of 177 M dwarfs (Mignon+, 2024)

We studied the relation between three chromospheric indices from a large sample of M stars in detail; namely CaII H & K, Na D1 and D2, and Hα, first from their time-averaged values and then in more detail from the relationship between the corresponding time series.

We considered stars with at least ten nights of observations and a long enough temporal coverage to be able to implement a study of long-term variability as in Paper I (Mignon et al., 2023A&A...675A.168M, Cat. J/A+A/675/A168) (i.e. stars with a temporal coverage shorter than six times the rotation period are removed), which led to a sample of 177 stars, which are listed in Table A.1.

We analyse the correlations (defined as the Pearson coefficient), denoted C, between the time series for the three pairs of indices of our sample of 177 stars and compare them. The correlations are shown in Table A.2 for all stars.

(2 data files).