DMPP-3/HD42936 Data files

<strong>HD42936_TERRA_RV.txt : </strong>contains the HARPS-TERRA reduced radial velocities for this system. The columns are Time (BJD-2450000), Radial Velocity, Error on RV, and dataset. TERRA uses a template matching process to extract radial velocities in a more accurate manner. For more information see<em> Anglada-Escudé G., Butler R. P., 2012, ApJS, 200, 15</em> <br> <strong>HD42936_DRS_BIS.txt, HD42936_DRS_FWHM.txt, HD42936_DRS_CCF_contrast.txt: </strong>these files contain the ancillary measurements from HARPS spectra, originating from the HARPS data reduction software (DRS). The full width half max (FWHM), bisector inverse slope (BIS) and contrast are measured from the cross-correlation function approach used in extracting radial velocities. These files have columns of: FWHM: Time (BJD); Value (km/s); error (km/s) BIS: Time (BJD-2400000); Value (m/s); error (m/s) Contrast: Time (BJD); Value (%, dimensionless); error (%, dimensionless) <br> <strong>HD42936_corrected_FWHM.txt: </strong>FWHM values after correction, where 4 outlying points have been removed in total, as well as removing a polynomial trend evident in HARPS pre fibre upgrade points, and a fibre upgrade related offset. For information on this trend, see <em>Costes J. C., et al., 2021, MNRAS, 505, 830.</em> The columns of this file are: Time (BJD); Median Subtracted FWHM value (km/s); FWHM error (km/s) <br> <strong>HD42936_CaHK_JB.txt, HD42936_Halpha_JB.txt, HD42936_NaD1_JB.txt, HD42936_NaD2_JB.txt, HD42936_NaD1D2_JB.txt: </strong>Activity time series values, reduced from publicly available HARPS spectra (ESO archive). We have extracted line strengths for Calcium II H and K, Hydrogen alpha, Sodium D lines 1, 2, and 1&amp;2 combined. These have been extracted using optimised, uniform (rectangular) line summing, with differing line core respective passband half widths. 0.3 [Angstroms] for Ca H, Na D1 &amp; D2. 0.25 [Angstroms] for Hydrogen alpha. 0.2 [Angstroms] for Ca K. For further information on the reduction process used, see <em>Barnes J. R., Haswell C. A., Staab D., Anglada-Escudé G., 2016, MNRAS,<br> 462, 1012.</em> The columns of these files are in the format of: Time (BJD-2400000); line strength value (dimensionless); Error on value (dimensionless). <br> <br> <br>